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Lipid BilayersLipidsDimyristoylphosphatidylcholineMembrane Fluidity1,2-DipalmitoylphosphatidylcholineLipid MetabolismMolecular ConformationLiposomesMembranes, ArtificialPhosphatidylcholinesPhospholipidsPhase TransitionLipid ABiophysicsPhosphatidylglycerolsAlamethicinBiophysical PhenomenaUnilamellar LiposomesGramicidinPhosphatidylethanolaminesIon ChannelsModels, ChemicalMicroscopy, Atomic ForceMagnetic Resonance SpectroscopyCalorimetry, Differential ScanningWaterModels, MolecularCholesterolCell MembraneElectric ConductivityThermodynamicsMembrane LipidsTemperatureMicellesMembrane MicrodomainsPermeabilityLipid PeroxidationHydrophobic and Hydrophilic InteractionsProtein Structure, SecondarySphingomyelinsSpectrometry, FluorescenceSurface PropertiesPhosphatidylserinesDiffusionTetraphenylborateMolecular Dynamics SimulationPorosityMembrane ProteinsPeptidesStatic ElectricityKineticsX-Ray DiffractionAmino Acid SequenceAntimicrobial Cationic PeptidesBatrachotoxinsAdsorptionMolecular Sequence DataMelittenModels, BiologicalSurface TensionElectrochemistryNuclear Magnetic Resonance, BiomolecularComputer SimulationMembrane FusionMembrane PotentialsDiphenylhexatrieneProtein ConformationMolecular StructureProtein BindingLipid PeroxidesSpectroscopy, Fourier Transform InfraredIon Channel GatingDeuteriumDetergentsGelsFluorescent DyesScattering, RadiationFluorescence PolarizationSpin LabelsCell Membrane PermeabilityCircular DichroismMagaininsStructure-Activity RelationshipHydrogen-Ion ConcentrationMathematicsRyanodine Receptor Calcium Release ChannelCationsIonsPorinsLauratesNanostructuresProtein Structure, TertiaryCalciumElectron Spin Resonance Spectroscopy2-NaphthylamineSilicon DioxideGalactolipidsFish VenomsOctoxynolSolutions
Lipid Bilayers
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
Lipids
A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)
Dimyristoylphosphatidylcholine
A synthetic phospholipid used in liposomes and lipid bilayers for the study of biological membranes.
Membrane Fluidity
The motion of phospholipid molecules within the lipid bilayer, dependent on the classes of phospholipids present, their fatty acid composition and degree of unsaturation of the acyl chains, the cholesterol concentration, and temperature.
1,2-Dipalmitoylphosphatidylcholine
Synthetic phospholipid used in liposomes and lipid bilayers to study biological membranes. It is also a major constituent of PULMONARY SURFACTANTS.
Lipid Metabolism
Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.
Molecular Conformation
The characteristic three-dimensional shape of a molecule.
Liposomes
Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.
Membranes, Artificial
Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.
Phosphatidylcholines
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.
Phospholipids
Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
Phase Transition
A change of a substance from one form or state to another.
Lipid A
Lipid A is the biologically active component of lipopolysaccharides. It shows strong endotoxic activity and exhibits immunogenic properties.
Biophysics
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
Phosphatidylglycerols
A nitrogen-free class of lipids present in animal and particularly plant tissues and composed of one mole of glycerol and 1 or 2 moles of phosphatidic acid. Members of this group differ from one another in the nature of the fatty acids released on hydrolysis.
Alamethicin
A cyclic nonadecapeptide antibiotic that can act as an ionophore and is produced by strains of Trichoderma viride. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Biophysical Phenomena
The physical characteristics and processes of biological systems.
Unilamellar Liposomes
Single membrane vesicles, generally made of PHOSPHOLIPIDS.
Gramicidin
A group of peptide antibiotics from BACILLUS brevis. Gramicidin C or S is a cyclic, ten-amino acid polypeptide and gramicidins A, B, D are linear. Gramicidin is one of the two principal components of TYROTHRICIN.
Phosphatidylethanolamines
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to an ethanolamine moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and ethanolamine and 2 moles of fatty acids.
Ion Channels
Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.
Models, Chemical
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
Microscopy, Atomic Force
A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.
Magnetic Resonance Spectroscopy
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
Calorimetry, Differential Scanning
Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.
Water
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Models, Molecular
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Cholesterol
The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.
Cell Membrane
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Electric Conductivity
The ability of a substrate to allow the passage of ELECTRONS.
Thermodynamics
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
Membrane Lipids
Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.
Temperature
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Micelles
Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.
Membrane Microdomains
Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.
Permeability
Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.
Lipid Peroxidation
Peroxidase catalyzed oxidation of lipids using hydrogen peroxide as an electron acceptor.
Hydrophobic and Hydrophilic Interactions
The thermodynamic interaction between a substance and WATER.
Protein Structure, Secondary
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
Sphingomyelins
A class of sphingolipids found largely in the brain and other nervous tissue. They contain phosphocholine or phosphoethanolamine as their polar head group so therefore are the only sphingolipids classified as PHOSPHOLIPIDS.
Spectrometry, Fluorescence
Measurement of the intensity and quality of fluorescence.
Surface Properties
Characteristics or attributes of the outer boundaries of objects, including molecules.
Phosphatidylserines
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a serine moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and serine and 2 moles of fatty acids.
Diffusion
The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.
Tetraphenylborate
An anionic compound that is used as a reagent for determination of potassium, ammonium, rubidium, and cesium ions. It also uncouples oxidative phosphorylation and forms complexes with biological materials, and is used in biological assays.
Molecular Dynamics Simulation
A computer simulation developed to study the motion of molecules over a period of time.
Porosity
Condition of having pores or open spaces. This often refers to bones, bone implants, or bone cements, but can refer to the porous state of any solid substance.
Membrane Proteins
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Peptides
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Static Electricity
The accumulation of an electric charge on a object
Kinetics
The rate dynamics in chemical or physical systems.
X-Ray Diffraction
The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Amino Acid Sequence
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Antimicrobial Cationic Peptides
Small cationic peptides that are an important component, in most species, of early innate and induced defenses against invading microbes. In animals they are found on mucosal surfaces, within phagocytic granules, and on the surface of the body. They are also found in insects and plants. Among others, this group includes the DEFENSINS, protegrins, tachyplesins, and thionins. They displace DIVALENT CATIONS from phosphate groups of MEMBRANE LIPIDS leading to disruption of the membrane.
Batrachotoxins
Batrachotoxin is the 20-alpha-bromobenzoate of batrachotoxin A; they are toxins from the venom of a small Colombian frog, Phyllobates aurotaenia, cause release of acetylcholine, destruction of synaptic vesicles and depolarization of nerve and muscle fibers.
Adsorption
The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Melitten
Basic polypeptide from the venom of the honey bee (Apis mellifera). It contains 26 amino acids, has cytolytic properties, causes contracture of muscle, releases histamine, and disrupts surface tension, probably due to lysis of cell and mitochondrial membranes.
Models, Biological
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Surface Tension
The force acting on the surface of a liquid, tending to minimize the area of the surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Electrochemistry
The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.
Nuclear Magnetic Resonance, Biomolecular
NMR spectroscopy on small- to medium-size biological macromolecules. This is often used for structural investigation of proteins and nucleic acids, and often involves more than one isotope.
Computer Simulation
Computer-based representation of physical systems and phenomena such as chemical processes.
Membrane Fusion
The adherence and merging of cell membranes, intracellular membranes, or artificial membranes to each other or to viruses, parasites, or interstitial particles through a variety of chemical and physical processes.
Membrane Potentials
The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).
Diphenylhexatriene
A fluorescent compound that emits light only in specific configurations in certain lipid media. It is used as a tool in the study of membrane lipids.
Protein Conformation
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Molecular Structure
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Protein Binding
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Lipid Peroxides
Peroxides produced in the presence of a free radical by the oxidation of unsaturated fatty acids in the cell in the presence of molecular oxygen. The formation of lipid peroxides results in the destruction of the original lipid leading to the loss of integrity of the membranes. They therefore cause a variety of toxic effects in vivo and their formation is considered a pathological process in biological systems. Their formation can be inhibited by antioxidants, such as vitamin E, structural separation or low oxygen tension.
Spectroscopy, Fourier Transform Infrared
A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.
Ion Channel Gating
The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.
Deuterium
Deuterium. The stable isotope of hydrogen. It has one neutron and one proton in the nucleus.
Detergents
Purifying or cleansing agents, usually salts of long-chain aliphatic bases or acids, that exert cleansing (oil-dissolving) and antimicrobial effects through a surface action that depends on possessing both hydrophilic and hydrophobic properties.
Gels
Colloids with a solid continuous phase and liquid as the dispersed phase; gels may be unstable when, due to temperature or other cause, the solid phase liquefies; the resulting colloid is called a sol.
Fluorescent Dyes
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
Scattering, Radiation
The diversion of RADIATION (thermal, electromagnetic, or nuclear) from its original path as a result of interactions or collisions with atoms, molecules, or larger particles in the atmosphere or other media. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Fluorescence Polarization
Measurement of the polarization of fluorescent light from solutions or microscopic specimens. It is used to provide information concerning molecular size, shape, and conformation, molecular anisotropy, electronic energy transfer, molecular interaction, including dye and coenzyme binding, and the antigen-antibody reaction.
Spin Labels
Molecules which contain an atom or a group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance spectroscopy and can be bonded to another molecule. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)
Cell Membrane Permeability
A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.
Circular Dichroism
A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Magainins
A class of antimicrobial peptides discovered in the skin of XENOPUS LAEVIS. They kill bacteria by permeabilizing cell membranes without exhibiting significant toxicity against mammalian cells.
Structure-Activity Relationship
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Hydrogen-Ion Concentration
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Mathematics
The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Ryanodine Receptor Calcium Release Channel
A tetrameric calcium release channel in the SARCOPLASMIC RETICULUM membrane of SMOOTH MUSCLE CELLS, acting oppositely to SARCOPLASMIC RETICULUM CALCIUM-TRANSPORTING ATPASES. It is important in skeletal and cardiac excitation-contraction coupling and studied by using RYANODINE. Abnormalities are implicated in CARDIAC ARRHYTHMIAS and MUSCULAR DISEASES.
Cations
Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.
Ions
An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.
Porins
Porins are protein molecules that were originally found in the outer membrane of GRAM-NEGATIVE BACTERIA and that form multi-meric channels for the passive DIFFUSION of WATER; IONS; or other small molecules. Porins are present in bacterial CELL WALLS, as well as in plant, fungal, mammalian and other vertebrate CELL MEMBRANES and MITOCHONDRIAL MEMBRANES.
Laurates
Salts and esters of the 12-carbon saturated monocarboxylic acid--lauric acid.
Nanostructures
Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.
Protein Structure, Tertiary
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
Calcium
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Electron Spin Resonance Spectroscopy
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
2-Naphthylamine
A naphthalene derivative with carcinogenic action.
Silicon Dioxide
Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.
Galactolipids
A group of GLYCOLIPIDS in which the sugar group is GALACTOSE. They are distinguished from GLYCOSPHINGOLIPIDS in lacking nitrogen. They constitute the majority of MEMBRANE LIPIDS in PLANTS.
Fish Venoms
Venoms produced by FISHES, including SHARKS and sting rays, usually delivered by spines. They contain various substances, including very labile toxins that affect the HEART specifically and all MUSCLES generally.
Octoxynol
Nonionic surfactant mixtures varying in the number of repeating ethoxy (oxy-1,2-ethanediyl) groups. They are used as detergents, emulsifiers, wetting agents, defoaming agents, etc. Octoxynol-9, the compound with 9 repeating ethoxy groups, is a spermatocide.
Solutions
The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Fatty Acids
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
4-Chloro-7-nitrobenzofurazan
A benzofuran derivative used as a protein reagent since the terminal N-NBD-protein conjugate possesses interesting fluorescence and spectral properties. It has also been used as a covalent inhibitor of both beef heart mitochondrial ATPase and bacterial ATPase.
Solvents
Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)
Microscopy, Fluorescence
Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.
Surface-Active Agents
Agents that modify interfacial tension of water; usually substances that have one lipophilic and one hydrophilic group in the molecule; includes soaps, detergents, emulsifiers, dispersing and wetting agents, and several groups of antiseptics.
Neutron Diffraction
The scattering of NEUTRONS by matter, especially crystals, with accompanying variation in intensity due to interference effects. It is useful in CRYSTALLOGRAPHY and POWDER DIFFRACTION.
Solubility
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Hydrogen Bonding
A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.
Chemistry, Physical
The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.
Protons
Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.
Macromolecular Substances
Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.
Silicon
A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].
Neutrons
Electrically neutral elementary particles found in all atomic nuclei except light hydrogen; the mass is equal to that of the proton and electron combined and they are unstable when isolated from the nucleus, undergoing beta decay. Slow, thermal, epithermal, and fast neutrons refer to the energy levels with which the neutrons are ejected from heavier nuclei during their decay.
Quaternary Ammonium Compounds
Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.
Nanotechnology
The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.
Aluminum Silicates
Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Anisotropy
A physical property showing different values in relation to the direction in or along which the measurement is made. The physical property may be with regard to thermal or electric conductivity or light refraction. In crystallography, it describes crystals whose index of refraction varies with the direction of the incident light. It is also called acolotropy and colotropy. The opposite of anisotropy is isotropy wherein the same values characterize the object when measured along axes in all directions.
Motion
Physical motion, i.e., a change in position of a body or subject as a result of an external force. It is distinguished from MOVEMENT, a process resulting from biological activity.
Egg Yolk
Cytoplasm stored in an egg that contains nutritional reserves for the developing embryo. It is rich in polysaccharides, lipids, and proteins.
Phosphorylcholine
Calcium and magnesium salts used therapeutically in hepatobiliary dysfunction.
Elasticity
Resistance and recovery from distortion of shape.
Calorimetry
The measurement of the quantity of heat involved in various processes, such as chemical reactions, changes of state, and formations of solutions, or in the determination of the heat capacities of substances. The fundamental unit of measurement is the joule or the calorie (4.184 joules). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Membranes
Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.
Escherichia coli
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Protein Multimerization
The assembly of the QUATERNARY PROTEIN STRUCTURE of multimeric proteins (MULTIPROTEIN COMPLEXES) from their composite PROTEIN SUBUNITS.
Polymers
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
Electric Capacitance
The ability of a substrate to retain an electrical charge.
Spectrophotometry, Infrared
Spectrophotometry in the infrared region, usually for the purpose of chemical analysis through measurement of absorption spectra associated with rotational and vibrational energy levels of molecules. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Time Factors
Elements of limited time intervals, contributing to particular results or situations.
Physicochemical Phenomena
The physical phenomena describing the structure and properties of atoms and molecules, and their reaction and interaction processes.
Sarcoplasmic Reticulum
A network of tubules and sacs in the cytoplasm of SKELETAL MUSCLE FIBERS that assist with muscle contraction and relaxation by releasing and storing calcium ions.
Calcium Channels
Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.
Cattle
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
Amphibian Proteins
Proteins obtained from species in the class of AMPHIBIANS.
Amantadine
An antiviral that is used in the prophylactic or symptomatic treatment of influenza A. It is also used as an antiparkinsonian agent, to treat extrapyramidal reactions, and for postherpetic neuralgia. The mechanisms of its effects in movement disorders are not well understood but probably reflect an increase in synthesis and release of dopamine, with perhaps some inhibition of dopamine uptake.
Glycolipids
Any compound containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety such as an acylglycerol (see GLYCERIDES), a sphingoid, a ceramide (CERAMIDES) (N-acylsphingoid) or a prenyl phosphate. (From IUPAC's webpage)
Ergosterol
A steroid of interest both because its biosynthesis in FUNGI is a target of ANTIFUNGAL AGENTS, notably AZOLES, and because when it is present in SKIN of animals, ULTRAVIOLET RAYS break a bond to result in ERGOCALCIFEROL.
Pressure
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Fluoresceins
A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays.
Dioxolanes
Transition Temperature
The temperature at which a substance changes from one state or conformation of matter to another.
Salts
Substances produced from the reaction between acids and bases; compounds consisting of a metal (positive) and nonmetal (negative) radical. (Grant & Hackh's Chemical Dictionary, 5th ed)
Polyethylene Glycols
Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.
Hemolysin Proteins
Proteins from BACTERIA and FUNGI that are soluble enough to be secreted to target ERYTHROCYTES and insert into the membrane to form beta-barrel pores. Biosynthesis may be regulated by HEMOLYSIN FACTORS.
Binding Sites
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Models, Theoretical
Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
G(M1) Ganglioside
A specific monosialoganglioside that accumulates abnormally within the nervous system due to a deficiency of GM1-b-galactosidase, resulting in GM1 gangliosidosis.
Myristates
Salts and esters of the 14-carbon saturated monocarboxylic acid--myristic acid.
Triglycerides
Micromanipulation
The performance of dissections, injections, surgery, etc., by the use of micromanipulators (attachments to a microscope) that manipulate tiny instruments.
Cardiolipins
Acidic phospholipids composed of two molecules of phosphatidic acid covalently linked to a molecule of glycerol. They occur primarily in mitochondrial inner membranes and in bacterial plasma membranes. They are the main antigenic components of the Wassermann-type antigen that is used in nontreponemal SYPHILIS SERODIAGNOSIS.
Microscopy, Electron
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
Recombinant Proteins
Proteins prepared by recombinant DNA technology.
Fatty Acids, Unsaturated
FATTY ACIDS in which the carbon chain contains one or more double or triple carbon-carbon bonds.
Hemolysis
The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.
Quartz
Quartz (SiO2). A glassy or crystalline form of silicon dioxide. Many colored varieties are semiprecious stones. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Fluorescence Resonance Energy Transfer
A type of FLUORESCENCE SPECTROSCOPY using two FLUORESCENT DYES with overlapping emission and absorption spectra, which is used to indicate proximity of labeled molecules. This technique is useful for studying interactions of molecules and PROTEIN FOLDING.
Alkanes
The generic name for the group of aliphatic hydrocarbons Cn-H2n+2. They are denoted by the suffix -ane. (Grant & Hackh's Chemical Dictionary, 5th ed)
Ceramides
Members of the class of neutral glycosphingolipids. They are the basic units of SPHINGOLIPIDS. They are sphingoids attached via their amino groups to a long chain fatty acyl group. They abnormally accumulate in FABRY DISEASE.
Peptide Fragments
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
Monte Carlo Method
In statistics, a technique for numerically approximating the solution of a mathematical problem by studying the distribution of some random variable, often generated by a computer. The name alludes to the randomness characteristic of the games of chance played at the gambling casinos in Monte Carlo. (From Random House Unabridged Dictionary, 2d ed, 1993)
Tryptophan
An essential amino acid that is necessary for normal growth in infants and for NITROGEN balance in adults. It is a precursor of INDOLE ALKALOIDS in plants. It is a precursor of SEROTONIN (hence its use as an antidepressant and sleep aid). It can be a precursor to NIACIN, albeit inefficiently, in mammals.
Phospholipid Ethers
Phospholipids which have an alcohol moiety in ethereal linkage with a saturated or unsaturated aliphatic alcohol. They are usually derivatives of phosphoglycerols or phosphatidates. The other two alcohol groups of the glycerol backbone are usually in ester linkage. These compounds are widely distributed in animal tissues.
Glycerophospholipids
Derivatives of phosphatidic acid in which the hydrophobic regions are composed of two fatty acids and a polar alcohol is joined to the C-3 position of glycerol through a phosphodiester bond. They are named according to their polar head groups, such as phosphatidylcholine and phosphatidylethanolamine.
Phosphorus Isotopes
Stable phosphorus atoms that have the same atomic number as the element phosphorus, but differ in atomic weight. P-31 is a stable phosphorus isotope.
Rabbits
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Bacterial Outer Membrane Proteins
Proteins isolated from the outer membrane of Gram-negative bacteria.
Erythrocyte Membrane
The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.
Crystallization
The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Fluorescence
The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.
Energy Transfer
The transfer of energy of a given form among different scales of motion. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed). It includes the transfer of kinetic energy and the transfer of chemical energy. The transfer of chemical energy from one molecule to another depends on proximity of molecules so it is often used as in techniques to measure distance such as the use of FORSTER RESONANCE ENERGY TRANSFER.
Proteolipids
Protein-lipid combinations abundant in brain tissue, but also present in a wide variety of animal and plant tissues. In contrast to lipoproteins, they are insoluble in water, but soluble in a chloroform-methanol mixture. The protein moiety has a high content of hydrophobic amino acids. The associated lipids consist of a mixture of GLYCEROPHOSPHATES; CEREBROSIDES; and SULFOGLYCOSPHINGOLIPIDS; while lipoproteins contain PHOSPHOLIPIDS; CHOLESTEROL; and TRIGLYCERIDES.
Fatty Acids, Monounsaturated
Fatty acids which are unsaturated in only one position.
Pulmonary Surfactants
Substances and drugs that lower the SURFACE TENSION of the mucoid layer lining the PULMONARY ALVEOLI.
Biological Transport
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
Intracellular Membranes
Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
Sodium Channels
Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.
Fluorescence Recovery After Photobleaching
A method used to study the lateral movement of MEMBRANE PROTEINS and LIPIDS. A small area of a cell membrane is bleached by laser light and the amount of time necessary for unbleached fluorescent marker-tagged proteins to diffuse back into the bleached site is a measurement of the cell membrane's fluidity. The diffusion coefficient of a protein or lipid in the membrane can be calculated from the data. (From Segen, Current Med Talk, 1995).
Anions
Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.
Freeze Fracturing
Preparation for electron microscopy of minute replicas of exposed surfaces of the cell which have been ruptured in the frozen state. The specimen is frozen, then cleaved under high vacuum at the same temperature. The exposed surface is shadowed with carbon and platinum and coated with carbon to obtain a carbon replica.

