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.
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.
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.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
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.
The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.
Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.
A colorless liquid with a sharp burning taste and slight odor. It is used as a local anesthetic and to reduce pain associated with LIDOCAINE injection. Also, it is used in the manufacture of other benzyl compounds, as a pharmaceutic aid, and in perfumery and flavoring.
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.
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.
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.
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.
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).
Salts and esters of the 12-carbon saturated monocarboxylic acid--lauric acid.
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.
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)
A naphthalene derivative with carcinogenic action.
A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.
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.
The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
Salts and esters of the 18-carbon saturated, monocarboxylic acid--stearic acid.
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.
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)
The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Alcohols derived from the aryl radical (C6H5CH2-) and defined by C6H5CHOH. The concept includes derivatives with any substituents on the benzene ring.
FATTY ACIDS in which the carbon chain contains one or more double or triple carbon-carbon bonds.
Minute projections of cell membranes which greatly increase the surface area of the cell.
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
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.
Peroxidase catalyzed oxidation of lipids using hydrogen peroxide as an electron acceptor.
Alkyl compounds containing a hydroxyl group. They are classified according to relation of the carbon atom: primary alcohols, R-CH2OH; secondary alcohols, R2-CHOH; tertiary alcohols, R3-COH. (From Grant & Hackh's Chemical Dictionary, 5th ed)
A darkly stained mat-like EXTRACELLULAR MATRIX (ECM) that separates cell layers, such as EPITHELIUM from ENDOTHELIUM or