Three-dimensional structure of a recombinant gap junction membrane channel. (1/7162)

Gap junction membrane channels mediate electrical and metabolic coupling between adjacent cells. The structure of a recombinant cardiac gap junction channel was determined by electron crystallography at resolutions of 7.5 angstroms in the membrane plane and 21 angstroms in the vertical direction. The dodecameric channel was formed by the end-to-end docking of two hexamers, each of which displayed 24 rods of density in the membrane interior, which is consistent with an alpha-helical conformation for the four transmembrane domains of each connexin subunit. The transmembrane alpha-helical rods contrasted with the double-layered appearance of the extracellular domains. Although not indicative for a particular type of secondary structure, the protein density that formed the extracellular vestibule provided a tight seal to exclude the exchange of substances with the extracellular milieu.  (+info)

Gating connexin 43 channels reconstituted in lipid vesicles by mitogen-activated protein kinase phosphorylation. (2/7162)

The regulation of gap junctional permeability by phosphorylation was examined in a model system in which connexin 43 (Cx43) gap junction hemichannels were reconstituted in lipid vesicles. Cx43 was immunoaffinity-purified from rat brain, and Cx43 channels were reconstituted into unilamellar phospholipid liposomes. The activities of the reconstituted channels were measured by monitoring liposome permeability. Liposomes containing the Cx43 protein were fractionated on the basis of permeability to sucrose using sedimentation in an iso-osmolar density gradient. The gradient allowed separation of the sucrose-permeable and -impermeable liposomes. Liposomes that were permeable to sucrose were also permeable to the communicating dye molecule lucifer yellow. Permeability, and therefore activity of the reconstituted Cx43 channels, were directly dependent on the state of Cx43 phosphorylation. The permeability of liposomes containing Cx43 channels was increased by treatment of liposomes with calf intestinal phosphatase. Moreover, liposomes formed with Cx43 that had been dephosphorylated by calf intestinal phosphatase treatment showed increased permeability to sucrose. The role of phosphorylation in the gating mechanism of Cx43 channels was supported further by the observation that phosphorylation of Cx43 by mitogen-activated protein kinase reversibly reduced the permeability of liposomes containing dephosphorylated Cx43. Our results show a direct correlation between gap junctional permeability and the phosphorylation state of Cx43.  (+info)

Calculation of a Gap restoration in the membrane skeleton of the red blood cell: possible role for myosin II in local repair. (3/7162)

Human red blood cells contain all of the elements involved in the formation of nonmuscle actomyosin II complexes (V. M. Fowler. 1986. J. Cell. Biochem. 31:1-9; 1996. Curr. Opin. Cell Biol. 8:86-96). No clear function has yet been attributed to these complexes. Using a mathematical model for the structure of the red blood cell spectrin skeleton (M. J. Saxton. 1992. J. Theor. Biol. 155:517-536), we have explored a possible role for myosin II bipolar minifilaments in the restoration of the membrane skeleton, which may be locally damaged by major mechanical or chemical stress. We propose that the establishment of stable links between distant antiparallel actin protofilaments after a local myosin II activation may initiate the repair of the disrupted area. We show that it is possible to define conditions in which the calculated number of myosin II minifilaments bound to actin protofilaments is consistent with the estimated number of myosin II minifilaments present in the red blood cells. A clear restoration effect can be observed when more than 50% of the spectrin polymers of a defined area are disrupted. It corresponds to a significant increase in the spectrin density in the protein free region of the membrane. This may be involved in a more complex repair process of the red blood cell membrane, which includes the vesiculation of the bilayer and the compaction of the disassembled spectrin network.  (+info)

Solid-state NMR and hydrogen-deuterium exchange in a bilayer-solubilized peptide: structural and mechanistic implications. (4/7162)

Hydrogen-deuterium exchange has been monitored by solid-state NMR to investigate the structure of gramicidin M in a lipid bilayer and to investigate the mechanisms for polypeptide insertion into a lipid bilayer. Through exchange it is possible to observe 15N-2H dipolar interactions in oriented samples that yield precise structural constraints. In separate experiments the pulse sequence SFAM was used to measure dipolar distances in this structure, showing that the dimer is antiparallel. The combined use of orientational and distance constraints is shown to be a powerful structural approach. By monitoring the hydrogen-deuterium exchange at different stages in the insertion of peptides into a bilayer environment it is shown that dimeric gramicidin is inserted into the bilayer intact, i.e., without separating into monomer units. The exchange mechanism is investigated for various sites and support for a relayed imidic acid mechanism is presented. Both acid and base catalyzed mechanisms may be operable. The nonexchangeable sites clearly define a central core to which water is inaccessible or hydroxide or hydronium ion is not even momentarily stable. This provides strong evidence that this is a nonconducting state.  (+info)

Molecular dynamics study of substance P peptides in a biphasic membrane mimic. (5/7162)

Two neuropeptides, substance P (SP) and SP-tyrosine-8 (SP-Y8), have been studied by molecular dynamics (MD) simulation in a TIP3P water/CCl4 biphasic solvent system as a mimic for the water-membrane system. Initially, distance restraints derived from NMR nuclear Overhauser enhancements (NOE) were incorporated in the restrained MD (RMD) in the equilibration stage of the simulation. The starting orientation/position of the peptides for the MD simulation was either parallel to the water/CCl4 interface or in a perpendicular/insertion mode. In both cases the peptides equilibrated and adopted a near-parallel orientation within approximately 250 ps. After equilibration, the conformation and orientation of the peptides, the solvation of both the backbone and the side chain of the residues, hydrogen bonding, and the dynamics of the peptides were analyzed from trajectories obtained in the RMD or the subsequent free MD (where the NOE restraints were removed). These analyses showed that the peptide backbone of nearly all residues are either solvated by water or are hydrogen-bonded. This is seen to be an important factor against the insertion mode of interaction. Most of the interactions with the hydrophobic phase come from the hydrophobic interactions of the side chains of Pro-4, Phe-7, Phe-8, Leu-10, and Met-11 for SP, and Phe-7, Leu-10, Met-11 and, to a lesser extent, Tyr-8 in SP-Y8. Concerted conformational transitions took place in the time frame of hundreds of picoseconds. The concertedness of the transition was due to the tendency of the peptide to maintain the necessary secondary structure to position the peptide properly with respect to the water/CCl4 interface.  (+info)

Molecular dynamics study of substance P peptides partitioned in a sodium dodecylsulfate micelle. (6/7162)

Two neuropeptides, substance P (SP) and SP-tyrosine-8 (SP-Y8), have been studied by molecular dynamics (MD) simulation in an explicit sodium dodecylsulfate (SDS) micelle. Initially, distance restraints derived from NMR nuclear Overhauser enhancements (NOE) were incorporated in the restrained MD (RMD) during the equilibration stage of the simulation. It was shown that when SP-Y8 was initially placed in an insertion (perpendicular) configuration, the peptide equilibrated to a surface-bound (parallel) configuration in approximately 450 ps. After equilibration, the conformation and orientation of the peptides, the solvation of both the backbone and the side chain of the residues, hydrogen bonding, and the dynamics of the peptides were analyzed from trajectories obtained from the RMD or the subsequent free MD (where the NOE restraints were removed). These analyses showed that the peptide backbones of all residues are either solvated by water or are hydrogen-bonded. This is seen to be an important factor against the insertion mode of interaction. Most of the interactions come from the hydrophobic interaction between the side chains of Lys-3, Pro-4, Phe-7, Phe-8, Leu-10, and Met-11 for SP, from Lys-3, Phe-7, Leu-10, and Met-11 in SP-Y8, and the micellar interior. Significant interactions, electrostatic and hydrogen bonding, between the N-terminal residues, Arg-Pro-Lys, and the micellar headgroups were observed. These latter interactions served to affect both the structure and, especially, the flexibility, of the N-terminus. The results from simulation of the same peptides in a water/CCl4 biphasic cell were compared with the results of the present study, and the validity of using the biphasic system as an approximation for peptide-micelle or peptide-bilayer systems is discussed.  (+info)

Charge pairing of headgroups in phosphatidylcholine membranes: A molecular dynamics simulation study. (7/7162)

Molecular dynamics simulation of the hydrated dimyristoylphosphatidylcholine (DMPC) bilayer membrane in the liquid-crystalline phase was carried out for 5 ns to study the interaction among DMPC headgroups in the membrane/water interface region. The phosphatidylcholine headgroup contains a positively charged choline group and negatively charged phosphate and carbonyl groups, although it is a neutral molecule as a whole. Our previous study (Pasenkiewicz-Gierula, M., Y. Takaoka, H. Miyagawa, K. Kitamura, and A. Kusumi. 1997. J. Phys. Chem. 101:3677-3691) showed the formation of water cross-bridges between negatively charged groups in which a water molecule is simultaneously hydrogen bonded to two DMPC molecules. Water bridges link 76% of DMPC molecules in the membrane. In the present study we show that relatively stable charge associations (charge pairs) are formed between the positively and negatively charged groups of two DMPC molecules. Charge pairs link 93% of DMPC molecules in the membrane. Water bridges and charge pairs together form an extended network of interactions among DMPC headgroups linking 98% of all membrane phospholipids. The average lifetimes of DMPC-DMPC associations via charge pairs, water bridges and both, are at least 730, 1400, and over 1500 ps, respectively. However, these associations are dynamic states and they break and re-form several times during their lifetime.  (+info)

Kinetic and thermodynamic aspects of lipid translocation in biological membranes. (8/7162)

A theoretical analysis of the lipid translocation in cellular bilayer membranes is presented. We focus on an integrative model of active and passive transport processes determining the asymmetrical distribution of the major lipid components between the monolayers. The active translocation of the aminophospholipids phosphatidylserine and phosphatidylethanolamine is mathematically described by kinetic equations resulting from a realistic ATP-dependent transport mechanism. Concerning the passive transport of the aminophospholipids as well as of phosphatidylcholine, sphingomyelin, and cholesterol, two different approaches are used. The first treatment makes use of thermodynamic flux-force relationships. Relevant forces are transversal concentration differences of the lipids as well as differences in the mechanical states of the monolayers due to lateral compressions. Both forces, originating primarily from the operation of an aminophospholipid translocase, are expressed as functions of the lipid compositions of the two monolayers. In the case of mechanical forces, lipid-specific parameters such as different molecular surface areas and compression force constants are taken into account. Using invariance principles, it is shown how the phenomenological coefficients depend on the total lipid amounts. In a second approach, passive transport is analyzed in terms of kinetic mechanisms of carrier-mediated translocation, where mechanical effects are incorporated into the translocation rate constants. The thermodynamic as well as the kinetic approach are applied to simulate the time-dependent redistribution of the lipid components in human red blood cells. In the thermodynamic model the steady-state asymmetrical lipid distribution of erythrocyte membranes is simulated well under certain parameter restrictions: 1) the time scales of uncoupled passive transbilayer movement must be different among the lipid species; 2) positive cross-couplings of the passive lipid fluxes are needed, which, however, may be chosen lipid-unspecifically. A comparison of the thermodynamic and the kinetic approaches reveals that antiport mechanisms for passive lipid movements may be excluded. Simulations with kinetic symport mechanisms are in qualitative agreement with experimental data but show discrepancies in the asymmetrical distribution for sphingomyelin.  (+info)

Fluorescence modulation sensing of positively and negatively charged proteins on lipid bilayers<...
TY - JOUR. T1 - Fluorescence modulation sensing of positively and negatively charged proteins on lipid bilayers. AU - Robison, Aaron D.. AU - Huang, Da. AU - Jung, Hyunsook. AU - Cremer, Paul S.. PY - 2013/1/1. Y1 - 2013/1/1. N2 - Background: Detecting ligand-receptor binding on cell membrane surfaces is required to understand their function and behavior. Detection platforms can also provide an avenue for the development of medical devices and sensor biotechnology. The use of fluorescence techniques for such purposes is highly desirable as they provide high sensitivity. Herein, we describe a technique that utilizes the sensitivity of fluorescence without directly tagging the analyte of interest to monitor ligand-receptor interactions on supported lipid bilayers. The fluorescence signal is modulated according to the charge state of the target analyte. The binding event elicits protonation or deprotonation of pH-responsive reporter dyes embedded in the lipid bilayer. Methods: Supported lipid ...
https://pennstate.pure.elsevier.com/en/publications/fluorescence-modulation-sensing-of-positively-and-negatively-char
Lipid Flip-Flop and Pore Nucleation on Zwitterionic Bilayers are Asymmetric under Ionic Imbalance | MIT Department of Materials...Lipid Flip-Flop and Pore Nucleation on Zwitterionic Bilayers are Asymmetric under Ionic Imbalance | MIT Department of Materials...
Lipid flip-flop and its associated transient pore formation are key thermodynamic properties of living cell membranes. However, there is a lack of understanding of whether ionic imbalance that exists ubiquitously across cell membranes affects lipid flip-flop and its associated functions. Potential of mean force calculations show that the free-energy barrier of lipid flip-flop on the extracellular leaflet reduces with the presence of ionic imbalance, whereas the barrier on the intracellular leaflet is generally not affected. The linear decrease of the activation energy of lipid flip-flop on the extracellular leaflet is consistent with the experimentally measured conductance-voltage relationship of zwitterionic lipid bilayers. This suggests: 1) lipid flip-flop has a directionality under physiological conditions and phospholipids accumulate at a rate on the order of 105 mu m(-2) h(-1) on the cytoplasmic side of cell membranes; 2) ion permeation across a lipid membrane is moderated by lipid ...
http://dmse.mit.edu/publications/lipid-flip-flop-and-pore-nucleation-zwitterionic-bilayers-are-asymmetric-under-ionic
197b) Simulations of the Bilayer-Mediated Assembly of Cationic Nanoparticles on Phase-Separated Lipid Bilayers | AIChE Academy197b) Simulations of the Bilayer-Mediated Assembly of Cationic Nanoparticles on Phase-Separated Lipid Bilayers | AIChE Academy
Understanding interactions between functionalized gold nanoparticles (NPs) and lipid bilayers is essential for their use in biomedical applications. Experiments and continuum-scale simulations have suggested that small (~5 nm diameter) cationic NPs aggregate when adsorbed to the surface of zwitterionic lipid bilayers despite being stable in aqueous solution, suggesting that bilayer-mediated interactions facilitate assembly. Determining the origin of these effects and the impact of other bilayer features, such as lipid phase separation, on the interfacial assembly of NPs would enable the design of NPs for applications that require NP assembly, such as photothermal therapy.. In this work, we use chemically specific coarse-grained molecular dynamics simulations to show that cationic NP adsorption to lipid bilayers is driven by a balance between favorable NP-lipid interactions and the unfavorable mechanical deformation of the bilayer to create local curvature. The minimization of induced curvature ...
https://www.aiche.org/academy/conferences/aiche-annual-meeting/2020/proceeding/paper/197b-simulations-bilayer-mediated-assembly-cationic-nanoparticles-on-phase-separated-lipid-bilayers
Antimicrobial defensin peptides form voltage-dependent ion-permeable channels in planar lipid bilayer membranes | PNASAntimicrobial defensin peptides form voltage-dependent ion-permeable channels in planar lipid bilayer membranes | PNAS
Defensins are cationic, cysteine-rich peptides (Mr = 3500-4000) found in the cytoplasmic granules of neutrophils and macrophages. These peptides possess broad antimicrobial activity in vitro against bacteria, fungi, tumor cells, and enveloped viruses, and they are believed to contribute to the oxygen-independent antimicrobial defenses of neutrophils and macrophages. Pathophysiologic studies in vitro have pointed to the plasma membrane as a possible target for the cytotoxic action of defensins. We report here that defensins form voltage-dependent, weakly anion-selective channels in planar lipid bilayer membranes, and we suggest that this channel-forming ability contributes to their antimicrobial properties observed in vitro.. ...
https://www.pnas.org/content/87/1/210?ijkey=f7fe6230948c512efbc9f1dc58ef462cda286792&keytype2=tf_ipsecsha
Motility and ultrastructure of large granular lymphocytes on lipid bilayers reconstituted with adhesion receptors LFA-1, ICAM-1...
Large granular lymphocytes, mediators of NK activity, bind to other cells using both the LFA (lymphocyte function-associated)-1-ICAM and the CD2-LFA-3 adhesion pathways. Here we have studied the motility and ultrastructure of large granule lymphocyte (LGL) on lipid bilayers containing purified LFA-1, ICAM-1, and the transmembrane and glycophosphatidylinositol isoforms of LFA-3. LGLs moved at 8 microns/min on ICAM-1 but poorly (less than 1 microns/min) on its receptor pair LFA-1. TM-LFA-3 promoted locomotion at a rate close to ICAM-1, whereas the cells were less motile on GPI-LFA-3. The difference in the rates of locomotion on the two isoforms of LFA-3 is presumably attributable to their difference in anchoring and lateral mobility in the bilayer. In spite of the variation in motility the ultrastructure of the adhering cells was similar on all four ligands. LGLs contacted the membrane variably, i.e., cells adhering only in a few small areas or in larger areas were detected on each ligand. The relative
https://www.ndorms.ox.ac.uk/publications/482699
Motility and ultrastructure of large granular lymphocytes on lipid bilayers reconstituted with adhesion receptors LFA-1, ICAM-1...Motility and ultrastructure of large granular lymphocytes on lipid bilayers reconstituted with adhesion receptors LFA-1, ICAM-1...
Large granular lymphocytes, mediators of NK activity, bind to other cells using both the LFA (lymphocyte function-associated)-1-ICAM and the CD2-LFA-3 adhesion pathways. Here we have studied the motility and ultrastructure of large granule lymphocyte (LGL) on lipid bilayers containing purified LFA-1, ICAM-1, and the transmembrane and glycophosphatidylinositol isoforms of LFA-3. LGLs moved at 8 microns/min on ICAM-1 but poorly (less than 1 microns/min) on its receptor pair LFA-1. TM-LFA-3 promoted locomotion at a rate close to ICAM-1, whereas the cells were less motile on GPI-LFA-3. The difference in the rates of locomotion on the two isoforms of LFA-3 is presumably attributable to their difference in anchoring and lateral mobility in the bilayer. In spite of the variation in motility the ultrastructure of the adhering cells was similar on all four ligands. LGLs contacted the membrane variably, i.e., cells adhering only in a few small areas or in larger areas were detected on each ligand. The ...
http://jcb.rupress.org/content/115/3/861
Hydrodynamic interaction between overlapping domains during recurrence of registration within planar lipid bilayer membranes<...Hydrodynamic interaction between overlapping domains during recurrence of registration within planar lipid bilayer membranes<...
TY - JOUR. T1 - Hydrodynamic interaction between overlapping domains during recurrence of registration within planar lipid bilayer membranes. AU - Han, Tao. AU - Bailey, Trevor P.. AU - Haataja, Mikko. PY - 2014/3/26. Y1 - 2014/3/26. N2 - Due to a thermodynamic coupling between the two leaflets comprising a lipid bilayer, compositional lipid domains residing within opposing leaflets are often found in registry. If the system is perturbed by displacing one domain relative to the other, diffusive and advective lipid fluxes are established to restore equilibrium and reestablish domain overlap. In this work, we focus on the advective part of the process, and first derive an analytical expression for the hydrodynamic drag coefficient associated with the advective flow for the special case of perfect domain overlap. The resulting expression identifies parameter regions where sliding friction between the leaflets dominates over viscous dissipation within the leaflets or vice versa. It is shown that in ...
https://collaborate.princeton.edu/en/publications/hydrodynamic-interaction-between-overlapping-domains-during-recur
Atomistic molecular dynamics simulations of propofol and fentanyl in phosphatidylcholine lipid bilayers - data - Faulkner C,...Atomistic molecular dynamics simulations of propofol and fentanyl in phosphatidylcholine lipid bilayers - data - Faulkner C,...
The data here provides the raw data for the calculations of radial distribution functions, hydrogen bond analysis, lateral lipid diffusion and lipid tail order parameters. This raw data was generated using tools from the CPPTRAJ analysis package which is freely available with the AmberTools program (https://ambermd.org/AmberTools.php). The data presented here shows how two drug molecules (propofol and fentanyl) alter the physical and mechanical properties of DOPC and DPPC lipid bilayers, and for the first time, how a general anesthetic and an opioid analgesic/anesthetic differ in their interactions with phospholipid membranes, by direct comparison. Understanding the differences between opioid and anesthetic interactions with phospholipid bilayers will lead to a more complete understanding of general anesthesia at the molecular level ...
https://research.cardiff.ac.uk/converis/portal/detail/Dataset/92362446?auxfun=&lang=en_GB
Molecular Dynamics Investigations of Structure and Dynamics of Lipid Bilayers and Associated AnestheticsMolecular Dynamics Investigations of Structure and Dynamics of Lipid Bilayers and Associated Anesthetics
Detailed understanding of lipid bilayers are of tremendous importance due to their role in many biological processes. This Thesis focuses on structural and dynamical properties of lipid bilayers and their interactions with locally acting anesthetics, studied by Molecular Dynamics simulations.. The effect of dehydration of a lipid bilayer is a biologically important phenomenon which was investigated by detailed examination of a number of structural and dynamical lipid parameters at different levels of hydration. The result shows that whereas the structural properties of the bilayer only moderately depend on the degree of hydration, the dynamics of the system is affected very strongly.. Related to changes in the bilayer caused by hydration are structural and dynamical changes caused by the presence of anesthetics. Lidocaine is a common, locally acting anesthetic that interacts with lipid bilayers. The difference in position, orientation and diffusional behavior for charged and uncharged lidocaine ...
http://su.diva-portal.org/smash/record.jsf?pid=diva2:197562
Journal Club Theme of February 2007: Computational Mechanics of Biomembranes | iMechanica
Lipid bilayers constitute one of the critical parts of all biological membranes, including cell membranes. A nice description of lipid bilayers and their function in biological membranes can be found here. They can be exceptionally complex and contain hundreds of different constituents, so simpler model lipid bilayers are often produced in the laboratory and studied experimentally. They form closed spheroidal structures, called liposomes, with a thickness of a few nm, and characteristic linear dimensions up to several microns. Larger such structures are usually called Giant Unilamellar Vesicles, or GUVs. Why should we care about these structures as mechanicians? For a number of reasons, the elastic properties of lipid membranes are thought to play a crucial role in governing their potential configurations. Recent experimental studies of the role of membrane curvature on domain formation in biomembranes, for example, provide testament to this notion. Images of their work are reproduced (with ...
https://imechanica.org/comment/1106
Journal Club Theme of February 2007: Computational Mechanics of Biomembranes | iMechanica
Lipid bilayers constitute one of the critical parts of all biological membranes, including cell membranes. A nice description of lipid bilayers and their function in biological membranes can be found here. They can be exceptionally complex and contain hundreds of different constituents, so simpler model lipid bilayers are often produced in the laboratory and studied experimentally. They form closed spheroidal structures, called liposomes, with a thickness of a few nm, and characteristic linear dimensions up to several microns. Larger such structures are usually called Giant Unilamellar Vesicles, or GUVs. Why should we care about these structures as mechanicians? For a number of reasons, the elastic properties of lipid membranes are thought to play a crucial role in governing their potential configurations. Recent experimental studies of the role of membrane curvature on domain formation in biomembranes, for example, provide testament to this notion. Images of their work are reproduced (with ...
https://imechanica.org/comment/1169
Molecules | Free Full-Text | Alcohol Interactions with Lipid BilayersMolecules | Free Full-Text | Alcohol Interactions with Lipid Bilayers
We investigate the structural changes to lipid membrane that ensue from the addition of aliphatic alcohols with various alkyl tail lengths. Small angle neutron diffraction from flat lipid bilayers that are hydrated through water vapor has been employed to eliminate possible artefacts of the membrane curvature and the alcohols membrane-water partitioning. We have observed clear changes to membrane structure in both transversal and lateral directions. Most importantly, our results suggest the alteration of the membrane-water interface. The water encroachment has shifted in the way that alcohol loaded bilayers absorbed more water molecules when compared to the neat lipid bilayers. The experimental results have been corroborated by molecular dynamics simulations to reveal further details. Namely, the order parameter profiles have been fruitful in correlating the mechanical model of structural changes to the effect of anesthesia.
http://www.mdpi.com/1420-3049/22/12/2078/xml
Solid-Like Domains in Mixed Lipid Bilayers: Effect of Membrane Lamellarity and Transition PathwaySolid-Like Domains in Mixed Lipid Bilayers: Effect of Membrane Lamellarity and Transition Pathway
We present optical observations of phase separation in mixed model membranes in the form of giant unilamellar vesicles. These observations are compared to the phase behavior of lipid mixtures, which we determined by X-ray scattering and differential scanning calorimetry or extracted from the existing literature. The domain properties are affected not only by the bulk phase behavior but also by the membrane lamellarity and phase transition pathways. These observations have important implications for how phase behavior determined by bulk methods using dense, multilamellar lipid bilayers are linked to phase separation in giant, unilamellar lipid bilayers as observed by microscopy ...
https://repositories.lib.utexas.edu/handle/2152/39120
Fluorescence modulation sensing of positively and negatively charged proteins on lipid bilayers | Biointerphases | Full TextFluorescence modulation sensing of positively and negatively charged proteins on lipid bilayers | Biointerphases | Full Text
Detecting ligand-receptor binding on cell membrane surfaces is required to understand their function and behavior. Detection platforms can also provide an avenue for the development of medical devices and sensor biotechnology. The use of fluorescence techniques for such purposes is highly desirable as they provide high sensitivity. Herein, we describe a technique that utilizes the sensitivity of fluorescence without directly tagging the analyte of interest to monitor ligand-receptor interactions on supported lipid bilayers. The fluorescence signal is modulated according to the charge state of the target analyte. The binding event elicits protonation or deprotonation of pH-responsive reporter dyes embedded in the lipid bilayer. Supported lipid membranes containing ortho-conjugated rhodamine B-POPE (1-hexadecanoyl-2-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine), which fluoresces in its protonated but not in its deprotonated form, were utilized as sensor platforms for biotin-avidin and biotin
https://biointerphases.springeropen.com/articles/10.1186/1559-4106-8-1
The measurement of cardiac membrane channels following their incorporation into planar phospholipid bilayers -ORCAThe measurement of cardiac membrane channels following their incorporation into planar phospholipid bilayers -ORCA
Williams, Alan John 1984. The measurement of cardiac membrane channels following their incorporation into planar phospholipid bilayers. In: Harris, P.C. ed ...
http://orca.cf.ac.uk/29029/
NIOSHTIC-2 Publications Search - 00092786 - Toxicity of Halogenated Compounds on Lipid Bilayers: Report on Project VKC-C23-169.NIOSHTIC-2 Publications Search - 00092786 - Toxicity of Halogenated Compounds on Lipid Bilayers: Report on Project VKC-C23-169.
The perturbation of model lipid bilayer vesicles by halogenated hydrocarbons was investigated to determine if cellular membrane damage could be evaluated and used as a screening technique for toxicity. A fluorescent probe of 1-anilino-8-naphthalene-sulfonate (82768) (ANS) was bound to synthetic phospholipid vesicles prepared from egg lecithin and dimyristoyl-phosphatidyl-choline (DML). The fluores
https://www.cdc.gov/niosh/nioshtic-2/00092786.html
Ca(2+)-activated K+ channels from an insulin-secreting cell line incorporated into planar lipid bilayers. - Oxford Neuroscience
This study evaluates the use of the planar lipid bilayer as a functional assay of Ca(2+)-activated K+ channel activity for use in purification of the channel protein. Ca(2+)-activated K+ channels from the plasma membrane of an insulin-secreting hamster Beta-cell line (HIT T15) were incorporated into planar lipid bilayers. The single channel conductance was 233 picoSiemens (pS) in symmetrical 140 mmol/l KCl and the channel was strongly K(+)-selective (PCl/PK = 0.046; PNa/PK = 0.027). Channels incorporated into the bilayer with two orientations. In 65% of cases, the probability of the channel being open was increased by raising calcium on the cis side of the bilayer (to which the membrane vesicles were added) or by making the cis side potential more positive. At a membrane potential of + 20 mV, which is close to the peak of the Beta-cell action potential, channel activity was half-maximal at a Ca2+ concentration of about 15 mumol/l. Charybdotoxin greatly reduced the probability of the channel being open
https://www.neuroscience.ox.ac.uk/publications/113455
Pentelute Lab MIT | Cholesterol-binding site of the influenza M2 protein in lipid bilayers from solid-state NMRPentelute Lab MIT | Cholesterol-binding site of the influenza M2 protein in lipid bilayers from solid-state NMR
The influenza M2 protein not only forms a proton channel but also mediates membrane scission in a cholesterol-dependent manner to cause virus budding and release. The atomic interaction of cholesterol with M2, as with most eukaryotic membrane proteins, has long been elusive. We have now determined the cholesterol-binding site of the M2 protein in phospholipid bilayers using solid-state NMR spectroscopy. Chain-fluorinated cholesterol was used to measure cholesterol proximity to M2 while sterol-deuterated cholesterol was used to measure bound-cholesterol orientation in lipid bilayers. Carbon-fluorine distance measurements show that at a cholesterol concentration of 17 mol%, two cholesterol molecules bind each M2 tetramer. Cholesterol binds the C-terminal transmembrane (TM) residues, near an amphipathic helix, without requiring a cholesterol recognition sequence motif. Deuterium NMR spectra indicate that bound cholesterol is approximately parallel to the bilayer normal, with the rough face of the sterol
http://www.pentelutelabmit.com/portfolio_page/cholesterol-binding-site-of-the-influenza-m2-protein-in-lipid-bilayers-from-solid-state-nmr/
A membrane-translocating peptide penetrates into bilayers without significant bilayer perturbations. | Institute for Bioscience...A membrane-translocating peptide penetrates into bilayers without significant bilayer perturbations. | Institute for Bioscience...
Using a high throughput screen, we have identified a family of 12-residue long peptides that spontaneously translocate across membranes. These peptides function by a poorly understood mechanism that is very different from that of the well-known, highly cationic cell penetrating peptides such as the tat peptide from HIV. The newly discovered translocating peptides can carry polar cargoes across synthetic bilayers and across cellular membranes quickly and spontaneously without disrupting the membrane. Here we report on the biophysical characterization of a representative translocating peptide from the selected family, TP2, as well as a negative control peptide, ONEG, from the same library. We measured the binding of the two peptides to lipid bilayers, their secondary structure propensities, their dispositions in bilayers by neutron diffraction, and the response of the bilayer to the peptides. Compared to the negative control, TP2 has a greater propensity for membrane partitioning, although it ...
https://www.ibbr.umd.edu/node/44995
Biomolecules | Free Full-Text | Brownian Motion at Lipid Membranes: A Comparison of Hydrodynamic Models Describing and...Biomolecules | Free Full-Text | Brownian Motion at Lipid Membranes: A Comparison of Hydrodynamic Models Describing and...
The capability of lipid bilayers to exhibit fluid-phase behavior is a fascinating property, which enables, for example, membrane-associated components, such as lipids (domains) and transmembrane proteins, to diffuse within the membrane. These diffusion processes are of paramount importance for cells, as they are for example involved in cell signaling processes or the recycling of membrane components, but also for recently developed analytical approaches, which use differences in the mobility for certain analytical purposes, such as in-membrane purification of membrane proteins or the analysis of multivalent interactions. Here, models describing the Brownian motion of membrane inclusions (lipids, peptides, proteins, and complexes thereof) in model bilayers (giant unilamellar vesicles, black lipid membranes, supported lipid bilayers) are summarized and model predictions are compared with the available experimental data, thereby allowing for evaluating the validity of the introduced models. It will be
https://www.mdpi.com/2218-273X/8/2/30
Repositório Digital de Publicações Científicas: Structure and Phase Transformations of DPPC Lipid Bilayers in thePresence of...Repositório Digital de Publicações Científicas: Structure and Phase Transformations of DPPC Lipid Bilayers in thePresence of...
In this article, we investigate fluid-gel transformations of a DPPC lipid bilayer in the presence of nanoparticles, using coarse grained molecular dynamics. Two types of nanoparticles are considered, specifically a 3 nm hydrophobic nanoparticle located in the core of the bilayer and a 6 nm charged nanoparticle located at the interface between the bilayer and water phase. Both negatively and positively charged nanoparticles at the bilayer interface are investigated. We demonstrate that the presence of all types of nanoparticles induces disorder effects in the structure of the lipid bilayer. These effects are characterized using computer visualization of the gel phase in the presence of nanoparticles, radial distribution functions, and order parameters. The 3 nm hydrophobic nanoparticle immersed in the bilayer core and the positively charged nanoparticle at the bilayer surface have no effect on the temperature of the fluid-gel transformation, compared to the bulk case. Interestingly, a negatively ...
http://rdpc.uevora.pt/handle/10174/3304
Nanodisc Platform for Supported Membrane Protein Based Sensors and Catalysts - NSF-REUNanodisc Platform for Supported Membrane Protein Based Sensors and Catalysts - NSF-REU
1. Wagner ML, Tamm LK (2000) Tethered polymer-supported planar lipid bilayers for reconstitution of integral membrane proteins: silane-polyethyleneglycol-lipid as a cushion and covalent linker. Biophys J 79: 1400-1414.. 2. Sackmann E (1996) Supported membranes: scientific and practical applications. Science 271: 43-48.. 3. Richter RP, Berat R, Brisson AR (2006) Formation of solid-supported lipid bilayers: an integrated view. Langmuir 22: 3497-3505.. 4. Kusters I, Mukherjee N, de Jong MR, Tans S, Koçer A, et al. (2011) Taming Membranes: Functional Immobilization of Biological Membranes in Hydrogels. PLoS ONE 6(5): e20435. doi:10.1371/journal.pone.0020435. 5. Schuler, M. A., Denisov, I. G., Sligar, S. G. (2013) Nanodiscs as a new tool to examine lipid-protein interactions. Methods Mol Biol. 974, 415-433.. 6. Sloan, C. D., Marty, M. T., Sligar, S. G., Bailey, R. C. (2013) Interfacing lipid bilayer nanodiscs and silicon photonic sensor arrays for multiplexed protein-lipid and protein-membrane ...
http://www.engr.uky.edu/nsfreu/reu-research-themes-projects/nanodisc-platform-for-supported-membrane-protein-based-sensors-and-catalysts/
Examining the Origins of the Hydration Force Between Lipid Bilayers Using All-Atom Simulations, The Journal of Membrane Biology...Examining the Origins of the Hydration Force Between Lipid Bilayers Using All-Atom Simulations, The Journal of Membrane Biology...
Read Examining the Origins of the Hydration Force Between Lipid Bilayers Using All-Atom Simulations, The Journal of Membrane Biology on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
https://www.deepdyve.com/lp/springer_journal/examining-the-origins-of-the-hydration-force-between-lipid-bilayers-usq8eN6fyO
Method to disperse lipids as aggregates in oil for bilayers productionMethod to disperse lipids as aggregates in oil for bilayers production
Several techniques to assemble artificial lipid bilayers involve the zipping of monolayers. Their efficiency is determined by the renewal of the saturated monolayers to be zipped and this proceeds by adsorption of lipids dispersed in oil as aggregates. The size of these lipids aggregates is a key parameter to ensure both the stability of the suspension and a fast release of lipids at the interface. We propose a new method inspired from the solvent-shifting nucleation process allowing to control and tune the lipid aggregates size and that improves the production of artificial membranes. It is simpler and faster than current methods starting from a dry lipid film, which are highly sensitive to environmental conditions. This method opens the route to bilayer production processes with new potentialities in membrane composition.
https://hal.archives-ouvertes.fr/L2C/hal-01280723
Dynamical formation of lipid bilayer vesicles from lipid-coated droplets across a planar monolayer at an oil/water interface -...Dynamical formation of lipid bilayer vesicles from lipid-coated droplets across a planar monolayer at an oil/water interface -...
Recently, the transfer method has been shown to be useful for preparing cell-sized phospholipid bilayer vesicles, within which desired substances at desired concentrations can be encapsulated, with a desired asymmetric lipid composition. Here, we investigated the transfer process of water-in-oil (W/O) droplets coat 2013 Hot Papers
http://pubs.rsc.org/en/content/articlelanding/2013/sm/c3sm51766g
Solid-State NMR Literature Blog: J. Am. Chem. Soc., 130 (27), 8856-8864, 2008.Solid-State NMR Literature Blog: J. Am. Chem. Soc., 130 (27), 8856-8864, 2008.
A novel solid-state NMR technique for identifying the asymmetric insertion depths of membrane proteins in lipid bilayers is introduced. By applying Mn2+ ions on the outer but not the inner leaflet of lipid bilayers, the sidedness of protein residues in the lipid bilayer can be determined through paramagnetic relaxation enhancement (PRE) effects. Protein-free lipid membranes with one-side Mn2+-bound surfaces exhibit significant residual 31P and lipid headgroup 13C intensities, in contrast to two-side Mn2+-bound membranes, where lipid headgroup signals are mostly suppressed. Applying this method to a cell-penetrating peptide, penetratin, we found that at low peptide concentrations, penetratin is distributed in both leaflets of the bilayer, in contrast to the prediction of the electroporation model, which predicts that penetratin binds to only the outer lipid leaflet at low peptide concentrations to cause an electric field that drives subsequent peptide translocation. The invalidation of the ...
http://ssnmr.blogspot.com/2008/07/j-am-chem-soc-130-27-88568864-2008.html
Advances in Planar Lipid Bilayers and Liposomes. Volume 6Advances in Planar Lipid Bilayers and Liposomes. Volume 6
Advances in Planar Lipid Bilayers and Liposomes, Volume 6, continues to include invited chapters on a broad range of topics, covering both main arrangements...
https://www.researchandmarkets.com/reports/1756614/advances_in_planar_lipid_bilayers_and_liposomes
Advances in Planar Lipid Bilayers and Liposomes, Volume 5 - 1st EditionAdvances in Planar Lipid Bilayers and Liposomes, Volume 5 - 1st Edition
Purchase Advances in Planar Lipid Bilayers and Liposomes, Volume 5 - 1st Edition. Print Book & E-Book. ISBN 9780123736871, 9780080466545
https://www.elsevier.com/books/advances-in-planar-lipid-bilayers-and-liposomes/leitmannova-liu/978-0-12-373687-1
Viscoelastic deformation of lipid bilayer vesicles - Soft Matter (RSC Publishing)Viscoelastic deformation of lipid bilayer vesicles - Soft Matter (RSC Publishing)
Lipid bilayers form the boundaries of the cell and its organelles. Many physiological processes, such as cell movement and division, involve bending and folding of the bilayer at high curvatures. Currently, bending of the bilayer is treated as an elastic deformation, such that its stress-strain response is i
http://pubs.rsc.org/en/Content/ArticleLanding/2015/SM/c5sm01565k
Vibrational layer eigenmodes of binary phospholipid-cholesterol bilayers at low temperatures<...
TY - JOUR. T1 - Vibrational layer eigenmodes of binary phospholipid-cholesterol bilayers at low temperatures. AU - Leonov, D. V.. AU - Adichtchev, S. V.. AU - Dzuba, S. A.. AU - Surovtsev, N. V.. PY - 2019/2/22. Y1 - 2019/2/22. N2 - Raman spectra in the low-frequency spectral range - between 5 and 90cm-1 - were studied for multilamellar bilayers prepared with cholesterol (Chol) and phospholipids of three different types: doubly unsaturated lipids 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), monounsaturated lipids 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and fully saturated lipids 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). The narrow peak seen below 250 K and positioned between 9 and 18cm-1 - depending on the system and temperature - was attributed to the vibrational eigenmode of a lipid monolayer. For the DOPC-Chol bilayer, the peak position and the peak width were found to monotonically increase and decrease, respectively, with the Chol concentration. For POPC-Chol ...
https://research.nsu.ru/ru/publications/vibrational-layer-eigenmodes-of-binary-phospholipid-cholesterol-b
APS -APS March Meeting 2012 - Event - Domain formation in multicomponent lipid bilayers coupled to elastic substrateAPS -APS March Meeting 2012 - Event - Domain formation in multicomponent lipid bilayers coupled to elastic substrate
We will discuss the physics that governs the lipid localization and domain formation in multicomponent lipid bilayers coupled to an elastic substrate. Lipid localization and domain formation has been studied extensively in biological cell membranes. In this talk we will extend a previous model for membrane energetics to account for the coupling between the bending and the local lipid composition of the two leaflets. Our aim is to determine the relationship between the localization and domain formation in the presence of lipid flip-flops between the two leaflets and the effect of intrinsic curvature of the lipids. Using a lattice model for the membrane, we simulate the system and study the effect of lipid flip-flop on lipid organization in the membrane. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.MAR.B41.15. ...
http://meetings.aps.org/Meeting/MAR12/Event/159849
Continuous Lipid Bilayers Derived from Cell Membranes for Spatial Molecular ManipulationContinuous Lipid Bilayers Derived from Cell Membranes for Spatial Molecular Manipulation
Progress with respect to enrichment and separation of native membrane components in complex lipid environments, such as native cell membranes, has so far been very limited. The reason for the slow progress can be related to the lack of efficient means to generate continuous and laterally fluid supported lipid bilayers (SLBs) made from real cell membranes. We show in this work how the edge of a hydrodynamically driven SLB can be used to induce rupture of adsorbed lipid vesicles of compositions that typically prevent spontaneous SLB formation, such as vesicles made of complex lipid compositions, containing high cholesterol content or being derived from real cell membranes. In particular, upon fusion between the moving edge of a preformed SLB and adsorbed vesicles made directly from 3T3 fibroblast cell membranes, the membrane content of the vesicles was shown to be efficiently transferred to the SLB. The molecular transfer was verified using cholera toxin B subunit (CTB) binding to monosialoganglioside
http://publications.lib.chalmers.se/publication/148776-continuous-lipid-bilayers-derived-from-cell-membranes-for-spatial-molecular-manipulation
THEORY OF SPIN-LATTICE RELAXATION IN LIPID BILAYERS AND BIOLOGICAL MEMBRANES. 2H AND 14N QUADRUPOLAR RELAXATIONTHEORY OF SPIN-LATTICE RELAXATION IN LIPID BILAYERS AND BIOLOGICAL MEMBRANES. 2H AND 14N QUADRUPOLAR RELAXATION
O:13:\PanistOpenUrl\:36:{s:10:\\u0000*\u0000openUrl\;N;s:6:\\u0000*\u0000idc\;N;s:6:\\u0000*\u0000fmt\;s:7:\journal\;s:6:\\u0000*\u0000doi\;s:0:\\;s:6:\\u0000*\u0000pii\;s:0:\\;s:7:\\u0000*\u0000pmid\;s:0:\\;s:9:\\u0000*\u0000atitle\;s:111:\THEORY OF SPIN-LATTICE RELAXATION IN LIPID BILAYERS AND BIOLOGICAL MEMBRANES. 2H AND 14N QUADRUPOLAR ...
https://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=PASCAL83X0405946
Fatty acid transport across lipid bilayer planar membranes | Meta
The transport of palmitic acid (PA) across planar lipid bilayer membranes was measured using a high specific activity [14C]palmitate as tracer for PA. An all-glass trans chamber was employed in order to minimize adsorbance of PA onto the surface. Electrically neutral (diphytanoyl phosphatidylcholine) and charged (Azolectin) planar bilayers were maintained at open electric circuit. We found a permeability to PA of (8.8 +/- 1.9) x 10(-6) cm s(-1) (n = 15) in neutral and of (10.3 +/- 2.2) x 10(-6) cm s(-1) (n = 5) in charged bilayers. These values fall within the order of magnitude of those calculated from desorption constants of PA in different vesicular systems. Differences between data obtained from planar and vesicular systems are discussed in terms of the role of solvent, radius of curvature, and pH changes. ...
https://www.meta.org/papers/fatty-acid-transport-across-lipid-bilayer-planar/10695921
artificial lipid bilayer membrane Archives - Janta Ka Reporter 2.0artificial lipid bilayer membrane Archives - Janta Ka Reporter 2.0
Jantakareporter.com is an independent news website covering the latest trends from India and around the world. Our team of hard-working and dedicated journalists gather news, verify their authenticity before showcasing them on our website for your consumption. The purpose of launching Jantakareporter.com, a 24×7 multimedia website is to revolutionize the way we gather news ...
http://www.jantakareporter.com/tag/artificial-lipid-bilayer-membrane/
Onsagers variational principle in soft matter: introduction and application to the dynamics of adsorption of proteins onto...Onsagers variational principle in soft matter: introduction and application to the dynamics of adsorption of proteins onto...
Lipid bilayers are unique soft materials operating in general in the low Reynolds limit. While their shape is predominantly dominated by curvature elasticity as in a solid shell, their in-plane behavior is that of a largely inextensible viscous fluid. Furthermore, lipid membranes are extremely responsive to chemical stimuli. Because in their biological context they are continuously brought out-of-equilibrium mechanically or chemically, it is important to understand their dynamics. Here, we introduce Onsagers variational principle as a general and transparent modeling tool for lipid bilayer dynamics. We introduce this principle with elementary examples, and then use it to study the sorption of curved proteins on lipid membranes.. Link to Chapter ...
https://torres-sanchez.xyz/?p=100
TEL - Thèses en ligne - Molecular interaction of natural compounds with lipid bilayer membranes : Towards a better...TEL - Thèses en ligne - Molecular interaction of natural compounds with lipid bilayer membranes : Towards a better...
One of the key lockers to understand mechanisms of biological action of drugs and natural compounds is their capacity to incorporate/cross lipid bilayer membranes. In the light of demanding experimental techniques, in silico molecular modelling has become a powerful alternative to tackle these issues. In the past few years, molecular dynamics (MD) has opened many perspectives, providing an atomistic description of the related intermolecular interactions. Using MD simulations, we have explored the capacity of several compounds (polyphenols, vitamins E and C, plantazolicin, carprofens) to incorporate lipid bilayer membranes. The different compounds were chosen according to their different biological functions, namely (i) antioxidant activity against lipid peroxidation, (ii) antimicrobial activity with the possibility of trans-membrane pore formation, and (iii) inhibition of enzymes involved in Alzheimers disease. In order to rationalize their mechanisms of action, their position and orientation in
https://tel.archives-ouvertes.fr/tel-01659919
Terminal lipophilization of a unique DNA dodecamer by various nucleolipid headgroups: Their incorporation into artificial lipid...Terminal lipophilization of a unique DNA dodecamer by various nucleolipid headgroups: Their incorporation into artificial lipid...
Terminal lipophilization of a unique DNA dodecamer by various nucleolipid headgroups: Their incorporation into artificial lipid bilayers and hydrodynamic properties
https://www.beilstein-journals.org/bjoc/articles/11/103
Download Advances in Planar Lipid Bilayers and Liposomes, Volume 7 by A. Leitmannova Liu PDF - Avada XML Book Archive
9] L. Movileanu, D. Popescu, S. I. Popescu, Transbilayer pores induced by thickness fluctuations, Bull. Math. Biol. 68 (2006) 1231-1255. V. Zhelev, D. Needham, Tension-stabilized pores in giant vesicles: Determination of pore size and pore line tension, Biochim. Biophys. Acta 1147 (1993) 89-104. [11] M. Winterhalter, W. Helfrich, Effect of voltage on pores in membranes, Phys. Rev. A 36 (1987) 5874-5876. Random Processes in the Appearance and Dynamics of an Electropore 33 [12] E. Neumann, M. Schaefer-Ridder, Y. Frey, Polymorphism of monolayers of monomeric and macromolecular lipids: On the defect structure of crystalline phases and the possibility of hexatic order formation in physics of amphiphilic layers, in: J. Meunier, D. Langevin, V. ), Physics of amphiphilic layers, Springer, Berlin (1987). [43] M. Langner, H. Pruchnik, K. Kubica, The effect of the lipid bilayer state on fluorescence intensity of fluorescein-PE in a saturated lipid bilayer, Z. Naturforsch. 55 (2000) 418-424. [44] K. Kubica, ...
http://exposurebiz.com/lib/advances-in-planar-lipid-bilayers-and-liposomes-volume-7
Infrared Spectroscopy of Fluid Lipid BilayersInfrared Spectroscopy of Fluid Lipid Bilayers
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https://www.infona.pl/resource/bwmeta1.element.acs-doi-10_1021_ac050990c
Supplementary MaterialsSupplementary Information 41598 2017 4219 MOESM1 ESM. in lipid bilayers. Additionally, the DNP...Supplementary MaterialsSupplementary Information 41598 2017 4219 MOESM1 ESM. in lipid bilayers. Additionally, the DNP...
Supplementary MaterialsSupplementary Information 41598_2017_4219_MOESM1_ESM. in lipid bilayers. Additionally, the DNP sensitivity-enhanced two-dimensional 13C/13C chemical shift correlations via proton AUY922 inhibition driven spin diffusion offered length constraints to characterize protein-lipid interactions and uncovered the transmembrane topology of cytochrome b5. The outcomes reported in this research would pave methods for high-quality structural and topological investigations of membrane-bound full-duration bitopic proteins complexes under physiological circumstances. Launch Bitopic membrane proteins with an KI67 antibody individual membrane-spanning -helix represent over fifty percent of most membrane proteins, which contain approximately 1 / 3 of all open up reading frames (ORFs), in individual AUY922 inhibition genomes1C3. Their dynamic protein-proteins and protein-ligand interactions in the membrane environment play various vital functions in the cellular procedures connected with ...
http://www.thetechnoant.info/2019/11/24/supplementary-materialssupplementary-information-41598_2017_4219_moesm1_esm-in-lipid-bilayers-additionally-the-dnp-sensitivity-enhanced/
Molecular Dynamic Simulations of Biological MembranesMolecular Dynamic Simulations of Biological Membranes
Biological membranes mainly constituent lipid molecules along with some proteins and steroles. The properties of the pure lipid bilayers as well as in the presence of other constituents (in case of two or three component systems) are very important to be studied carefully to model these systems and compare them with the realistic systems. Molecular dynamic simulations provide a good opportunity to model such systems and to study them at microscopic level where experiments fail to do. In this thesis we study the structural and dynamic properties of the pure phospholipid bilayers and the phase behavior of phospholipid bilayers when other constituents are present in them. Material and structural properties like area per lipid and area compressibility of the phospholipids show a big scatter in experiments. These properties are studied for different system sizes and it was found that the increasing undulations in large systems effect these properties. A correction was applied to area per lipid and ...
http://kth.diva-portal.org/smash/record.jsf?pid=diva2:551948
Biotechnological Application of Membrane Proteins Reconstituted Into Vesicular and Planar Lipid Bilayers | Springer for...Biotechnological Application of Membrane Proteins Reconstituted Into Vesicular and Planar Lipid Bilayers | Springer for...
Proteins and lipids are the building blocks of biological membranes. In the past and at present, only the lipids in the form of bilayers, vesicles, and thin films found/find applications in...
https://rd.springer.com/chapter/10.1007/978-1-4684-7908-9_21
Comparative Study of the Condensing Effects of Ergosterol and CholesterolComparative Study of the Condensing Effects of Ergosterol and Cholesterol
Cholesterol, due to its condensing effect, is considered an important regulator of membrane thickness. Other sterols, due to their structural similarities to cholesterol, are often assumed to have a universal effect on membrane properties similar to the condensing effect of cholesterol, albeit possibly to different degrees. We used x-ray diffraction to investigate this assumption. By the combination of lamellar diffraction and grazing-angle scattering, we measured the membrane thickness and the tilt-angle distribution of the lipids hydrocarbon chains. This method is sensitive to phase separation, which is important for examining the miscibility of sterols and phospholipids. Mixtures of ergosterol or cholesterol with dimyristoylphosphatidylcholine, palmitoyloleoylphosphatidylcholine, and dioleoylphosphatidylcholine were systematically studied. We found that mixing ergosterol with phospholipids into a single phase became increasingly difficult with higher sterol concentrations and also with ...
https://scholarship.rice.edu/handle/1911/90924
NMR studies of membranes composed of glycolipids and phospholipidsNMR studies of membranes composed of glycolipids and phospholipids
This thesis deals with the study of lipid bilayer systems by solid-state nuclear magnetic resonance. Two-dimensional 1H-13C separated local field experiments under magic-angle spinning were employed to investigate structural and dynamical modifications of cell membranes, resulting from the addition of compounds with some biological relevance. For further interpretation of the segmental order obtained from the 2D experiments other methods, such as 31P-NMR, 2H-NMR and molecular dynamics simulations, were also employed. The work presented in this thesis can be divided into two parts. The first part refers to the setup of experimental conditions. Heating and hydration effects were addressed in order to define both the temperature of the system as well as the number of water molecules per lipid necessary to fully hydrate the bilayer. Application of this experimental setup to lipid membrane systems with biological relevance constitutes the second part. The interaction of monogalactosyl- ...
http://su.diva-portal.org/smash/record.jsf?pid=diva2:198823
Lipid liquid-crystalline nanostructure and biomolecular interactions - Fakultät für Physik - LMU München
Biological membranes do not only occur as planar bilayer structures, but bilayers have also been shown to, depending on the lipid composition, curve into intriguing 3D structures. Understanding the biological implication as well as the application of such interfaces, for e.g. drug delivery and other biomedical application, requires the development of well-defined model system.. We have shown that spin-coating the constituting lipids followed by hydration of the lipid layer can be used to form non-lamellar liquid crystalline surfaces of different types on the surface. In order to make the layers more responsive polymer micro-gels with a diameter of about 55 nm can be embedded within the layer. Another way to for non-planar lipid interfaces are to deposit lipids on nanostructured surfaces. Here we demonstrate the formation of fluid supported bilayers on vertical gallium phosphide nanowire (NW) forests using self-assembly from lipid vesicular dispersions.1 The phospholipid mixture used had a ...
http://www.physik.uni-muenchen.de/aus_der_fakultaet/kolloquien/cens_seminar/archiv_sose16/160429_nylander/
Search | Open Access Kent State (OAKS)Search | Open Access Kent State (OAKS)
The combined effects of the tendency of cholesterol to order lipids in the liquid phase and the coupling between lipids in the two leaves of a bilayer are investigated theoretically utilizing a Landau free energy. We show that as a consequence of these combined effects, lateral phase separation in the outer leaf between cholesterol-rich and -poor liquids causes a similar, but weaker, phase separation in the inner leaf. Just as the areal density of lipids in the outer leaf increases in the cholesterol-rich regions, so the areal density of lipids also increases in the inner leaf. Thus, the areal density in the inner leaf varies spatially, reflecting spatial variations of the areal density in the outer leaf. This provides a mechanism for proteins attached to the inner leaf via a hydrocarbon tether to respond to variations in the composition of the outer leaf. We also note that the effect of coupling between the leaves should be observable in artificial bilayers.. ...
https://oaks.kent.edu/search?f%5B0%5D=keyword%3A5835&f%5B1%5D=keyword%3A5836&sort_by=date_string
Search | Open Access Kent State (OAKS)Search | Open Access Kent State (OAKS)
The combined effects of the tendency of cholesterol to order lipids in the liquid phase and the coupling between lipids in the two leaves of a bilayer are investigated theoretically utilizing a Landau free energy. We show that as a consequence of these combined effects, lateral phase separation in the outer leaf between cholesterol-rich and -poor liquids causes a similar, but weaker, phase separation in the inner leaf. Just as the areal density of lipids in the outer leaf increases in the cholesterol-rich regions, so the areal density of lipids also increases in the inner leaf. Thus, the areal density in the inner leaf varies spatially, reflecting spatial variations of the areal density in the outer leaf. This provides a mechanism for proteins attached to the inner leaf via a hydrocarbon tether to respond to variations in the composition of the outer leaf. We also note that the effect of coupling between the leaves should be observable in artificial bilayers.. ...
https://oaks.kent.edu/search?f%5B0%5D=community%3A21855&f%5B1%5D=keyword%3A5838&sort_by=title
Diffusion limitation in the block by symmetric tetraalkylammonium ions of anthrax toxin channels in planar phospholipid bilayer...Diffusion limitation in the block by symmetric tetraalkylammonium ions of anthrax toxin channels in planar phospholipid bilayer...
TY - JOUR. T1 - Diffusion limitation in the block by symmetric tetraalkylammonium ions of anthrax toxin channels in planar phospholipid bilayer membranes. AU - Blaustein, Robert O.. AU - Finkelstein, Alan. PY - 1990/11. Y1 - 1990/11. N2 - Current flow through the channel formed in planar phospholipid bilayer membranes by the PA65 fragment of anthrax toxin is blocked, in a voltage-dependent manner, by tetraalkylammonium ions (at micromolar concentrations), which bind to a blocking site within the channel lumen. We have presented evidence that diffusion plays a significant role in the kinetics of blocking by tetrabutylammonium ion (Bu4N+) from the cis (toxin-containing) side of the membrane (Blaustein, R. O., E. J. A. Lea, and A. Finkelstein. 1990. J. Gen. Physiol. 96:921-942); in this paper we examine the implications and consequences of diffusion control for binding kinetics. As expected for a diffusion-affected reaction, both the entry rate constant (k1cis) of Bu4N+ from the cis solution to the ...
https://einstein.pure.elsevier.com/en/publications/diffusion-limitation-in-the-block-by-symmetric-tetraalkylammonium-2
Coarse-grained molecular dynamics simulations of the energetics of helix insertion into a lipid bilayer. - Oxford Neuroscience
Experimental and computational studies have indicated that hydrophobicity plays a key role in driving the insertion of transmembrane alpha-helices into lipid bilayers. Molecular dynamics simulations allow exploration of the nature of the interactions of transmembrane alpha-helices with their lipid bilayer environment. In particular, coarse-grained simulations have considerable potential for studying many aspects of membrane proteins, ranging from their self-assembly to the relation between their structure and function. However, there is a need to evaluate the accuracy of coarse-grained estimates of the energetics of transmembrane helix insertion. Here, three levels of complexity of model system have been explored to enable such an evaluation. First, calculated free energies of partitioning of amino acid side chains between water and alkane yielded an excellent correlation with experiment. Second, free energy profiles for transfer of amino acid side chains along the normal to a phosphatidylcholine
https://www.neuroscience.ox.ac.uk/publications/100612
Calorimetric and theoretical studies of the effects of lindane on lipid bilayers of different acyl chain length - Staff of the...Calorimetric and theoretical studies of the effects of lindane on lipid bilayers of different acyl chain length - Staff of the...
The effects of the insecticide lindane on the phase transition in multilamellar bilayers of saturated diacylphosphatidylcholines of different acyl chain length (DC14PC, DC16PC, and DC18PC) have been studied by means of differential scanning calorimetry (DSC), as well as computer-simulation calculations on a molecular interaction model. The calorimetric data show that increasing concentrations of lindane lower the transition temperature and lead to a broadening of the specific heat in a systematic way depending on the lipid acyl chain length. Kinetic effects in the observed calorimetric traces indicate that the incorporation of lindane into multilamellar lipid bilayers is slow, but faster for the shorter lipid species. Large unilamellar vesicles do not show such kinetic effects. The transition enthalpy is for all three lipid species found to be independent of the lindane concentration which implies that the entropy of mixing is vanishingly small. This lends support to a microscopic molecular ...
https://food.ku.dk/english/staff/?pure=en%2Fpublications%2Fcalorimetric-and-theoretical-studies-of-the-effects-of-lindane-on-lipid-bilayers-of-different-acyl-chain-length
Lipid fluorination enables phase separation from fluid phospholipid bilayers<...Lipid fluorination enables phase separation from fluid phospholipid bilayers<...
TY - JOUR. T1 - Lipid fluorination enables phase separation from fluid phospholipid bilayers. AU - Webb, S. J.. AU - Greenway, K.. AU - Bayati, M.. AU - Trembleau, Laurent Alain Claude. PY - 2006/5. Y1 - 2006/5. N2 - To probe the effect of lipid fluorination on the formation of lipid domains in phospholipid bilayers, several new fluorinated and non-fluorinated synthetic lipids were synthesised, and the extent of phase separation of these lipids from phospholipid bilayers of different compositions was determined. At membrane concentrations as low as 1% mol/mol, both fluorinated and non-.uorinated lipids were observed to phase separate from a gel-phase ( solid ordered) phospholipid matrix, but bilayers in a liquid disordered state caused no phase separation; if the gel-phase samples were heated above the transition temperature, then phase separation was lost. We found incorporation of perfluoroalkyl groups into the lipid enhanced phase separation, to such an extent that phase separation was ...
https://abdn.pure.elsevier.com/en/publications/lipid-fluorination-enables-phase-separation-from-fluid-phospholip
Assembly of RNA nanostructures on supported lipid bilayersAssembly of RNA nanostructures on supported lipid bilayers
The assembly of nucleic acid nanostructures with controlled size and shape has large impact in the fields of nanotechnology, nanomedicine and synthetic biology. The directed arrangement of nano-structures at interfaces is important for many applications. In spite of this, the use of laterally mobile lipid bilayers to control RNA three-dimensional nanostructure formation on surfaces remains largely unexplored. Here, we direct the self-assembly of RNA building blocks into three-dimensional structures of RNA on fluid lipid bilayers composed of cationic 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) or mixtures of zwitterionic 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC) and cationic sphingosine. We demonstrate the stepwise supramolecular assembly of discrete building blocks through specific and selective RNA-RNA interactions, based on results from quartz crystal microbalance with dissipation (QCM-D), ellipsometry, fluorescence recovery after photobleaching (FRAP) and total internal reflection
http://publications.lib.chalmers.se/publication/211730-assembly-of-rna-nanostructures-on-supported-lipid-bilayers
Supported double bilayers: an experimental model to probe biomembrane properties (MSc Niek de Lange) - WURSupported double bilayers: an experimental model to probe biomembrane properties (MSc Niek de Lange) - WUR
Progress in theoretical modelling (our group has performed molecularly detailed self-consistent field (SCF) calculations on lipid bilayer membranes) in combination with advanced and cutting-edge techniques have enabled us to perform more advanced experiments on lipid bilayers. This makes it possible to determine on how lipids and other membrane constituents organise the delicate force balances in bilayers that are responsible for the structure and structural (in)stability.. The aim of this PhD project is to develop an experimental membrane platform to determine mechanical properties and topological integrity of lipid membranes of increasing complexity. The experimental platform comprises of a supported double lipid membrane in a flow cell, mounted in a set-up including a TIRF microscope and an AFM dedicated to force measurements. The influence of various perturbing stimuli, such as edge-active agents, antimicrobial peptides and nanoparticles, on these membrane properties will be investigated. ...
https://www.wur.nl/en/project/Supported-double-bilayers-an-experimental-model-to-probe-biomembrane-properties-MSc-Niek-de-Lange-1.htm
Assembly of α-synuclein aggregates on phospholipid bilayers<...
TY - JOUR. T1 - Assembly of α-synuclein aggregates on phospholipid bilayers. AU - Lv, Zhengjian. AU - Hashemi, Mohtadin. AU - Banerjee, Siddhartha. AU - Zagorski, Karen. AU - Rochet, Jean Christophe. AU - Lyubchenko, Yuri L.. N1 - Funding Information: The work at the University of Nebraska Medical Center (UNMC) was supported by grants from the National Institutes of Health to Y.L.L. ( R01 GM096039 , R01GM118006 and R21 NS101504 ). J.C.R. was supported by the Branfman Family Foundation . M.H. was partially supported by the UNMC Graduate Fellowship. The computational modeling was partially performed using resources at the Holland Computing Center of the University of Nebraska, which receives support from the Nebraska Research Initiative . Anton 2 computer time was provided by the Pittsburgh Supercomputing Center (PSC) through Grant R01GM116961 from the National Institutes of Health. The Anton 2 machine at PSC was generously made available by D.E. Shaw Research. The authors thank Melody A. ...
https://experts.nebraska.edu/en/publications/assembly-of-%CE%B1-synuclein-aggregates-on-phospholipid-bilayers
BIOPHYSICS SEMINAR |br| The Good, The Bad, and The Ugly: Charges and Their Role in Lipid Phase Separation | U-M LSA PhysicsBIOPHYSICS SEMINAR |br| The Good, The Bad, and The Ugly: Charges and Their Role in Lipid Phase Separation | U-M LSA Physics
Recent literature has shown that buffers affect the interaction between lipid bilayers through a mechanism that involves van der Waals forces, electrostatics, hydration forces and membrane bending rigidity. This talk will highlight our recent work that shows phase coexistence can be a result of Goods buffer charges on the mixed chain 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid bilayers. Since the two phases must be in osmotic equilibrium with one another, this behavior challenges theoretical models of lipid interactions and introduces new variables to consider for the Gibbs phase rule. This model of lipid charging was then used to explain the mechanisms behind phase separation in lipid mixtures containing charged lipid head groups, particularly phosphatidylinositols. Furthermore, this work is then applied to our understanding of underlying mechanisms involved in membrane protein selective association with phosphoinositols, and later re-organization of these membranes. This work ...
https://prod.lsa.umich.edu/physics/news-events/all-events/archived-events/biophysics-seminar/biophysics-seminar--br--the-good--the-bad--and-the-ugly--charges.html
The effect of the protein corona on the interaction between nanoparticles and lipid bilayers. - Semantic ScholarThe effect of the protein corona on the interaction between nanoparticles and lipid bilayers. - Semantic Scholar
HYPOTHESIS It is known that nanoparticles (NPs) in a biological fluid are immediately coated by a protein corona (PC), composed of a hard (strongly bounded) and a soft (loosely associated) layers, which represents the real nano-interface interacting with the cellular membrane in vivo. In this regard, supported lipid bilayers (SLB) have extensively been used as relevant model systems for elucidating the interaction between biomembranes and NPs. Herein we show how the presence of a PC on the NP surface changes the interaction between NPs and lipid bilayers with particular care on the effects induced by the NPs on the bilayer structure. EXPERIMENTS In the present work we combined Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D) and Neutron Reflectometry (NR) experimental techniques to elucidate how the NP-membrane interaction is modulated by the presence of proteins in the environment and their effect on the lipid bilayer. FINDINGS Our study showed that the NP-membrane interaction is
https://www.semanticscholar.org/paper/The-effect-of-the-protein-corona-on-the-interactio-Silvio-Maccarini/93b3074f1f83e53886f472fd8d5451f6fda1341b
Lipid bilayer - Simple English Wikipedia, the free encyclopediaLipid bilayer - Simple English Wikipedia, the free encyclopedia
Lipid bilayers are important in biological cells. They are the basis of cell membranes, and they surround most cell organelles. Lipid bilayers form automatically from phospholipids by self-assembly. The phospholipids have heads which mix with water and tails which reject water. So the tails come together in the centre of the double layer, and the heads on the outside are surrounded by water. The lipid bilayers stop most water-soluble (hydrophilic) molecules passing through. They also stop most ions. In cells, proteins are put in the bilayer by enzymes. The proteins decide which molecules come in and which go out of the cell. For example, cells control salt concentrations and pH by pumping ions across their membranes using proteins called ion pumps. ...
https://simple.wikipedia.org/wiki/Phospholipid_bilayer
Functional surface engineering by nucleotide-modulated potassium channel insertion into polymer membranes attached to solid...Functional surface engineering by nucleotide-modulated potassium channel insertion into polymer membranes attached to solid...
Planar solid-supported membranes based on amphiphilic block copolymers represent promising systems for the artificial creation of structural surfaces. Here we introduce a method for engineering functional planar solid-supported membranes through insertion of active biomolecules. We show that membranes based on poly(dimethylsiloxane)-block-poly(2-methyl-2-oxazoline) (PDMS-b-PMOXA) amphiphilic diblock copolymers, which mimic natural membranes, are suitable for hosting biomolecules. Our strategy allows preparation of large-area, well-ordered polymer bilayers via Langmuir-Blodgett and Langmuir-Schaefer transfers, and insertion of biomolecules by using Bio-Beads. We demonstrate that a model membrane protein, the potassium channel from the bacterium Mesorhizobium loti, remains functional after insertion into the planar solid-supported polymer membrane. This approach can be easily extended to generate a platform of functional solid-supported membranes by insertion of different hydrophobic biomolecules, ...
https://edoc.unibas.ch/35074/
General hydrophobic interaction potential for surfactant/lipid bilayers from direct force measurements between light-modulated...General hydrophobic interaction potential for surfactant/lipid bilayers from direct force measurements between light-modulated...
Descrição: We establish and quantify correlations among the molecular structures, interaction forces, and physical processes associated with light-responsive self-assembled surfactant monolayers or bilayers at interfaces. Using the surface forces apparatus (SFA), the interaction forces between adsorbed monolayers and bilayers of an azobenzene-functionalized surfactant can be drastically and controllably altered by light-induced conversion of trans and cis molecular conformations. These reversible conformation changes affect significantly the shape of the molecules, especially in the hydrophobic region, which induces dramatic transformations of molecular packing in self-assembled structures, causing corresponding modulation of electrostatic double layer, steric hydration, and hydrophobic interactions. For bilayers, the isomerization from trans to cis exposes more hydrophobic groups, making the cis bilayers more hydrophobic, which lowers the activation energy barrier for (hemi)fusion. A ...
http://www.buscaintegrada.usp.br/primo_library/libweb/action/display.do?tabs=detailsTab&gathStatTab=true&ct=display&fn=search&doc=TN_medline21896718&indx=1&recIds=TN_medline21896718&recIdxs=0&elementId=0&renderMode=poppedOut&displayMode=full&frbrVersion=4&rfnGrpCounter=1&vl
Chiral Recognition of Lipid Bilayer Membranes by Supramolecular Assemblies of Peptide Amphiphiles<...
TY - JOUR. T1 - Chiral Recognition of Lipid Bilayer Membranes by Supramolecular Assemblies of Peptide Amphiphiles. AU - Sato, Kohei. AU - Ji, Wei. AU - Álvarez, Zaida. AU - Palmer, Liam C.. AU - Stupp, Samuel I.. PY - 2019/6/10. Y1 - 2019/6/10. N2 - On the basis of the exclusive existence of homochirality in biomolecules and the well-known phenomenon of chiral recognition, it is obvious that chirality is a crucial factor in biological events. We report here that supramolecular assemblies of peptide amphiphiles interact with lipid bilayer membranes in a stereospecific manner. When negatively charged chiral phospholipid bilayer vesicles were subjected to the assemblies, we found that peptide amphiphiles with l-amino acids show stronger affinity for the liposomes compared to the ones with d-amino acids. To examine their biological functions, we tested the cytotoxicity of nanofibers against mammalian primary cells using human bone marrow mesenchymal stem cells and murine astroglial cells. We ...
https://sofi-northwestern.pure.elsevier.com/en/publications/chiral-recognition-of-lipid-bilayer-membranes-by-supramolecular-a
Reconstitution of vacuolar ion channels into planar lipid bilayers
Klughammer, B., Benz, B., Betz, M., Thume, M., & Dietz, K. - J. (1992). Reconstitution of vacuolar ion channels into planar lipid bilayers. Biochimica et Biophysica Acta, 1104(2), 308-316. doi:10.1016/0005-2736(92)90045- ...
https://pub.uni-bielefeld.de/publication/1866725
Thermally induced phase separation in supported bilayers of glycosphingolipid and phospholipid mixtures | Biointerphases | Full...Thermally induced phase separation in supported bilayers of glycosphingolipid and phospholipid mixtures | Biointerphases | Full...
The authors have studied microstructure evolution during thermally induced phase separation in a class of binary supported lipid bilayers using a quantitative application of imaging ellipsometry. The bilayers consist of binary mixtures consisting of a higher melting glycosphingolipid, galactosylceramide (GalCer), which resides primarily in the outer leaflet, and a lower melting, unsaturated phospholipid, 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC). Three different bilayer compositions of GalCer/DLPC mixtures at 35:65, 20:80, and 10:90 molar ratios were cooled at controlled rates from their high-temperature homogeneous phase to temperatures corresponding to their phase coexistence regime and imaged in real time using imaging ellipsometry. During the thermotropic course of GalCer gelation, we find that two distinct types of morphological features modulate. First, the formation and growth of chain and fractal-like defects ascribed to the net change in molecular areas during the phase transition. The
https://biointerphases.springeropen.com/articles/10.1116/1.3524295
Theory of modulated phases in lipid bilayers and liquid crystal films<...Theory of modulated phases in lipid bilayers and liquid crystal films<...
TY - JOUR. T1 - Theory of modulated phases in lipid bilayers and liquid crystal films. AU - Chen, C. M.. AU - MacKintosh, F. C.. N1 - Copyright: Copyright 2017 Elsevier B.V., All rights reserved.. PY - 1996. Y1 - 1996. N2 - We present a general theory for equilibrium-modulated phases of chiral and achiral bilayer membranes and liquid crystal films. Both bulk smectics as well as freely suspended films are considered. For flexoelectric systems, continuous structural phase transitions are predicted among square-lattice, hexagonal, and distorted two-dimensional modulated phases as a function of the applied electric field. It is also shown that only uniform flat phases are predicted for thin films. One-dimensional ripple phases and two-dimensional square-lattice phases can occur with increasing film thickness.. AB - We present a general theory for equilibrium-modulated phases of chiral and achiral bilayer membranes and liquid crystal films. Both bulk smectics as well as freely suspended films are ...
https://scholar.lib.ntnu.edu.tw/zh/publications/theory-of-modulated-phases-in-lipid-bilayers-and-liquid-crystal-f
Impact of cholesterol on voids in phospholipid membranes<...Impact of cholesterol on voids in phospholipid membranes<...
TY - JOUR. T1 - Impact of cholesterol on voids in phospholipid membranes. AU - Falck, E.. AU - Patra, M.. AU - Karttunen, M.E.J.. AU - Hyvönen, M.T.. AU - Vattulainen, I.. PY - 2004. Y1 - 2004. N2 - Free volume pockets or voids are important to many biological processes in cell membranes. Free volume fluctuations are a prerequisite for diffusion of lipids and other macromolecules in lipid bilayers. Permeation of small solutes across a membrane, as well as diffusion of solutes in the membrane interior are further examples of phenomena where voids and their properties play a central role. Cholesterol has been suggested to change the structure and function of membranes by altering their free volume properties. We study the effect of cholesterol on the properties of voids in dipalmitoylphosphatidylcholine (DPPC) bilayers by means of atomistic molecular dynamics simulations. We find that an increasing cholesterol concentration reduces the total amount of free volume in a bilayer. The effect of ...
https://research.tue.nl/en/publications/impact-of-cholesterol-on-voids-in-phospholipid-membranes
Durability of oxygen evolution of photosystem II incorporated into lipid bilayers<...
TY - JOUR. T1 - Durability of oxygen evolution of photosystem II incorporated into lipid bilayers. AU - Noji, Tomoyasu. AU - Kondo, Masaharu. AU - Kawakami, Keisuke. AU - Shen, Jian Ren. AU - Nango, Mamoru. AU - Dewa, Takehisa. PY - 2014/11. Y1 - 2014/11. N2 - Photosystem II (PSII) has attracted a lot of attention for use in the construction of artificial photosynthetic materials due to its high activity of oxidation of water molecules. However, the robustness of PSII needs to be improved for in vitro application. In this study, we incorporated PSII (Thermosynechococcus vulcanus) into various phospholipid membranes to examine the activity and durability of oxygen evolution. PSII was incorporated into anionic 1,2-dioleoyl-sn-glycero-3-phospho-(1-rac-glycerol) (PSII-DOPG), zwitterionic 1,2-dioleoyl-sn-glycero-3-phosphocholine (PSII-DOPC), and cationic 1,2-dioleoyl-sn-glycero-3-ethylphosphocholine (PSII-EDOPC). Structural integrity of PSII was examined by absorption and fluorescence spectroscopy. ...
https://okayama.pure.elsevier.com/en/publications/durability-of-oxygen-evolution-of-photosystem-ii-incorporated-int
徳島大学 / 教育研究者総覧 --- 後藤 優樹徳島大学 / 教育研究者総覧 --- 後藤 優樹
We investigated the thermotropic phase behavior of the distearoylphosphatidylcholine (DSPC)-cholesterol binary bilayer membrane as a function of the cholesterol composition (X(ch)) by fluorescence spectroscopy using 6-propionyl-2-(dimethylamino)naphthalene (Prodan) and differential scanning calorimetry (DSC). The fluorescence spectra, each of which has a single maximum, showed that the wavelength at the maximum intensity (lambda(max)) changed depending on the bilayer state: ca. 440 nm for the lamellar gel (L(beta) or L(beta)) and the liquid ordered (L(o)) phases, ca. 470 nm for the ripple gel (P(beta)) phase and ca. 490 nm for the liquid crystalline (L(alpha)) phase, respectively. The transition temperatures were determined from the temperature dependences of the lambda(max) and endothermic peaks of the DSC thermograms. Both measurements showed that the pretransition disappears around X(ch)=0.035. The constructed temperature-X(ch) phase diagram indicated that the phase behavior of the binary ...
http://pub2.db.tokushima-u.ac.jp/ERD/person/174530/work-ja.html
Solid-Supported Synthesis of Glycoconjugates | Bentham ScienceSolid-Supported Synthesis of Glycoconjugates | Bentham Science
Carbohydrate-protein interactions play a major-role in recognition of cells by external macromolecules. Single saccharide ligands, however, bind only weakly to their protein receptors. Sufficient affinity is achieved by appropriate mutual orientation of the saccharide epitopes and their protein receptors, which allows multiple simultaneous interactions. In other words, high affinity binding is achieved through multivalency, where the high number of simultaneous binding events compensates the lack of strength of an individual interaction. Solid-supported methods allowing synthesis of multiantennary glycoconjugates have, hence, been under active development. The present paper is a review of the solid-phase protocols useful for preparation of glycoconjugates. ...
https://www.eurekaselect.com/106373/chapter/solid-supported-synthesis-of-glycoconjugate
Effects of hydrostatic pressure on the molecular structure and endothermic phase transitions of phosphatidylcholine bilayers: a...Effects of hydrostatic pressure on the molecular structure and endothermic phase transitions of phosphatidylcholine bilayers: a...
Effects of hydrostatic pressure on the molecular structure and endothermic phase transitions of phosphatidylcholine bilayers: a Raman scattering study
https://publications-cnrc.canada.ca/eng/view/object/?id=5be47de9-5b9e-45f9-bca1-d79941085d22
All Faculty | Duke Mechanical Engineering and Materials ScienceAll Faculty | Duke Mechanical Engineering and Materials Science
The effects of the cholesterol analog 5α-cholestan-3β-ol-6-one (6-ketocholestanol) on bilayer structure, bilayer cohesive properties, and interbilayer repulsive pressures have been studied by a combination of X-ray diffraction, pipette aspiration, and dipole potential experiments. It is found that 6-ketocholestanol, which has a similar structure to cholesterol except with a keto moiety at the 6 position of the B ring, has quite different effects than cholesterol on bilayer organization and cohesive properties. Unlike cholesterol, 6-ketocholestanol does not appreciably modify the thickness of liquid-crystalline egg phosphatidylcholine (EPC) bilayers, and causes a much smaller increase in bilayer compressibility modulus than does cholesterol. These data imply that 6-ketocholestanol has both its hydroxyl and keto moieties situated near the water-hydrocarbon interface, thus making its orientation in the bilayer different from cholesterols Keywords: ...
http://fds.duke.edu/db/pratt/mems/faculty/d.needham/publications/55893
Asymmetric phospholipid: Lipopolysaccharide bilayers; a Gram-negative bacterial outer membrane mimic<...
TY - JOUR. T1 - Asymmetric phospholipid. T2 - Lipopolysaccharide bilayers; a Gram-negative bacterial outer membrane mimic. AU - Clifton, Luke A.. AU - Skoda, Maximilian W. A.. AU - Daulton, Emma L.. AU - Hughes, Arwel V.. AU - Le Brun, Anton P.. AU - Lakey, Jeremy. H.. AU - Holt, Stephen A.. PY - 2013/12/6. Y1 - 2013/12/6. N2 - The Gram-negative bacterial outer membrane (OM) is a complex and highly asymmetric biological barrier but the small size of bacteria has hindered advances in in vivo examination of membrane dynamics. Thus, model OMs, amenable to physical study, are important sources of data. Here, we present data from asymmetric bilayers which emulate the OM and are formed by a simple two-step approach. The bilayers were deposited on an SiO2 surface by Langmuir-Blodgett deposition of phosphatidylcholine as the inner leaflet and, via Langmuir-Schaefer deposition, an outer leaflet of either Lipid A or Escherichia coli rough lipopolysaccharides (LPS). The membranes were examined using ...
https://researchportal.bath.ac.uk/en/publications/asymmetric-phospholipid-lipopolysaccharide-bilayers-a-gram-negati
Cyclic and linear monoterpenes in phospholipid membranes: Phase behavior, bilayer structure, and molecular dynamics. - Lund...Cyclic and linear monoterpenes in phospholipid membranes: Phase behavior, bilayer structure, and molecular dynamics. - Lund...
abstract = Monoterpenes are abundant in essential oil extracted from plants. These relatively small and hydrophobic molecules have shown many important biological fucntions, including antimicrobial activity and membrane penetration enhancement. The interaction between the monoterpenes and lipid bilayers is considered important to the understanding of the biological functions of monoterpenes. In this study we investigate the effect of cyclic and linear monoterpenes on the structure and dynamics of lipids in model membrane. We study the ternary system 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) - monoterpene - water as a model with a focus on dehydrated conditions. By combining complementary techniques, including differential scanning calorimetry (DSC), solid-state nuclear magnetic resonance (ss NMR) and small and wide angle X-ray scattering (SAXS and WAXS), bilayer structure, phase transitions and lipid molecular dynamics are investigated at different water contents. Monoterpenes cause ...
https://portal.research.lu.se/portal/en/publications/cyclic-and-linear-monoterpenes-in-phospholipid-membranes-phase-behavior-bilayer-structure-and-molecular-dynamics
Area on lipid bilayer occupied by phospholipi - Rat Rattus norvegicus - BNID 102781Area on lipid bilayer occupied by phospholipi - Rat Rattus norvegicus - BNID 102781
P.838 right column 3rd paragraph: The number of all phospholipid and cholesterol molecules per vesicle was calculated to be approximately 7000 and 5600, respectively, with hexosylceramides and gangliosides making only a relatively minor contribution (Table 2). Considering that a single phospholipid molecule occupies a space of approximately 65 Å^2 (0.65 nm^2) (primary source), 7000 phospholipids would build a planar bilayer of 4550 nm^2, i.e., 50% of the outer and inner surfaces of a vesicle possessing an outer diameter of 42 nm ...
https://bionumbers.hms.harvard.edu/bionumber.aspx?id=102781&ver=4&trm=Phospholipid&org=
Direct Measurement of the Mechanical Properties of Lipid Phases in Supported Bilayers - Inserm
Biological membranes define not only the cell boundaries but any compartment within the cell. To some extent, the functionality of membranes is related to the elastic properties of the lipid bilayer and the mechanical and hydrophobic matching with functional membrane proteins. Supported lipid bilayers (SLBs) are valid biomimetic systems for the study of membrane biophys-ical properties. Here, we acquired high-resolution topographic and quantitative mechanics data of phase-separated SLBs using a recent atomic force microscopy (AFM) imaging mode based on force measurements. This technique allows us to quantitatively map at high resolution the mechanical differences of lipid phases at different loading forces. We have applied this approach to evaluate the contribution of the underlying hard support in the determination of the elastic properties of SLBs and to determine the adequate indentation range for obtaining reliable elastic moduli values. At ~200 pN, elastic forces dominated the force-indentation
https://www.hal.inserm.fr/inserm-01363280
Noise measurements in bilayer lipid membranes during electroporation : Sussex Research OnlineNoise measurements in bilayer lipid membranes during electroporation : Sussex Research Online
A study of voltage fluctuations in bilayer lipid membranes during electroporation and under current-clamp conditions is presented. Qualitative considerations based on the electroporation theory are used in order to explain the phenomenon on long time scale. Indeed, the current-clamp condition induces a feedback mechanism on the pore formation and therefore on the macroscopic conductance. Voltage fluctuations can thus be recorded. These fluctuations are nonstationary long-living and have a flicker power spectrum over nearly four decades of frequency between about 10-2 and 102Hz. The study of the fluctuations in the time domain has been performed by introducing an electrical model of the system formed by the membrane and the circuit under current-clamp configuration. The analysis of the time series gives a characteristic time of 100ms for the circuitry response to the fragments of electroporation signals with characteristic times faster than 100ms. During electroporation, the response to an ...
http://sro.sussex.ac.uk/id/eprint/50300/
PLGA nanocapsules coated with phosphatidylcholine bilayerPLGA nanocapsules coated with phosphatidylcholine bilayer
Page contains details about PLGA nanocapsules coated with phosphatidylcholine bilayer . It has composition images, properties, Characterization methods, synthesis, applications and reference articles : nano.nature.com
http://nano.nature.com/nano/GR-M2546249
Isolation and characterization of a family of porin proteins from Helicobacter pylori. | Infection and ImmunityIsolation and characterization of a family of porin proteins from Helicobacter pylori. | Infection and Immunity
Two-dimensional gel electrophoresis was used to identify heat-modifiable outer membrane proteins, which were candidates for porins, from Helicobacter pylori membrane preparations. Four such proteins with apparent molecular masses of 48, 49, 50, and 67 kDa were isolated. The four proteins copurified together after selective detergent solubilizations followed by anion-exchange chromatography, and each protein was ultimately purified to homogeneity by gel purification. These proteins were then tested for pore-forming ability with a planar lipid bilayer model membrane system. All four proteins appeared to be present as monomers, and they formed pores with low single-channel conductances in 1.0 M KCl of 0.36, 0.36, 0.30, and 0.25 nS, respectively, for the 48-, 49-, 50-, and 67-kDa proteins which we propose to designate HopA, HopB, HopC, and HopD. N-terminal amino acid sequence analyses showed a high degree of homology among all four proteins, and it appears that these proteins constitute a family of ...
https://iai.asm.org/content/63/4/1567?ijkey=81438b5017c90a675b937389bdf61596041ec0da&keytype2=tf_ipsecsha
Dynamical Simulations of Virus Wrapping and Budding - Department of Theoretical Condensed Matter PhysicsDynamical Simulations of Virus Wrapping and Budding - Department of Theoretical Condensed Matter Physics
We explore this process through modeling the wrapping of a spherical particle by a model bilayer membrane, using coarse-grained molecular dynamics simulations and a theoretical elastic model. Specifically, we study the kinetics and morphologies of wrapping as a function of the relevant system parameters, including the particle radius, the strength of the membrane-particle interaction, and the membrane bending rigidity. The theoretical model predicts a phase diagram as a function of the system parameters, which is compared to results of the dynamics simulations ...
https://dep.ftmc.uam.es/dynamical-simulations-of-virus-wrapping-and-budding/
Softening of membrane bilayers by detergents elucidated by deuterium NMR spectroscopy - Fingerprint - University of Arizona
Dive into the research topics of Softening of membrane bilayers by detergents elucidated by deuterium NMR spectroscopy. Together they form a unique fingerprint. ...
https://arizona.pure.elsevier.com/en/publications/softening-of-membrane-bilayers-by-detergents-elucidated-by-deuter/fingerprints/
Faculty Collaboration Database - Physical properties of lipid bilayer membranes: relevance to membrane biological functions. ...Faculty Collaboration Database - Physical properties of lipid bilayer membranes: relevance to membrane biological functions. ...
Over the last 25 years one of us (WKS) has been investigating physical properties of lipid bilayer membranes. In 1991 a group led by WKS was organized into the Laboratory of Structure and Dynamics of Biological Membranes, the effective member of which is AW. Using mainly the electron paramagnetic resonance (EPR) spin-labeling method, we obtained unexpected results, which are significant for the better understanding of the functioning of biological membranes. We have developed a new pulse EPR spin-labeling method for the detection of membrane domains and evaluation of lipid exchange rates. This review will be focused on our main results which can be summarized as follows: (1) Unsaturation of alkyl chains greatly reduces the ordering and rigidifying effects of cholesterol although the unsaturation alone gives only minor fluidizing effects, as observed by order and reorientational motion, and rather significant rigidifying effects, as observed by translational motion of probe molecules; (2) ...
https://fcd.mcw.edu/?search/showPublication/id/30396
OPUS 4 | SearchOPUS 4 | Search
The interaction between lipid bilayers in water has been intensively studied over the last decades. Osmotic stress was applied to evaluate the forces between two approaching lipid bilayers in aqueous solution. The force-distance relation between lipid mono- or bilayers deposited on mica sheets using a surface force apparatus (SFA) was also measured. Lipid stabilised foam films offer another possibility to study the interactions between lipid monolayers. These films can be prepared comparatively easy with very good reproducibility. Foam films consist usually of two adsorbed surfactant monolayers separated by a layer of the aqueous solution from which the film is created. Their thickness can be conveniently measured using microinterferometric techniques. Studies with foam films deliver valuable information on the interactions between lipid membranes and especially their stability and permeability. Presenting inverse black lipid membrane (BLM) foam films supply information about the properties of ...
https://publikationen.reutlingen-university.de/solrsearch/index/search/searchtype/authorsearch/author/%22Krastev%2C+Rumen%22/start/0/rows/50/sortfield/title/sortorder/asc/facetNumber_publisher_name_facet/all
OPUS 4 | SearchOPUS 4 | Search
The interaction between lipid bilayers in water has been intensively studied over the last decades. Osmotic stress was applied to evaluate the forces between two approaching lipid bilayers in aqueous solution. The force-distance relation between lipid mono- or bilayers deposited on mica sheets using a surface force apparatus (SFA) was also measured. Lipid stabilised foam films offer another possibility to study the interactions between lipid monolayers. These films can be prepared comparatively easy with very good reproducibility. Foam films consist usually of two adsorbed surfactant monolayers separated by a layer of the aqueous solution from which the film is created. Their thickness can be conveniently measured using microinterferometric techniques. Studies with foam films deliver valuable information on the interactions between lipid membranes and especially their stability and permeability. Presenting inverse black lipid membrane (BLM) foam films supply information about the properties of ...
https://publikationen.reutlingen-university.de/solrsearch/index/search/searchtype/authorsearch/author/%22Krastev%2C+Rumen%22/start/0/rows/20/sortfield/title/sortorder/asc
Toward Atomistic Resolution Structure of Phosphatidylcholine Headgroup and Glycerol Backbone at Different Ambient Conditions -...Toward Atomistic Resolution Structure of Phosphatidylcholine Headgroup and Glycerol Backbone at Different Ambient Conditions -...
Phospholipids are essential building blocks of biological membranes. Despite a vast amount of very accurate experimental data, the atomistic resolution structures sampled by the glycerol backbone and choline headgroup in phoshatidylcholine bilayers are not known. Atomistic resolution molecular dynamics simulations have the potential to resolve the structures, and to give an arrestingly intuitive interpretation of the experimental data, but only if the simulations reproduce the data within experimental accuracy. In the present work, we simulated phosphatidylcholine (PC) lipid bilayers with 13 different atomistic models, and compared simulations with NMR experiments in terms of the highly structurally sensitive C-H bond vector order parameters. Focusing on the glycerol backbone and choline headgroups, we showed that the order parameter comparison can be used to judge the atomistic resolution structural accuracy of the models. Accurate models, in turn, allow molecular dynamics simulations to be used as an
https://hal-univ-lyon1.archives-ouvertes.fr/hal-02308166
PhD Theses • Numerical Analysis of Partial Differential Equations • Department of Mathematics and Computer SciencePhD Theses • Numerical Analysis of Partial Differential Equations • Department of Mathematics and Computer Science
Discrete-continuous hybrid models are a popular means for describing elastic membrane-mediated particle interactions in and on lipid bilayers. Here, the continuous part is usually given by an approximation of the lipid membrane by an infinitely thin and sufficiently smooth hypersurface, whose elastic energy is determined by a Canham-Helfrich type functional. The discrete component results from modeling non-membrane particles as rigid discrete entities, which, depending on their configuration, induce local constraints on the membrane along the membrane-particle interfaces. In this context, the interaction potential describes the optimal elastic energy of such hybrid systems with a fixed particle configuration. Correspondingly, the energy minimization principle yields that stationary particle configurations are given by the local minima of the interaction potential. The main goal of this work is the proof of differentiability of the interaction potential for a selected class of models. This is ...
https://www.mi.fu-berlin.de/en/math/groups/ag-numerik/theses_neu/index.html
PHOTOTOXICITY - LIGHT IS PAINFULLY BLUEPHOTOTOXICITY - LIGHT IS PAINFULLY BLUE
Abstract The capsaicin and mustard oil receptors TRPV1 and TRPA1, respectively, are highly expressed in polymodal nociceptors, ubiquitous thin nerve fibers that can evoke pain and induce neurogenic inflammation by neuropeptide secretion. Reversible oxidation of intracellular cysteine residues of these channel proteins causes activation and sensitization to adequate stimuli. The ion channel activity can be assessed in cultured sensory neurons, transfected cell lines, and in artificial lipid bilayers, using patch-clamp recording, calcium microfluorimetry, and indirectly by single-fiber recording and enzyme immunoassay measurement of stimulated neuropeptide (CGRP) release from isolated organ preparations. Strikingly, we found that ordinary blue light (405 nm) activates human TRPA1 and evokes pain in white human skin. This results from the ubiquitous presence of the heme precursor protoporphyrin IX (Pp IX) that acts as a chromophore to produce singlet oxygen under illumination. The ensuing ...
https://2018.cmos.org.tr/schedule/phototoxicity-light-is-painfully-blue/
2010.13237] Surface Energy and Separation Mechanics of Droplet Interface Phospholipid Bilayers2010.13237] Surface Energy and Separation Mechanics of Droplet Interface Phospholipid Bilayers
Abstract: Droplet interface bilayers are a convenient model system to study the physio-chemical properties of phospholipid bilayers, the major component of the cell membrane. The mechanical response of these bilayers to various external mechanical stimuli is an active area of research due to implications for cellular viability and development of artificial cells. In this manuscript we characterize the separation mechanics of droplet interface bilayers under step strain using a combination of experiments and numerical modeling. Initially, we show that the bilayer surface energy can be obtained using principles of energy conservation. Subsequently, we subject the system to a step strain by separating the drops in a step wise manner, and track the evolution of the bilayer contact angle and radius. The relaxation time of the bilayer contact angle and radius, along with the decay magnitude of the bilayer radius were observed to increase with each separation step. By analyzing the forces acting on the ...
https://export.arxiv.org/abs/2010.13237
Non-vesicular transfer of membrane proteins from nanoparticles to lipid bilayers | JGPNon-vesicular transfer of membrane proteins from nanoparticles to lipid bilayers | JGP
The study of membrane proteins (MPs) remains a major challenge in protein biochemistry mainly because of problems of protein aggregation and thermal instability in nonnative preparations of MPs in detergents, or native-like but insoluble preparations in liposomes. As a result, nonconventional surfactants with properties intermediate to lipids and detergents are becoming increasingly popular as alternative platforms for MPs (Bayburt and Sligar, 2002; Boldog et al., 2006; Park et al., 2007; Dalal et al., 2009; Popot, 2010). Discoidal lipoproteins, which include reconstituted high-density lipoprotein particles, nanodiscs, and nanoscale apolipoprotein-bound bilayers (NABBs), constitute a type of nonconventional platform that has enabled novel assays on MPs sequestered in a well-defined, soluble native-like lipid environment, such as single-particle imaging, surface plasmon resonance, nuclear magnetic resonance, and surface-enhanced infrared absorption spectroscopy (Banerjee et al., 2008; Das et al., ...
http://jgp.rupress.org/content/137/2/217
Molecular dynamics simulations of phospholipid bilayers under deformat by Anh TN VoMolecular dynamics simulations of phospholipid bilayers under deformat by Anh TN Vo
Model of nanoscale deformation mechanisms of cellular structures could render different results depending on the molecular dynamics (MD) simulator chosen. Also, the comparison of different MD simulators is typically an intricate task, requiring all configurations be converted appropriately with available parameter choices. This study aims to perform and compare MD simulations between two MD programs (GROMACS and LAMMPS), in which a phospholipid bilayer is deformed under different strain states. The two systems produced similar deformation behaviors and strain state effect on bilayer failure. However, GROMACS produced more pores at lower strains, lower stress, and higher damage values. Multiple setting options and algorithm variations have been considered as possible explanations for the differences. Overall, the study aids in the cross-check of parameter settings and simulation results in MD research, particularly on the mechanical damage of bilayer membranes. Besides, based on that, GROMACS and LAMMPS
https://scholarsjunction.msstate.edu/td/3187/
Diamond Publications - Search Results
Abstract: The activity of antimicrobial peptides stems from their interaction with bacterial membranes, which are disrupted according to a number of proposed mechanisms. Here, we investigate the interaction of a model antimicrobial peptide that contains a single arginine residue with vesicles containing model lipid membranes. The surfactant-like peptide Ala6-Arg (A6R) is studied in the form where both termini are capped (CONH-A6R-NH2, capA6R) or uncapped (NH2-A6R-OH, A6R). Lipid membranes are selected to correspond to model anionic membranes (POPE/POPG) resembling those in bacteria or model zwitterionic membranes (POPC/DOPC) similar to those found in mammalian cells. Viable antimicrobial agents should show activity against anionic membranes but not zwitterionic membranes. We find, using small-angle X-ray scattering (SAXS) and cryogenic-TEM (transmission electron microscopy) that, uniquely, capA6R causes structuring of anionic membranes due to the incorporation of the peptide in the lipid bilayer ...
https://publications.diamond.ac.uk/pubman/searchpublicationsadvanced?advancedsearch=1&titleOfJournal=Biomacromolecules&publicationStates%5B4%5D.selected=true
Macromolecular assemblyMacromolecular assembly
Experimental system, dioleoylphosphatidylcholine bilayers. The hydrophobic hydrocarbon region of the lipid is ~30 Å (3.0 nm) as ... "Structure of Fluid Lipid Bilayers". Blanco.biomol.uci.edu. 2009-11-10. Retrieved 2019-10-09. ... and of proteins within lipid bilayers. During assembly of the bacteriophage (phage) T4 virion, the morphogenetic proteins ... Protein-lipid complexes: lipoprotein. The biomacromolecular complexes are studied structurally by X-ray crystallography, NMR ...
https://en.wikipedia.org/wiki/Macromolecular_assembly
BiosynthesisBiosynthesis
2001). Lipid bilayers : structure and interactions ; with 6 tables. Berlin [u.a.]: Springer. ISBN 978-3540675556. Stryer, ... In turn, phospholipids and cholesterol interact noncovalently in order to form the lipid bilayer. This reaction may be depicted ... Biology portal Technology portal Lipids Phospholipid bilayer Nucleotides DNA DNA replication Proteinogenic amino acid Codon ... which in turn incorporate noncovalent interactions to form the lipid bilayer. Fatty acid chains are found in two major ...
https://en.wikipedia.org/wiki/Biosynthesis
WoodWood
Ionophores in Planar Lipid Bilayers". Cell physiology sourcebook: essentials of membrane biophysics (Fourth ed.). London, UK. ...
https://en.wikipedia.org/wiki/Wood
Hydrodynamic trappingHydrodynamic trapping
This allows particles protruding from the lipid bilayer to be trapped and studied. Hydrodynamic trapping can be used on a more ... Hydrodynamic trapping can also be used to trap and study molecules in lipid bilayers. This is done using hydrodynamic drag ... Hydrodynamic trapping of molecules in lipid bilayers. PNAS 2012 109 (26) 10328-10333. Michael Kühn, Helge Stanjek, Stefan ... are created by a fluid flow through a very small cone shaped pipet located about one micrometer away from the lipid bilayer. ...
https://en.wikipedia.org/wiki/Hydrodynamic_trapping
Robert Charles HiderRobert Charles Hider
The structure of melittin in lipid bilayers. Biochim. Biophys. Acta., 1979; 555, 371-373. Dufton MJ and Hider RC. Snake toxin ... The interaction of bee melittin with lipid bilayer membranes. Biochim. Biophys. Acta., 1978; 510, 75-86. Drake AF and Hider RC ... The composition of black lipid membranes formed from egg-yolk lecithin, cholesterol and n-decane. Biochimica Biophysica Acta., ... The effect of synthetic polymers on the electrical and permeability properties of lipid membranes. Biochim. Biophys. Acta., ...
https://en.wikipedia.org/wiki/Robert_Charles_Hider
WALP peptideWALP peptide
... farther from the interior of the lipid bilayer, in order to maintain their energetically favorable interaction with water. This ... "Hydrophobic Mismatch between Helices and Lipid Bilayers". Biophysical Journal. Biophysical Society. 84 (1): 379-385. Bibcode: ... When hydrophobic mismatch occurs, WALPs are known to tilt in the bilayer. The extent of this tilt is affected up to a certain ... point by an entropy contribution that arises from the helix's presence in the bilayer and then by more specific helix-lipid ...
https://en.wikipedia.org/wiki/WALP_peptide
Calcium-induced calcium releaseCalcium-induced calcium release
Planar Lipid Bilayers (BLMs) and Their Applications. Vol. 7. Elsevier. pp. 723-734. doi:10.1016/s0927-5193(03)80050-5. ISBN ... Koulen P (January 2003). "Chapter 26 - Using bilayer lipid membranes to investigate the pharmacology of intracellular calcium ...
https://en.wikipedia.org/wiki/Calcium-induced_calcium_release
Pressure perturbation calorimetryPressure perturbation calorimetry
Heerklotz, Heiko; Seelig, Joachim (2002-03-01). "Application of pressure perturbation calorimetry to lipid bilayers". ...
https://en.wikipedia.org/wiki/Pressure_perturbation_calorimetry
Susan DanielSusan Daniel
This achievement inspired Daniel to use the solid-supported lipid bilayers to separate membrane-bound species via ... Specifically, Daniel worked on solid-supported lipid bilayers. She showed that an artificial glycocalyx-like nanostructure ... She is interested in the role of membrane lipids in biological interactions, with a focus on how viruses interact with cell ... Cell membranes contain a variety of proteins and biomolecules, which are held within a matrix of lipid phases. Daniel believes ...
https://en.wikipedia.org/wiki/Susan_Daniel
DNA nanotechnologyDNA nanotechnology
DNA ion channels: Burns JR, Göpfrich K, Wood JW, Thacker VV, Stulz E, Keyser UF, Howorka S (November 2013). "Lipid-bilayer- ... DNA ion channels: Burns JR, Stulz E, Howorka S (June 2013). "Self-assembled DNA nanopores that span lipid bilayers". Nano ... on the DNA-lipid interface as no central channel lumen is present in the design that lets ions pass across the lipid bilayer. ... then demonstrated that such a DNA-induced toroidal pore can facilitate rapid lipid flip-flop between the lipid bilayer leaflets ...
https://en.wikipedia.org/wiki/DNA_nanotechnology
Artificial antigen presenting cellsArtificial antigen presenting cells
In natural systems, the dynamic lipid bilayer is crucial for molecular interactions. Lipid bilayer-based particles with a fluid ... Researchers also used solid particles as a core for the lipid bilayer to increase the stability of the liposomes. These are ... Castellana ET, Cremer PS (November 2006). "Solid supported lipid bilayers: From biophysical studies to sensor design". Surface ... known as supported lipid bilayers (SLBs). For example, nanoporous silica cores. A variety of polymers have been added into aAPC ...
https://en.wikipedia.org/wiki/Artificial_antigen_presenting_cells
CarotenoidCarotenoid
Windrem, David A.; Plachy, William Z. (1980). "The diffusion-solubility of oxygen in lipid bilayers". Biochimica et Biophysica ... By protecting lipids from free-radical damage, which generate charged lipid peroxides and other oxidised derivatives, ... Lipids and Lipid Metabolism. 1345 (3): 293-305. doi:10.1016/S0005-2760(97)00005-2. PMID 9150249. Zigangirova, Naylia A.; ... Since molecular oxygen is also a hydrophobic molecule, lipids provide a more favorable environment for O2 solubility than in ...
https://en.wikipedia.org/wiki/Carotenoid
Bcl-2 familyBcl-2 family
Their ability to form oligomeric pores in artificial lipid bilayers has been documented but the physiological significance of ... The colicins similarly form pores in lipid bilayers. Structural homology therefore suggests that Bcl-2 family members that ... A direct interaction of Bcl-2 with bilayer-reconstituted purified VDAC was demonstrated, with Bcl-2 decreasing channel ...
https://en.wikipedia.org/wiki/Bcl-2_family
Extracellular fluidExtracellular fluid
Windrem, David A.; Plachy, William Z. (August 1980). "The diffusion-solubility of oxygen in lipid bilayers". Biochimica et ... Lipids and Lipid Metabolism. 1345 (3): 293-305. doi:10.1016/S0005-2760(97)00005-2. PMID 9150249. Pocock G, Richards CD (2006). ... Bačič, G.; Walczak, T.; Demsar, F.; Swartz, H. M. (October 1988). "Electron spin resonance imaging of tissues with lipid-rich ... However, hydrophobic molecular oxygen has very poor water solubility and prefers hydrophobic lipid crystalline structures. As a ...
https://en.wikipedia.org/wiki/Extracellular_fluid
DetergentDetergent
Lichtenberg D, Ahyayauch H, Goñi FM (2013). "The mechanism of detergent solubilization of lipid bilayers". Biophysical Journal ... Solubilization of cell membrane bilayers requires a detergent that can enter the inner membrane monolayer. Advancements in the ...
https://en.wikipedia.org/wiki/Detergent
GlucocerebrosidaseGlucocerebrosidase
Alattia JR, Shaw JE, Yip CM, Privé GG (October 2006). "Direct visualization of saposin remodelling of lipid bilayers". Journal ... The role of Saposin C is not known; however, it is shown to bind both the lysosomal membrane and the lipid moieties of GluCer, ... The two aliphatic chains of glucocerebroside may remain associated with the lysosomal bilayer or interact with the activating ... GCase requires the activating protein Saposin C as well as negatively charged lipids for maximal catalytic activity. ...
https://en.wikipedia.org/wiki/Glucocerebrosidase
Absorption (pharmacology)Absorption (pharmacology)
They are essentially lipid bilayers which form semipermeable membranes. Pure lipid bilayers are generally permeable only to ... Lipid-soluble drugs are absorbed more rapidly than water-soluble drugs. The gastrointestinal tract is lined with epithelial ... passively diffuse through the gastrointestinal tract because the epithelial cell membrane is made up of a phospholipid bilayer ...
https://en.wikipedia.org/wiki/Absorption_(pharmacology)
Rhomboid proteaseRhomboid protease
What is unique about intramembrane proteases is that their active sites are buried in the lipid bilayer of cell membranes, and ... The active site of rhomboid protease is protected laterally from the lipid bilayer by its six constituent transmembrane helices ... Lemberg MK, Freeman M (December 2007). "Cutting proteins within lipid bilayers: rhomboid structure and mechanism". Molecular ... can occur in the hydrophobic environment of a lipid bilayer: one of the central mysteries of intramembrane proteases. The ...
https://en.wikipedia.org/wiki/Rhomboid_protease
GlobosideGloboside
"Parvovirus B19 VLP recognizes globoside in supported lipid bilayers". Virology. 456-457: 364-369. doi:10.1016/j.virol.2014.04. ... "Update of the LIPID MAPS comprehensive classification system for lipids". Journal of Lipid Research. 50: S9-S14. doi:10.1194/ ... Globosides are a sub-class of the lipid class glycosphingolipid with three to nine sugar molecules as the side chain (or R ...
https://en.wikipedia.org/wiki/Globoside
DeuteriumDeuterium
... of hydrocarbon chains in lipid bilayers can be quantified using solid state deuterium NMR with deuterium-labelled lipid ... "On the flexibility of hydrocarbon chains in lipid bilayers". Journal of the American Chemical Society. 93 (20): 5017-22. doi: ... Deuterated polyunsaturated fatty acids, such as linoleic acid, slow down the chain reaction of lipid peroxidation that damage ... August 2012). "Small amounts of isotope-reinforced polyunsaturated fatty acids suppress lipid autoxidation". Free Radical ...
https://en.wikipedia.org/wiki/Deuterium
Oleg Vladimirovich KrasilnikovOleg Vladimirovich Krasilnikov
Lipid bilayer Transmembrane protein Patch clamp Pore-forming toxin Krasilnikov, Oleg Vladimirovich. Protein channels in the ... reconstituted in planar lipid bilayers (principally α-staphylotoxin because of its unique ability to recognize polymer ... "The ionic channels formed by cholera toxin in planar bilayer lipid membranes are entirely attributable to its B-subunit". ... "Protein channels in a lipid bilayer" from Moscow State University of the Russian Academy of Sciences (1983). Krasilnikov began ...
https://en.wikipedia.org/wiki/Oleg_Vladimirovich_Krasilnikov
GlycosomeGlycosome
The membrane is a lipid bilayer. The glycogen that is found within the glycosome is identical to glycogen found freely in the ... For parasites, ether-lipid synthesis is vital to be able to complete its life cycle, making the enzymes protected by the ... These enzymes are those associated with ether-lipid synthesis or the beta oxidation of certain fatty acids. Cells without ... These processes include glycolysis, purine salvage, beta oxidation of fatty acids, and ether lipid synthesis. The main function ...
https://en.wikipedia.org/wiki/Glycosome
SynaptobrevinSynaptobrevin
Bock JB, Scheller RH (October 1999). "SNARE proteins mediate lipid bilayer fusion". Proc. Natl. Acad. Sci. U.S.A. 96 (22): ...
https://en.wikipedia.org/wiki/Synaptobrevin
Hypochlorous acidHypochlorous acid
The polar chlorine disrupts lipid bilayers and could increase permeability. When chlorohydrin formation occurs in lipid ... "Modification of red cell membrane lipids by hypochlorous acid and haemolysis by preformed lipid chlorohydrins". Redox Report: ... Hypochlorous acid reacts with unsaturated bonds in lipids, but not saturated bonds, and the ClO− ion does not participate in ... Stoichiometry and NMR analysis". Chemistry and Physics of Lipids. 78 (1): 55-64. doi:10.1016/0009-3084(95)02484-Z. PMID 8521532 ...
https://en.wikipedia.org/wiki/Hypochlorous_acid
ChemiosmosisChemiosmosis
Lipid bilayers of biological membranes, however, are barriers for ions. This is why energy can be stored as a combination of ... They would release electrons across the lipid membrane by diffusion to ferricyanide within the vesicles and release protons ... Proton gradients are generated across lipid membranes by redox reactions coupled to meteoritic quinones". Scientific Reports. 9 ...
https://en.wikipedia.org/wiki/Chemiosmosis
CholesterolCholesterol
Haines TH (July 2001). "Do sterols reduce proton and sodium leaks through lipid bilayers?". Progress in Lipid Research. 40 (4 ... Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid ... Christie WW (2003). Lipid analysis: isolation, separation, identification, and structural analysis of lipids. Ayr, Scotland: ... The enzyme is palmitoylated causing the enzyme to traffic to cholesterol dependent lipid domains sometimes called "lipid rafts ...
https://en.wikipedia.org/wiki/Cholesterol
PhospholipidPhospholipid
... in a bilayer such as a cell membrane. Lipid bilayers occur when hydrophobic tails line up against one another, forming a ... They can form lipid bilayers because of their amphiphilic characteristic. In eukaryotes, cell membranes also contain another ... so proteins and lipid molecules are then free to diffuse laterally through the lipid matrix and migrate over the membrane. ... as through the study of lipid polymorphism it is now known that the behaviour of lipids under physiological (and other) ...
https://en.wikipedia.org/wiki/Phospholipid
GlycerophospholipidGlycerophospholipid
Their amphipathic nature drives the formation of the lipid bilayer structure of membranes. The cell membrane seen under the ... These are important components for the formation of lipid bilayers. Phosphatidylethanoamines, phosphatidylcholines, and other ... Phosphatidates Phosphatidates are lipids in which the first two carbon atoms of the glycerol are fatty acid esters, and the 3 ... In bacteria and procaryotes, the lipids consist of diesters commonly of C16 or C18 fatty acids. These acids are straight- ...
https://en.wikipedia.org/wiki/Glycerophospholipid
OSBPOSBP
"Osh4p exchanges sterols for phosphatidylinositol 4-phosphate between lipid bilayers". J. Cell Biol. 195 (6): 965-78. doi: ... and a C-terminal lipid transport domain (ORD). The PH domain binds the trans-Golgi membrane by contacting the lipid PI4P and ... OSBP is a lipid transfer protein that controls cholesterol/PI4P exchange at ER-Golgi membrane contact sites. 25- ... OSBP is the founding member of the ORP (OSBP-related proteins) family of lipid transfer proteins. Mammals have 16 different ...
https://en.wikipedia.org/wiki/OSBP
RNAi nanoparticles to target cancerRNAi nanoparticles to target cancer
Lipoplexes are liposome structures characterized by a bilayer lipid membrane. Lastly, micelles result from electrostatic ... These four major types of nanoparticles are all nonionic lipids. Nonionic lipids are safe, nontoxic and biocompatible. ... Lipid nanoparticles (LNPs) are being considered for delivering siRNA to silence AR. The most effective LNP to be found in vivo ... "Lipid nanoparticle siRNA systems for silencing the androgen receptor in human prostate cancer in vivo". International Journal ...
https://en.wikipedia.org/wiki/RNAi_nanoparticles_to_target_cancer
Halobacterium salinarumHalobacterium salinarum
The membrane consists of a single lipid bilayer surrounded by an S-layer. The S-layer is made of a cell-surface glycoprotein ...
https://en.wikipedia.org/wiki/Halobacterium_salinarum
ENTH domainENTH domain
The lipid ligand is coordinated by residues from surrounding alpha-helices and all three phosphates are multiply coordinated. ... binding to membranes facilitates their deformation by insertion of the N-terminal helix into the inner leaflet of the bilayer, ... epsin is able to recruit and promote clathrin polymerisation on a lipid monolayer, but may have additional roles in signalling ...
https://en.wikipedia.org/wiki/ENTH_domain
SulfolobusSulfolobus
In Sulfolobales, the ether-linked lipids are joined covalently across the "bilayer," making tetraethers. Technically, therefore ... All Archaea have lipids with ether links between the head group and side chains, making the lipids more resistant to heat and ... acidity than bacterial and eukaryotic ester-linked lipids. The Sulfolobales are known for unusual tetraether lipids. ... the tetraethers form a monolayer, not a bilayer. The tetraethers help Sulfolobus species survive extreme acid as well as high ...
https://en.wikipedia.org/wiki/Sulfolobus
ViroporinViroporin
"Structure and drug binding of the SARS-CoV-2 envelope protein transmembrane domain in lipid bilayers". Nature Structural & ... An alternative mechanism is illustrated by the SARS-CoV E protein, which forms a pore that integrates membrane lipids whose ... The molecular architecture of the pore, its degree of selectivity, the extent to which it incorporates lipids from the ...
https://en.wikipedia.org/wiki/Viroporin
Klaus SchultenKlaus Schulten
Heller, Helmut; Schaefer, Michael; Schulten, Klaus (August 1993). "Molecular dynamics simulation of a bilayer of 200 lipids in ... 16,000 lipids, and 101 proteins, the contents of a tiny sphere-shaped organelle occupying just one percent of the cell's total ...
https://en.wikipedia.org/wiki/Klaus_Schulten
Water vaporWater vapor
This technique can display protein molecules, organelle structures and lipid bilayers with very low degrees of distortion. ...
https://en.wikipedia.org/wiki/Water_vapor
Violaxanthin de-epoxidaseViolaxanthin de-epoxidase
... is regulated by membrane fluidity in model lipid bilayers". European Journal of Biochemistry. 269 (18): 4656-65. doi:10.1046/j. ... Lipid composition and substrate specificity". Archives of Biochemistry and Biophysics. 190 (2): 514-22. doi:10.1016/0003-9861( ... Latowski D, Akerlund HE, Strzałka K (April 2004). "Violaxanthin de-epoxidase, the xanthophyll cycle enzyme, requires lipid ...
https://en.wikipedia.org/wiki/Violaxanthin_de-epoxidase
Polyproline helixPolyproline helix
"Bilayer thickness determines the alignment of model polyproline helices in lipid membranes". Physical Chemistry Chemical ... The PPII helix is not common in transmembrane proteins, and this secondary structure does not traverse lipid membranes in ...
https://en.wikipedia.org/wiki/Polyproline_helix
AerolysinAerolysin
... and to outline a mechanism by which this assembly might insert into lipid bilayers to form ion channels. Howard SP, Garland WJ ...
https://en.wikipedia.org/wiki/Aerolysin
David W. DeamerDavid W. Deamer
Deamer, D.W.; Branton, D. (1967). "Fracture planes in an ice-bilayer model membrane system". Science. 158 (3801): 655-657. ... and in 1985 Deamer demonstrated that the Murchison carbonaceous meteorite contained lipid-like compounds that could assemble ...
https://en.wikipedia.org/wiki/David_W._Deamer
Howard A. StoneHoward A. Stone
He has also studied problems concerning the flow of lipid bilayers and monolayers, and has investigated the motions of ...
https://en.wikipedia.org/wiki/Howard_A._Stone
Index of biochemistry articlesIndex of biochemistry articles
... lipid - lipid anchored protein - lipid bilayer - lipoprotein - liquid - list of compounds - list of gene families - locus - ... It deals with the structure and function of cellular components such as proteins, carbohydrates, lipids, nucleic acids and ... phospholipid bilayer - phosphopeptide - phosphoprotein - phosphorus - phosphorylation - phosphoserine - phosphothreonine - ...
https://en.wikipedia.org/wiki/Index_of_biochemistry_articles
Bacterial outer membrane vesiclesBacterial outer membrane vesicles
Gram-negative bacteria have a double set of bilayers. An inner bilayer, the inner cell membrane, encloses the cytoplasm or ... Bacterial outer membrane vesicles (OMVs) are vesicles of lipids released from the outer membranes of Gram-negative bacteria. ... Surrounding this inner cell membrane there is a second bilayer called the bacterial outer membrane. The compartment or space ...
https://en.wikipedia.org/wiki/Bacterial_outer_membrane_vesicles
NanoneuroscienceNanoneuroscience
They are both lipid-soluble and nano-scale and thus are permitted through a fully functioning BBB. Additionally, lipids ... The bilayer that is formed allows the molecule to fully encapsulate any drug, protecting it while it is travelling through the ... and lipid solubility. Physicians hope to circumvent difficulties in accessing the central nervous system through viral gene ...
https://en.wikipedia.org/wiki/Nanoneuroscience
Viral envelopeViral envelope
The lipid bilayer envelope of these viruses is relatively sensitive to desiccation, heat, and amphiphiles such as soap and ... Numerous human pathogenic viruses in circulation are encased in lipid bilayers, and they infect their target cells by causing ... Enveloped viruses enter cells by joining a cellular membrane to their lipid bilayer membrane. Priming by proteolytic processing ... These proteins are believed to catalyze the same mechanism in both situations, resulting in the fusing of two bilayers. In ...
https://en.wikipedia.org/wiki/Viral_envelope
Biomolecular condensateBiomolecular condensate
... of the mammary gland Serum albumin and globulins Secreted lysozyme Typical organelles or endosomes enclosed by a lipid bilayer ... In addition, lipid droplets are surrounded by a lipid monolayer in the cytoplasm, or in milk, or in tears, so appear to fall ... The modern usage of 'micelle' refers strictly to lipids, but its original usage clearly extended to other types of biomolecule ... Finally, secreted LDL and HDL lipoprotein particles are also enclosed by a lipid monolayer. The formation of these structures ...
https://en.wikipedia.org/wiki/Biomolecular_condensate
Perivitellin-2Perivitellin-2
... subunit would disrupt lipid bilayers forming large pores and leading to cell death, therefore constituting a true pore-forming ... able to disrupt intestinal cells altering the plasma membrane conductance and to form large pores in artificial lipid bilayers ...
https://en.wikipedia.org/wiki/Perivitellin-2
HemeHeme
Due to its lipophilic properties, it impairs lipid bilayers in organelles such as mitochondria and nuclei. These properties of ... It catalyzes the oxidation and aggregation of protein, the formation of cytotoxic lipid peroxide via lipid peroxidation and ...
https://en.wikipedia.org/wiki/Heme
CUTL1CUTL1
... but instead contains a trans-membrane domain that allows it to insert into lipid bilayers. It has been localized to the Golgi ...
https://en.wikipedia.org/wiki/CUTL1
OrthohantavirusOrthohantavirus
The lipid bilayer of the viral envelope is about 5 nm thick and is embedded with viral surface proteins to which sugar residues ... By mass, the virion is greater than 50% protein, 20-30% lipid, and 2-7% carbohydrate. The density of the virions is 1.18 g/cm3 ...
https://en.wikipedia.org/wiki/Orthohantavirus
Alkaline phosphataseAlkaline phosphatase
It also seems to regulate lipid absorption and bicarbonate secretion in the duodenal mucosa, which regulates the surface pH. ... with the remainder of the compound make phosphorylated compounds very much immiscible in the nonpolar region of the bilayer. ...
https://en.wikipedia.org/wiki/Alkaline_phosphatase
Protein aggregationProtein aggregation
It is known that protein aggregates in vitro can destabilize artificial phospholipid bilayers, leading to permeabilization of ... Influx into Lipid Vesicles Induced by Protein Aggregates". Angew. Chem. Int. Ed. Engl. 56 (27): 7750-7754. doi:10.1002/anie. ...
https://en.wikipedia.org/wiki/Protein_aggregation
Liquid crystalLiquid crystal
Elastic continuum theory is an effective tool for modeling liquid crystal devices and lipid bilayers. Scientists and engineers ... These lipids vary in shape (see page on lipid polymorphism). The constituent molecules can inter-mingle easily, but tend not to ... Lipid molecules can flip from one side of the membrane to the other, this process being catalyzed by flippases and floppases ( ... Lyotropic liquid-crystalline phases are abundant in living systems, the study of which is referred to as lipid polymorphism. ...
https://en.wikipedia.org/wiki/Liquid_crystal
Single-walled carbon nanohornSingle-walled carbon nanohorn
... as vaccine development and targeted drug delivery by embedding a target protein or immunogenic protein into the lipid bilayer ... Assembling lipids around carbon nanohorns would confer this nanomaterial much broader applications such ...
https://en.wikipedia.org/wiki/Single-walled_carbon_nanohorn
Lipid bilayer fusionLipid bilayer fusion
... the bilayers are said to be hemifused. In hemifusion, the lipid constituents of the outer leaflet of the two bilayers can mix, ... In membrane biology, fusion is the process by which two initially distinct lipid bilayers merge their hydrophobic cores, ... enveloped viruses are those surrounded by a lipid bilayer; some others have only a protein coat). Broadly, there are two ... particularly in eukaryotes since the eukaryotic cell is extensively sub-divided by lipid bilayer membranes. Exocytosis, ...
https://en.wikipedia.org/wiki/Lipid_bilayer_fusion
DiIDiI
... as DiI is retained in the lipid bilayers). DiI is manufactured by Invitrogen, which has a series of long-chain lipophilic ... based on their vertical sinking into or floating up with respect to a lipid bilayer driven by electric field which changes ... that relies on an extensive lipid removal by detergent (SDS). FAST DiI (D-3899 oil, D-7756 solid crystals) has diunsaturated ...
https://en.wikipedia.org/wiki/DiI
Membrane lipidMembrane lipid
... lipid bilayer). The three major classes of membrane lipids are phospholipids, glycolipids, and cholesterol. Lipids are ... The bilayer formed by membrane lipids serves as a containment unit of a living cell. Membrane lipids also form a matrix in ... Non-bilayer forming lipid like monogalactosyl diglyceride (MGDG) predominates the bulk lipids in thylakoid membranes, which ... lipid bilayer' which keeps the watery interior of the cell separate from the watery exterior. The arrangements of lipids and ...
https://en.wikipedia.org/wiki/Membrane_lipid
Function-spacer-lipid Kode constructFunction-spacer-lipid Kode construct
The second surface coating will be through the formation of bilayers as the lipid tail is unable to react with the hydrophilic ... In this case the lipids will induce the formation of a bilayer, the surface of which will be hydrophilic. This hydrophilic ... The lipid of the FSL anchors it to lipid membranes and gives the FSL construct its amphiphatic nature which can cause it to ... The lipid tail is essential for enabling lipid membrane insertion and retention but also for giving the construct amphiphilic ...
https://en.wikipedia.org/wiki/Function-spacer-lipid_Kode_construct
2007.05784] Rheology of sliding leaflets in coarse-grained DSPC lipid bilayers
Abstract: Amphiphilic lipid bilayers modify the friction properties of the surfaces on top of which they are deposited. In ... Title:Rheology of sliding leaflets in coarse-grained DSPC lipid bilayers. Authors:Othmène Benazieb, Claire Loison, Fabrice ... In particular, we gain access to the transient viscoelastic response of a sheared bilayer. The bilayer mechanical response is ... lipid bilayer subject to longitudinal shear. The interleaflet friction coefficient is obtained from out-of-equilibrium pulling ...
https://aps.arxiv.org/abs/2007.05784
A high-throughput genetic screening protocol to measure lipid bilayer stress-induced unfolded protein response in Saccharomyces...A high-throughput genetic screening protocol to measure lipid bilayer stress-induced unfolded protein response in Saccharomyces...
... known as lipid bilayer stress (LBS). In turn, ER stress triggers the unfolded protein response (UPR) to restore ER homeostasis ... A high-throughput genetic screening protocol to measure lipid bilayer stress-induced unfolded protein response in Saccharomyces ... known as lipid bilayer stress (LBS). In turn, ER stress triggers the unfolded protein response (UPR) to restore ER homeostasis ...
https://pubmed.ncbi.nlm.nih.gov/34647040/
Pull It Up - Tether Formation on Peptide Containing Supported Lipid Bilayers - Physik von Makromolekülen
Pull It Up - Tether Formation on Peptide Containing Supported Lipid Bilayers. Björn Goldenbogen (HUB, Institute for Biology/ ... Rapid Aging of Bilayer Graphene Oxide 25.11.2022. * At Least 10-fold Higher Lubricity of Molecularly Thin D2O vs H2O Films at ... Tether Formation on Peptide Containing Supported Lipid Bilayers ... Tether Formation on Peptide Containing Supported Lipid Bilayers ...
https://www.physik.hu-berlin.de/de/pmm/forschungsseminar/pmmseminartermine/sem143
namd-l: Re: PBC in lipid bilayer: receptor vs. ligand
PBC in lipid bilayer: receptor vs. ligand" *Next in thread: Norman Geist: "AW: PBC in lipid bilayer: receptor vs. ligand" * ... PBC in lipid bilayer: receptor vs. ligand" *Next in thread: Norman Geist: "AW: PBC in lipid bilayer: receptor vs. ligand" * ... lipid bilayer gets shifted in the opposite direction with respect to the solvent bilayer and I dont understand why. ... Re: PBC in lipid bilayer: receptor vs. ligand. From: R. Charbel MAROUN (charbel.maroun_at_inserm.fr). Date: Mon Feb 01 2016 - ...
http://www.ks.uiuc.edu/Research/namd/mailing_list/namd-l.2016-2017/0107.html
Exceptions to lipid bilayer in cellsExceptions to lipid bilayer in cells
We got to talking about the lipid bilayer, which I assumed was present in all cells, and how the micelle forms spontaneously in ... Even extremophiles have a lipid bilayer, however on the wikipedia website it states that nearly all living things have cells ... Phylogenomic Study of Lipid Genes Involved in Microalgal Biofuel Production Candidate Gene Mining and Metabolic Pathway ... Many extremophile organisms from the Archaea group have lipid monolayers. Have a look at the two membrane structures on the ...
http://www.thescienceforum.com/biology/22588-exceptions-lipid-bilayer-cells.html
Daniel Liu, Heads and Tails: Molecular Imagination and the Lipid Bilayer, 1917-1941 - PhilPapersDaniel Liu, Heads and Tails: Molecular Imagination and the Lipid Bilayer, 1917-1941 - PhilPapers
Yet the image of the lipid bilayer, built out of lipids ... ... the lipid bilayer structure is nearly ubiquitous, taken for ... Yet the image of the lipid bilayer, built out of lipids with heads and tails, went from having obscure origins deep in colloid ... Today, the lipid bilayer structure is nearly ubiquitous, taken for granted in even the most rudimentary introductions to cell ... molecular biology cell biology lipid bilayer cell membrane molecular imagination colloid chemistry microscopy physical ...
https://philpapers.org/rec/LIUHAT
A synthetic enzyme built from DNA flips 107 lipids per second in biological membranes | Nature CommunicationsA synthetic enzyme built from DNA flips 107 lipids per second in biological membranes | Nature Communications
Here the authors design a DNA nanostructure that catalyzes the transport of lipids between bilayers at a rate three orders of ... The membrane insertion catalyzes spontaneous transport of lipid molecules between the bilayer leaflets, rapidly equilibrating ... Through a combination of microscopic simulations and fluorescence microscopy we find the lipid transport rate catalyzed by the ... DNA nanostructure exceeds 107 molecules per second, which is three orders of magnitude higher than the rate of lipid transport ...
https://www.nature.com/articles/s41467-018-04821-5?error=cookies_not_supported
2015 - Antibiotic translocation through porins studied in planar lipid bilayers using parallel platforms2015 - Antibiotic translocation through porins studied in planar lipid bilayers using parallel platforms
... Orbit 16, Port-a-Patch ... Here, the classical method is to reconstitute single porins into planar lipid bilayers to derive functional information from ... Bilayer recordings: Alamethicin single channel conductances. Recordings from a GUV prepared bilayer in 85 mM KCl at -140 mV. ...
https://www.nanion.de/en/products/port-a-patch/137-home/articles/992-2015-antibiotic-translocation-through-porins-studied-in-planar-lipid-bilayers-using-parallel-platforms.html
Subdiffusion and lateral diffusion coefficient of lipid atoms and molecules in phospholipid bilayers - McMaster Experts
... investigate the dynamics of selected lipid atoms and lipid molecules in a hydrated diyristoyl-phosphatidylcholine lipid bilayer ... Subdiffusion and lateral diffusion coefficient of lipid atoms and molecules in phospholipid bilayers Academic Article ... We also examine the implications of the presence of the subdiffusive dynamics of lipids on the self-intermediate scattering ... of lipid atoms and molecules exhibits three well-separated dynamical regions: (i) ballistic, with <[deltar(t)]2> approximately ...
https://experts.mcmaster.ca/display/publication228394
Effect of urea and tmao on lipid bilayersEffect of urea and tmao on lipid bilayers
Modification of Phospholipid Bilayers Induced by Sulfurated Naphthoquinones. J. Lipids, 2013, Article ID 592318.. 10.1155/2013/ ... 4] Valerio J, Lameiro HM; Funari SS, Moreno MJ, Eurico E.Temperature Effect on the Bilayer Stacking in Multilamellar Lipid ... 5] Silva T, Adao R, Nazmi K, Bolscher JGM, Funari SS, Uhrikova D, Bastos M. Structural diversity and mode of action on lipid ... 9] Tenchov B & Koynova R. Cubic phases in membrane lipids. Eur Biophys J (2012),41:841. 10.1007/s00249-012-0819-3. 22584384. ...
https://sciendo.com/es/article/10.1515/afpuc-2017-0003
Molecular Dynamics and EPR spectroscopy on lipid bilayers: new approaches to study biological membranes - University of...Molecular Dynamics and EPR spectroscopy on lipid bilayers: new approaches to study biological membranes - University of...
Molecular Dynamics and EPR spectroscopy on lipid bilayers: new approaches to study biological membranes. *Oganesyan, Vasily ( ... Direct prediction of EPR spectra from lipid bilayers: Understanding structure and dynamics in biological membranes. Catte, A., ...
https://research-portal.uea.ac.uk/en/projects/molecular-dynamics-and-epr-spectroscopy-on-lipid-bilayers-new-app
Interaction of diverse voltage sensor homologs with lipid bilayers revealed by self-assembly simulations. - Oxford Neuroscience
In cationic lipid bilayers lacking phosphate groups, VSs form fewer contacts with lipid headgroups. The S3-S4 paddle motifs ... leading to a characteristic local distortion of the lipid bilayer which decreases its thickness by ∼10 Å. This effect is ... We used molecular dynamics simulations to examine interactions with lipids of several VS homologs. VSs in intact channels in ... providing insights into the molecular basis of their stabilization in the membrane and how they are altered by lipid ...
https://www.neuroscience.ox.ac.uk/publications/124549
Dewetting induced lipid bilayer multicomponent scaffold for synthetic by Anjana Khanal"Dewetting induced lipid bilayer multicomponent scaffold for synthetic " by Anjana Khanal
Silica nanoparticles supported lipid bilayer shows long term stability due to presence of a solid silica core. ... this by producing double emulsions containing 1-8 inner water droplets and studied their dewetting phenomena to lipid bilayer ... Silica nanoparticles supported lipid bilayer shows long term stability due to presence of a solid silica core. ... Dewetting induced lipid bilayer multicomponent scaffold for synthetic cell vesicle and their stability ...
https://rdw.rowan.edu/etd/2872/
Infrared spectroscopic characterization of the interaction of lipid bilayers with phenol, salicylic acid and o-acetylsalicylic...Infrared spectroscopic characterization of the interaction of lipid bilayers with phenol, salicylic acid and o-acetylsalicylic...
Infrared spectroscopic characterization of the interaction of lipid bilayers with phenol, salicylic acid and o-acetylsalicylic ... Infrared spectroscopic characterization of the interaction of lipid bilayers with phenol, salicylic acid and o-acetylsalicylic ... Infrared spectroscopic characterization of the interaction of lipid bilayers with phenol, salicylic acid and o-acetylsalicylic ... Possible modes of interaction of these guest molecules with the lipid bilayers are discussed. ...
https://nrc-publications.canada.ca/eng/view/object/?id=cb713138-7bec-433e-aa45-0d7dcb45f03a
Average orientation of a fluoroaromatic molecule in lipid bilayers from DFT-informed NMR measurements of 1H-19F dipolar...
Average orientation of a fluoroaromatic molecule in lipid bilayers from DFT-informed NMR measurements of 1H-19F dipolar ... Understanding the structure, dynamics and orientation of fluoroaromatic molecules in lipid bilayers can provide useful insight ... rapidly rotating within a lipid bilayer. The 19F chemical shift tensor orientation in the molecular frame was calculated by ... bilayers to restrict the axis of molecular reorientation of FBTA in the bilayer to two possible orientations. This approach, ...
https://www.research.lancs.ac.uk/portal/en/publications/average-orientation-of-a-fluoroaromatic-molecule-in-lipid-bilayers-from-dftinformed-nmr-measurements-of1h19f-dipolar-couplings
Structural basis for substrate specificity and regulation of nucleotide sugar transporters in the lipid bilayer - WRAP: Warwick...Structural basis for substrate specificity and regulation of nucleotide sugar transporters in the lipid bilayer - WRAP: Warwick...
2019) Structural basis for substrate specificity and regulation of nucleotide sugar transporters in the lipid bilayer. Nature ... Structural basis for substrate specificity and regulation of nucleotide sugar transporters in the lipid bilayer ... The structure of the yeast GDP-mannose transporter, Vrg4, revealed a requirement for short chain lipids and a marked difference ... Nucleotides , Glycosylation, Endoplasmic reticulum, Molecular dynamics, Membrane lipids. Journal or Publication Title:. Nature ...
http://wrap.warwick.ac.uk/126479/
Françoise Van Bambeke | UCLouvainFrançoise Van Bambeke | UCLouvain
Passive diffusion of polymeric surfactants across lipid bilayers.. In: Journal of Controlled Release, Vol. 120, no. 1-2, p. 79- ... Modulation of the in vitro activity of lysosomal phospholipase A1 by membrane lipids. In: Chemistry and Physics of Lipids, Vol ... Piracetam inhibits the lipid-destabilising effect of the amyloid peptide Abeta C-terminal fragment. In: BBA - Biomembranes, Vol ... Interactions of oritavancin, a new semi-synthetic lipoglycopeptide, with lipids extracted from Staphylococcus aureus.. In: BBA ...
https://uclouvain.be/en/directories/francoise.vanbambeke
Structural Biochemistry/Lipids - Wikibooks, open books for an open worldStructural Biochemistry/Lipids - Wikibooks, open books for an open world
Lipid bilayers display elastic properties due to their fluid structures. The fluidity of the lipid bilayer is described by the ... The lipid bilayer is favored by phospholipids and glycolipids because the fatty acid tails on the lipids are too bulky to be ... Lipid Bilayers are a perfect example of how structure plays a role in function. The structure of the bilayer provides a ... 2. Membrane Lipids and Membrane Proteins[edit , edit source]. -Membrane Lipids: Three common membrane lipids: Phospholipids: ...
https://en.wikibooks.org/wiki/Structural_Biochemistry/Lipids
Thermal, dynamic and structural properties of drug AT[sub]1 antagonist olmesartan in lipid bilayers :: COBISS+Thermal, dynamic and structural properties of drug AT[sub]1 antagonist olmesartan in lipid bilayers :: COBISS+
Thus, lipid bilayers are expected to ... be actively involved and play acritical role in drug action. For this reason, the ... Olmesartan locates itself at the head-group region and upper segment of the lipid bilayers as 13C CP/MAS spectra show that its ... Opomba glede Thermal, dynamic and structural properties of drug AT[sub]1 antagonist olmesartan in lipid bilayers:. ... 13C CP/MAS spectra provided direct evidence for the incorporation ofolmesartan and cholesterol in lipid bilayers. Raman and X- ...
https://plus.cobiss.net/cobiss/si/sl/bib/4754202?lang=sl
A Solvent Free Lipid Bilayer Model Using Multiscale Coarse-graining | The Voth GroupA Solvent Free Lipid Bilayer Model Using Multiscale Coarse-graining | The Voth Group
A Solvent Free Lipid Bilayer Model Using Multiscale Coarse-graining. Title. A Solvent Free Lipid Bilayer Model Using Multiscale ...
https://vothgroup.uchicago.edu/publications/solvent-free-lipid-bilayer-model-using-multiscale-coarse-graining
ArboCat Virus: Vesicular Stomatitis, Alagoas serotype (VSAV)
surface projections, 6-10 nm; bilayer lipid membrane Nucleocapsid Dimensions, Symmetry. Morphogenesis. ... Lipid Solvent (ether - % used to test). After Treatment Titer. Control Titer. Lipid Solvent (chloroform). sensitive (1) After ... Lipid. 20-25% Carbohydrate. 3-15%; RNA = 0.7-5% Virion Polypeptides: Number. 5 Details. not published, probably similar to ...
https://wwwn.cdc.gov/arbocat/VirusDetails.aspx?ID=511&SID=4
Protein identification by nanopore peptide profiling | Nature CommunicationsProtein identification by nanopore peptide profiling | Nature Communications
The Langmuir-Blodgett method, as described by Maglia et al.23, was used to create planar lipid bilayers. Peptides and protein ... Planar lipid bilayer electrophysiological recordings. A 25 µm thick Teflon membrane (Goodfellow Cambridge Ltd.) containing an ... Baaken, G., Ankri, N., Schuler, A.-K., Rühe, J. & Behrends, J. C. Nanopore-based single-molecule mass spectrometry on a lipid ... and sphingomyelin were received from Avanti Polar Lipids. Ni-NTA beads were obtained from Qiagen. ...
https://www.nature.com/articles/s41467-021-26046-9?error=cookies_not_supported&code=d936bf42-18da-4dc2-9b6b-15de08eabea6
Amyloids of Alpha-Synuclein Affect the Structure and Dynamics of Supported Lipid Bilayers<...
Amyloids of Alpha-Synuclein Affect the Structure and Dynamics of Supported Lipid Bilayers. / Iyer, A.S.; Petersen, N.O.; ... Amyloids of Alpha-Synuclein Affect the Structure and Dynamics of Supported Lipid Bilayers. In: Biophysical journal. 2014 ; Vol ... Dive into the research topics of Amyloids of Alpha-Synuclein Affect the Structure and Dynamics of Supported Lipid Bilayers. ... We have systematically analyzed the distribution and self-assembly of monomeric αS on supported lipid bilayers. We observe that ...
https://research.utwente.nl/en/publications/amyloids-of-alpha-synuclein-affect-the-structure-and-dynamics-of-
Gentle Imaging of Lipid Bilayers with Encased Cantilevers | Scuba Probe TechnologiesGentle Imaging of Lipid Bilayers with Encased Cantilevers | Scuba Probe Technologies
... results in a bilayer height of 5.4 nm. In contrast, (b) encased cantilevers reveal a bilayer thickness of 6.5 nm. This bilayer ... Lipid bilayers readily deform under the force applied by the AFM tip. Scuba Probes encased cantilevers offer gentler imaging ... conditions as shown here imaging supported DPPC lipid bilayers (L-αdipalmitoyl-phosphatidylcholine) that were prepared using a ...
https://scubaprobe.com/2017/11/10/gentle-imaging-of-lipid-bilayers-with-encased-cantilevers/
Immobilizing BK-channels in artificial lipid bilayers using annexin v<...
Takeuchi, Y., Aoki, T., Yanagida, T., & Ide, T. (2007). Immobilizing BK-channels in artificial lipid bilayers using annexin v. ... Takeuchi, Y, Aoki, T, Yanagida, T & Ide, T 2007, Immobilizing BK-channels in artificial lipid bilayers using annexin v, e- ... Immobilizing BK-channels in artificial lipid bilayers using annexin v. In: e-Journal of Surface Science and Nanotechnology. ... Immobilizing BK-channels in artificial lipid bilayers using annexin v. e-Journal of Surface Science and Nanotechnology. 2007 ...
https://okayama.pure.elsevier.com/en/publications/immobilizing-bk-channels-in-artificial-lipid-bilayers-using-annex
The changes of capacitance relaxation of bilayer lipid membranes induced by chlorpromazine<...
The changes of capacitance relaxation of bilayer lipid membranes induced by chlorpromazine. In: Pharmazie. 2000 ; Vol. 55, No. ... The changes of capacitance relaxation of bilayer lipid membranes induced by chlorpromazine. Pharmazie. 2000 Jan 1;55(7):546-547 ... The changes of capacitance relaxation of bilayer lipid membranes induced by chlorpromazine. / Hianik, Tibor; Fajkus, M.; Tarus ... title = "The changes of capacitance relaxation of bilayer lipid membranes induced by chlorpromazine", ...
https://utsouthwestern.pure.elsevier.com/en/publications/the-changes-of-capacitance-relaxation-of-bilayer-lipid-membranes-
Cholesterol modulates the Interaction of beta amyloid peptide with lipid bilayers<...
Cholesterol modulates the Interaction of beta amyloid peptide with lipid bilayers. Liming Qiu, Anthony Lewis, John Como, Mark ... Cholesterol modulates the Interaction of beta amyloid peptide with lipid bilayers. In: Biophysical Journal. 2009 ; pp. 4299- ... Cholesterol modulates the Interaction of beta amyloid peptide with lipid bilayers. / Qiu, Liming; Lewis, Anthony; Como, John et ... Dive into the research topics of Cholesterol modulates the Interaction of beta amyloid peptide with lipid bilayers. Together ...
https://scholars.ttu.edu/en/publications/cholesterol-modulates-the-interaction-of-beta-amyloid-peptide-wit-8
Coimbra Chemistry Centre (CQC)Coimbra Chemistry Centre (CQC)
This includes studies on lipid bilayers and on the interactions of lipids and amphiphilic molecules with membrane proteins. The ... The homeostasis of lipids is another area of interest, including the development of hypocholesterolemic pharmaceutical agents ...
https://www.uc.pt/en/fctuc/research/cqc-centro-de-quimica-de-coimbra/
hydrophillic surface of a lipid bilayer is like the surface of a pondhydrophillic surface of a lipid bilayer is like the surface of a pond
hydrophillic surface of a lipid bilayer is exlained to be like a the surface of a pond analysis simile ...
http://www.metamia.com/critique-hydrophillic-surface-of-a-lipid-bilayer-like-the-surface-of-a-pond-4944
Image Library | CDC Online Newsroom | CDCImage Library | CDC Online Newsroom | CDC
Both types of proteinaceous studs are embedded in the particle envelopes lipid bilayer. ...
https://www.cdc.gov/media/subtopic/images.htm
MoleculesProteinsPlanarFingerprintSupported bilayer lipid membranesPeptide with lipid bilayersPeptidesElectron microscopyMonolayersInteractionCoarse-grainedPhospholipid bilayersNanoparticlesSpectraMoleculeDPPCPhospholipidsHydrophobicPhase SeparationNearly ubiquitousBiological membranesAcyl chains2018SolventVesiclesMolecular DynamicsDOPCDynamicsAmphiphilicGPCRsChloroformAtomisticReceptorFunctionalTransportersParticle2019ChannelsArchaeaProteinMetabolismDropletsSelf-assembledStructureInteractCholesterolAmino-acidInteractionsPhenomenaSyntheticCell
Molecules16
  • This chapter examines how this schematic, strictly heuristic explanation of the idea of molecular orientation was developed within colloid physical chemistry, and how the image was transformed into a reflection of the reality and agency of lipid molecules in the biological microworld. (philpapers.org)
  • We use a long, all-atom molecular-dynamics (MD) simulation combined with theoretical modeling to investigate the dynamics of selected lipid atoms and lipid molecules in a hydrated diyristoyl-phosphatidylcholine lipid bilayer. (mcmaster.ca)
  • The membrane insertion catalyzes spontaneous transport of lipid molecules between the bilayer leaflets, rapidly equilibrating the lipid composition. (nature.com)
  • Through a combination of microscopic simulations and fluorescence microscopy we find the lipid transport rate catalyzed by the DNA nanostructure exceeds 10 7 molecules per second, which is three orders of magnitude higher than the rate of lipid transport catalyzed by biological enzymes. (nature.com)
  • The S3-S4 paddle motifs show persistent interactions of individual lipid molecules, influenced by the hairpin loop. (ox.ac.uk)
  • Possible modes of interaction of these guest molecules with the lipid bilayers are discussed. (canada.ca)
  • Understanding the structure, dynamics and orientation of fluoroaromatic molecules in lipid bilayers can provide useful insight into the effect of fluorine on their mode of action, and their interactions with membrane-embedded targets or efflux proteins. (lancs.ac.uk)
  • [1] Although lipids are amphiphatic molecules (containing both components of hydrophilic and hydrophobic regions within the molecule), lipids are generally hydrophobic due largely in part to their large proportion of hydrocarbons to polar regions (due to oxygen containing functional groups). (wikibooks.org)
  • Despite their differing functions, all biological membranes have a common general structure: each is a very thin film of lipid and protein molecules, held together mainly by noncovalent interactions. (nih.gov)
  • The lipid molecules are arranged as a continuous double layer about 5 nm thick ( Figure 10-1 ). (nih.gov)
  • This lipid bilayer provides the basic fluid structure of the membrane and serves as a relatively impermeable barrier to the passage of most water-soluble molecules. (nih.gov)
  • Protein molecules that span the lipid bilayer mediate nearly all of the other functions of the membrane, transporting specific molecules across it, for example, or catalyzing membrane-associated reactions, such as ATP synthesis. (nih.gov)
  • Lipid bilayers emerge by self-organization of amphiphilic molecules and are the essential component of membranes of living cells. (softmat.net)
  • Marco Werner, Jens-Uwe Sommer and Vladimir A. Baulin Soft Matter, 8, 11708-11716 (2012) Recent experimental studies indicate that polymeric structures with a well-adjusted balance of amphiphilic parts may translocate through self-assembled phospholipid bilayers and enhance the passive trans-membrane transport of smaller molecules. (softmat.net)
  • Such an interaction takes its origin at the lipid-water interface, but it propagates toward the entire lipid molecules and leads to a cooperative destabilization of the lipid acyl chains, that is, membrane disordering. (univ-brest.fr)
  • Layers of lipid molecules which are two molecules thick. (bvsalud.org)
Proteins13
  • The endoplasmic reticulum (ER) stress is defined by the accumulation of unfolded proteins at the ER and perturbation at the ER membrane, known as lipid bilayer stress (LBS). In turn, ER stress triggers the unfolded protein response (UPR) to restore ER homeostasis. (nih.gov)
  • Lipids can form bonds to proteins and carbohydrates forming lipoproteins and lipopolysaccharides. (wikibooks.org)
  • We observe that at protein/lipid ratios higher than 1:10, αS forms micrometer-sized clusters, leading to observable membrane defects and decrease in lateral diffusion of both lipids and proteins. (utwente.nl)
  • In the plasma membrane, some proteins serve as structural links that connect the cytoskeleton through the lipid bilayer to either the extracellular matrix or an adjacent cell, while others serve as receptors to detect and transduce chemical signals in the cell's environment. (nih.gov)
  • In this chapter we consider the structure and organization of the two main constituents of biological membranes-the lipids and the membrane proteins. (nih.gov)
  • These ratchets make use of asymmetrically patterned features and AC electric fields, and have been demonstrated to transport charged species such as lipids and transmembrane proteins between two reservoirs. (softmat.net)
  • Cell penetrating peptides, certain proteins, pore forming peptides can preferentially interact with lipid membranes and form different structures. (softmat.net)
  • OHM incorporation into the plasma membrane is proposed to dissociate the protein complex formed between SK3 and Orai1, a potassium and a calcium channel, respectively, and would lead to a modification in the lipid environment of both the proteins. (univ-brest.fr)
  • A number of specific proteins associate with LDs regulating organelle and lipid dynamics. (biorxiv.org)
  • Hereditary spherocytosis--defects in proteins that connect the membrane skeleton to the lipid bilayer. (medlineplus.gov)
  • Since GPCRs are integral membrane proteins, interaction of membrane lipids with them constitutes an important area of research in GPCR biology. (hindawi.com)
  • The various proteins and asymmetric lipid bilayers present in cell membranes form curvatures, resulting in structural transformations to generate vesicles. (elsevier.com)
  • VMD (Visual Molecular Dynamics) is designed for the visualization and analysis of biological systems such as proteins, nucleic acids, lipid bilayer assemblies, etc. (seikei.ac.jp)
Planar3
  • Here, the classical method is to reconstitute single porins into planar lipid bilayers to derive functional information from the observed channel conductance. (nanion.de)
  • Planar supported lipid bilayers (PSLB) presenting T cell receptor (TCR) ligands and ICAM-1 induce budding of extracellular microvesicles enriched in functional TCR, defined here as synaptic ectosomes (SE), from helper T cells. (elifesciences.org)
  • In: Advances in Planar Lipid Bilayers and Liposomes, Volume 3, S. 37 - 53 (Hg. (mpg.de)
Fingerprint1
  • Dive into the research topics of 'Immobilizing BK-channels in artificial lipid bilayers using annexin v'. Together they form a unique fingerprint. (elsevier.com)
Supported bilayer lipid membranes1
  • We present ratchets capable of directing the movement of charged components within supported bilayer lipid membranes. (softmat.net)
Peptide with lipid bilayers1
  • The study of the interaction of a model at-helical peptide with lipid bilayers and monolayers. (mpg.de)
Peptides2
  • 5] Silva T, Adao R, Nazmi K, Bolscher JGM, Funari SS, Uhrikova D, Bastos M. Structural diversity and mode of action on lipid membranes of three lactoferrin candidacidal peptides. (sciendo.com)
  • GPCRs regulate physiological responses to a variety of stimuli that include endogenous ligands such as biogenic amines, peptides, glycoproteins, lipids, nucleotides, Ca 2+ ions, and various exogenous ligands for sensory perception such as odorants, pheromones, and even photons. (hindawi.com)
Electron microscopy1
  • By electron microscopy, these lipid droplets are morphologically indistinguishable from those in wild-type cells. (biorxiv.org)
Monolayers2
  • Many extremophile organisms from the Archaea group have lipid monolayers. (thescienceforum.com)
  • Tethered bilayer lipid membranes based on monolayers of thiolipids mixed with a complementary dilution molecule. (mpg.de)
Interaction5
  • Interaction of diverse voltage sensor homologs with lipid bilayers revealed by self-assembly simulations. (ox.ac.uk)
  • The interaction of phenol (PHE), salicylic acid (SA) and o-acetylsalicylic acid (ASA) with bilayers of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) was investigated by infrared spectrometry. (canada.ca)
  • The underlying physical properties of lipids, water and their surface interaction led to the discovery of cell membrane. (who.int)
  • The selected contributions to the meeting can be published in the web themed issue " Interaction of nano-objects with lipid membranes " in Soft Matter. (itn-snal.net)
  • 2019. Interaction mechanism between the focused ultrasound and lipid membrane at the molecular level . (ibpc.fr)
Coarse-grained2
  • We investigate in this work the friction properties of a numerical coarse-grained model of DSPC (1,2-distearoyl-sn-glycero-3-phosphocholine) lipid bilayer subject to longitudinal shear. (arxiv.org)
  • MemProtMD simulation of Solution structure of HCV p7 tm2 in a lipid bilayer at both coarse-grained and atomistic respresentation, including both file download and analysis. (ox.ac.uk)
Phospholipid bilayers1
  • Modification of Phospholipid Bilayers Induced by Sulfurated Naphthoquinones. (sciendo.com)
Nanoparticles1
  • Silica nanoparticles supported lipid bilayer shows long term stability due to presence of a solid silica core. (rowan.edu)
Spectra4
  • It was then possible to analyse the line shapes of proton-coupled and proton-decoupled 19F spectra of FBTA in chain perdeuterated dimyristoylphosphatidylcholine (DMPC-d54) bilayers to restrict the axis of molecular reorientation of FBTA in the bilayer to two possible orientations. (lancs.ac.uk)
  • 13C CP/MAS spectra provided direct evidence for the incorporation ofolmesartan and cholesterol in lipid bilayers. (cobiss.net)
  • Olmesartan locates itself at the head-group region and upper segment of the lipid bilayers as 13C CP/MAS spectra show that its presence causes significant chemical shift changes mainly in the A ring of the steroidal part of cholesterol. (cobiss.net)
  • Raman and infrared spectra of fully hydrated bilayers of 1,2-dioleoyl phosphatidylcholine (DOPC) were measured at increasing hydrostatic pressures up to -37 kbar. (canada.ca)
Molecule3
  • Here we demonstrate that NMR measurements of 19F chemical shift anisotropy combined with 1H-19F dipolar coupling measurements together report on the average orientation of a lipophilic fluoroaromatic molecule, 4-(6-fluorobenzo[d]thiazol-2-yl)aniline (FBTA), rapidly rotating within a lipid bilayer. (lancs.ac.uk)
  • The liposomal technology forms a lipid bilayer over each molecule of retinol which makes it more stable, safe and ensures a targeted delivery to the skin. (fixderma.com)
  • To achieve this parallel interchain packing, the double bonds of the sn-1 and sn-2 chains of each molecule must be aligned at the same position with respect to the bilayer interface which is achieved by a rotation of the C-C bonds in the glycerol moiety in the head group. (canada.ca)
DPPC2
  • The influence of olmesartan on DPPC/cholesterol bilayers is less pronounced. (cobiss.net)
  • Scuba Probe's encased cantilevers offer gentler imaging conditions as shown here imaging supported DPPC lipid bilayers (L-αdipalmitoyl-phosphatidylcholine) that were prepared using a Langmuir-Blodgett trough, and transferred onto mica in an aqueous buffer. (scubaprobe.com)
Phospholipids5
  • A Theoretical Model for the Association Probabilities of Saturated Phospholipids From Two-Component Bilayer Lipid Membranes. (philpapers.org)
  • VSs in intact channels in the activated state are exposed to phospholipids, leading to a characteristic local distortion of the lipid bilayer which decreases its thickness by ∼10 Å. (ox.ac.uk)
  • In conclusion, our results suggest common interactions with phospholipids for various VS homologs, providing insights into the molecular basis of their stabilization in the membrane and how they are altered by lipid modification. (ox.ac.uk)
  • Lipids belong to a family of organic compounds which includes fats, vegetable oils, waxes, cholesterol , phospholipids, steroids, and fat-soluble vitamins (A, D, E, and K). They are formed by either or both carbanion-based condensation of thioesters and carbocation-based condensation of isoprene units. (wikibooks.org)
  • Lipid droplets are unique and nearly ubiquitous organelles that store neutral lipids in a hydrophobic core, surrounded by a monolayer of phospholipids. (biorxiv.org)
Hydrophobic3
  • The hydrophobic N-terminus of LRAT displays preferential interactions with retinyl esters in membranes and promotes the formation of large retinyl ester-containing lipid droplets in mammalian cells. (biorxiv.org)
  • LDs have a unique organellar architecture with a lipid monolayer surrounding a hydrophobic core that consists of neutral lipids. (biorxiv.org)
  • Remember in the last lecture we said the plasma membrane is a bilayer of lipids which forms a hydrophobic barrier around each cell in the body. (coursera.org)
Phase Separation1
  • Peter Olmsted ( Georgetown University) : "Asymmetry, Registration, Flip-Flop, and Phase Separation in Lipid Bilayers. (univ-paris-diderot.fr)
Nearly ubiquitous1
  • Today, the lipid bilayer structure is nearly ubiquitous, taken for granted in even the most rudimentary introductions to cell biology. (philpapers.org)
Biological membranes1
  • Bilayer systems are frequently studied as models of biological membranes. (bvsalud.org)
Acyl chains1
  • The extremely strong interchain interactions in the gel phase of DOPC are unique for this lipid with cis dimono-unsaturated acyl chains. (canada.ca)
20182
Solvent2
  • however, there were frames for which the lipid bilayer gets shifted in the 'opposite' direction with respect to the solvent bilayer and I don't understand why. (uiuc.edu)
  • When unwrapping protein and ligand, both get shifted with respect to lipids and solvent. (uiuc.edu)
Vesicles1
  • Funari SS, Moreno MJ, Eurico E.Temperature Effect on the Bilayer Stacking in Multilamellar Lipid Vesicles. (sciendo.com)
Molecular Dynamics3
  • We used molecular dynamics simulations to examine interactions with lipids of several VS homologs. (ox.ac.uk)
  • Molecular dynamics, combined with biochemical analysis, reveal a lipid mediated dimer interface and mechanism for coordinating structural rearrangements during transport. (warwick.ac.uk)
  • Impact of A2T and D23N Mutations on Tetrameric Aβ42 Barrel within a Dipalmitoylphosphatidylcholine Lipid Bilayer Membrane by Replica Exchange Molecular Dynamics. (ibpc.fr)
DOPC1
  • Our experimental results suggest that in the pressure-induced gel phase of DOPC the olefinic CH bonds are rotated out of the phase of the bent oleoyl chains and that the oleoyl chains of opposing bilayers bend towards opposite directions. (canada.ca)
Dynamics1
  • We also examine the implications of the presence of the subdiffusive dynamics of lipids on the self-intermediate scattering function and the incoherent dynamic structure factor measured in neutron-scattering experiments. (mcmaster.ca)
Amphiphilic1
  • Amphiphilic lipid bilayers modify the friction properties of the surfaces on top of which they are deposited. (arxiv.org)
GPCRs1
  • In this study, I will clarify the mechianism of the activation and regulation of GPCRs by structural elucidation of the dynamical equilibria of GPCRs under lipid bilayer environment, by using NMR. (go.jp)
Chloroform1
  • Therefore, Lipids are not soluble in water but are soluble in nonpolar solvents (ex: benzene and chloroform). (wikibooks.org)
Atomistic1
  • In silico study of levodopa in hydrated lipid bilayers at the atomistic level ( Grigorios Megariotis, Nikolaos Romanos, Aggelos Avramopoulos. (grnet.gr)
Receptor1
  • It is proposed that AT1 antagonists (ARBs) exert their biological action by inserting into the lipid membrane and then diffuse to the active site of AT1 receptor. (cobiss.net)
Functional4
  • There are eight categories of lipids defined by the LIPID MAPS Consortium, which classifies them by their chemically functional backbones. (wikibooks.org)
  • The novel system will directly reveal the functional mechanism for supramolecular assembly of ion channels in lipid bilayer. (go.jp)
  • Functional tethered bimolecular lipid membranes (tBLMs). (mpg.de)
  • Functional tethered lipid bilayer membranes. (mpg.de)
Transporters2
  • Together these results provide further insight into how SLC35 family transporters function within the secretory pathway and sheds light onto the role that membrane lipids play in regulating transport across the membrane. (warwick.ac.uk)
  • Our present study showed that the synbiotic product improved plasma total- and LDL-cholesterol levels by modifying the interconnected pathways of lipid transporters. (afpm.org.my)
Particle3
  • Here, we utilized bead supported lipid bilayers (BSLB) to capture SE from single immunological synapses (IS), determined SE composition by immunofluorescence flow cytometry and enriched SE for proteomic analysis by particle sorting. (elifesciences.org)
  • Both types of proteinaceous studs are embedded in the particle envelope's lipid bilayer. (cdc.gov)
  • Researchers at the National Cancer Institute's Laboratory of Molecular Biology have developed a novel, synthetic spore husk-encased lipid bilayer (SSHEL) particle that is uniquely suited for a variety of these functions. (cancer.gov)
20191
  • WRAP-structural-basis-substrate-specificity-nucleotide-sugar-lipid-Parker-2019.pdf - Published Version - Requires a PDF viewer. (warwick.ac.uk)
Channels4
  • These Cy5-labeled BK channels were incorporated into lipid bilayer membranes followed by single channel current measurements. (elsevier.com)
  • Immobilizing BK-channels in artificial lipid bilayers using annexin v . e-Journal of Surface Science and Nanotechnology , 5 , 1-5. (elsevier.com)
  • SK3 channels are abnormaly expressed in metastatic cells, and Ohmline (OHM), an ether lipid, has been shown to reduce the activity of SK3 channels and the migration capacity of cancer cells. (univ-brest.fr)
  • 2014. Volatile anesthetics inhibit sodium channels without altering bulk lipid bilayer properties. . (cornell.edu)
Archaea1
  • Archaea analogue thiolipids for tethered bilayer lipid membranes on ultrasmooth gold surfaces. (mpg.de)
Protein1
  • When doing that, protein, HME and lipid bi-layer get shifted in the plane of the membrane with respect to the water bi-layer. (uiuc.edu)
Metabolism1
  • However, LDs also play important roles in lipid metabolism and homeostasis. (biorxiv.org)
Droplets5
  • We demonstrate this by producing double emulsions containing 1-8 inner water droplets and studied their dewetting phenomena to lipid bilayer scaffold. (rowan.edu)
  • It is not known whether other classes of neutral lipids can form lipid droplets by themselves. (biorxiv.org)
  • Here we show that production of retinyl esters by lecithin:retinol acyl transferase (LRAT) in yeast cells, incapable of producing triacylglycerols and steryl esters, causes the formation of lipid droplets. (biorxiv.org)
  • In silico and in vitro experiments confirmed the propensity of retinyl esters to segregate from membranes and to form lipid droplets. (biorxiv.org)
  • Our combined data indicate that the molecular design of LRAT is optimally suited to allow the formation of characteristic large lipid droplets in retinyl ester-storing cells. (biorxiv.org)
Self-assembled2
  • Tethered bilayer lipid membranes self-assembled on mercury electrodes. (mpg.de)
  • Self-Assembled Tethered Bimolecular Lipid Membranes. (mpg.de)
Structure1
  • The structure of the yeast GDP-mannose transporter, Vrg4, revealed a requirement for short chain lipids and a marked difference in transport rate between the nucleotide sugar and nucleoside monophosphate, suggesting a complex network of regulatory elements control transport into these organelles. (warwick.ac.uk)
Interact2
  • These features allow the AMPs to interact with most microorganisms' lipid bilayer and eliminate them through membrane disruption or by translocating across the membrane and inhibiting cytosolic targets. (medscape.com)
  • These studies suggest that cholesterol can alter the conformation of IFITMs in membrane bilayers and directly interact with S -palmitoylated IFITMs in cells. (bvsalud.org)
Cholesterol3
  • Although, olmesartan and cholesterol are residing at the same region of the lipid bilayers, due to their different sizes, display distinct impacts on the bilayer's properties. (cobiss.net)
  • Use of deuterated lipids affords the demonstration of an OHM-induced membrane disordering, which is dose-dependent and increases with increasing amounts of cholesterol (CHOL). (univ-brest.fr)
  • The main lipids in the SC are ceramides, cholesterol, and free fatty acids (3). (cdc.gov)
Amino-acid1
  • Thus, citric acid cycle intermedi- ates are not used for adenosine triphosphate (ATP) production and are shuttled out of the mitochondria, providing precursors for nucleotide, amino acid, and lipid synthesis path- ways for the dividing cell [13]. (who.int)
Interactions1
  • Interactions of monomeric alpha-synuclein (αS) with lipid membranes have been suggested to play an important role in initiating aggregation of αS. (utwente.nl)
Phenomena1
  • Whereas in physical and colloid chemistry these images considered secondary to instrumental measurement and mathematical modeling of surface phenomena, in biology the manipulable image of the lipid on paper became an essential tool for the molecularization of the cell. (philpapers.org)
Synthetic2
  • Thus, development of biocompatible and easy to adapt synthetic analogues to repair and/or control lipid scrambling activity in cell membranes is of considerable medical interest. (nature.com)
  • Khanal, Anjana, "Dewetting induced lipid bilayer multicomponent scaffold for synthetic cell vesicle and their stability" (2021). (rowan.edu)
Cell2
  • Fluorine substitution may increase a molecule's lipophilicity, thereby enabling its diffusion across cell membranes to enhance bioavailability or to exert a direct physiological effect from within the lipid bilayer. (lancs.ac.uk)
  • One cellular feature of particular interest in biology is the plasma membrane, which has been shown to present varying degrees of lipid packing, or membrane order, depending on the function and morphology of the cell type. (bvsalud.org)
A synthetic enzyme built from DNA flips 107 lipids per second in biological membranes | Nature Communications
A synthetic enzyme built from DNA flips 107 lipids per second in biological membranes | Nature Communications (nature.com)
Protein identification by nanopore peptide profiling | Nature Communications
Protein identification by nanopore peptide profiling | Nature Communications (nature.com)
Image Library | CDC Online Newsroom | CDC
Image Library | CDC Online Newsroom | CDC (cdc.gov)
Composition and structure of synaptic ectosomes exporting antigen receptor linked to functional CD40 ligand from helper T cells...
Composition and structure of synaptic ectosomes exporting antigen receptor linked to functional CD40 ligand from helper T cells... (elifesciences.org)
High-resolution label-free 3D mapping of extracellular pH of single living cells | Nature Communications
High-resolution label-free 3D mapping of extracellular pH of single living cells | Nature Communications (nature.com)
2007.05784] Rheology of sliding leaflets in coarse-grained DSPC lipid bilayers
2007.05784] Rheology of sliding leaflets in coarse-grained DSPC lipid bilayers (aps.arxiv.org)
ANK1 gene: MedlinePlus Genetics
ANK1 gene: MedlinePlus Genetics (medlineplus.gov)
Hereditary spherocytosis: MedlinePlus Genetics
Hereditary spherocytosis: MedlinePlus Genetics (medlineplus.gov)
Membrane Structure - Molecular Biology of the Cell - NCBI Bookshelf
Membrane Structure - Molecular Biology of the Cell - NCBI Bookshelf (ncbi.nlm.nih.gov)
Physics - Routledge Handbooks Online
Physics - Routledge Handbooks Online (routledgehandbooks.com)
Coimbra Chemistry Centre (CQC)
Coimbra Chemistry Centre (CQC) (uc.pt)
Membrane tension controls the assembly of curvature-generating proteins | Nature Communications
Membrane tension controls the assembly of curvature-generating proteins | Nature Communications (nature.com)
Label as you fold: methyltransferase-assisted functionalization of DNA nanostructures - Nanoscale (RSC Publishing) DOI:10...
Label as you fold: methyltransferase-assisted functionalization of DNA nanostructures - Nanoscale (RSC Publishing) DOI:10... (pubs.rsc.org)
Amebiasis: Background, Pathophysiology, Etiology
Amebiasis: Background, Pathophysiology, Etiology (emedicine.medscape.com)
Type III ATP synthase is a symmetry-deviated dimer that induces membrane curvature through tetramerization | Nature...
Type III ATP synthase is a symmetry-deviated dimer that induces membrane curvature through tetramerization | Nature... (nature.com)
Western Equine Encephalitis: Background, Pathophysiology and Etiology, Epidemiology
Western Equine Encephalitis: Background, Pathophysiology and Etiology, Epidemiology (emedicine.medscape.com)
How they create such beautiful graphics? - DonationCoder.com
How they create such beautiful graphics? - DonationCoder.com (donationcoder.com)
Publikationen | Max-Planck-Institut für Polymerforschung
Publikationen | Max-Planck-Institut für Polymerforschung (mpip-mainz.mpg.de)
Laboratoire Matière et Systèmes Complexes - Séminaires 2018
Laboratoire Matière et Systèmes Complexes - Séminaires 2018 (msc.univ-paris-diderot.fr)
ETD Explore
ETD Explore (etda.libraries.psu.edu)
IJMS | Free Full-Text | Graphene Nanomaterials: Synthesis, Biocompatibility, and Cytotoxicity
IJMS | Free Full-Text | Graphene Nanomaterials: Synthesis, Biocompatibility, and Cytotoxicity (mdpi.com)
What Is a Detergent in Chemistry?
What Is a Detergent in Chemistry? (thoughtco.com)
60. [Glutamine & Alanine: The Urea Cycle II] | Biochemistry | Educator.com
60. [Glutamine & Alanine: The Urea Cycle II] | Biochemistry | Educator.com (educator.com)
A Parallelization Scheme for New DPD-B Thermostats
A Parallelization Scheme for New DPD-B Thermostats (hindawi.com)
Frontiers | Visualization of SNARE-Mediated Hemifusion between Giant Unilamellar Vesicles Arrested by Myricetin
Frontiers | Visualization of SNARE-Mediated Hemifusion between Giant Unilamellar Vesicles Arrested by Myricetin (frontiersin.org)
Theory of Soft Matter and Polymer Physics | Leibniz-Institut für Polymerforschung Dresden e. V.
Theory of Soft Matter and Polymer Physics | Leibniz-Institut für Polymerforschung Dresden e. V. (ipfdd.de)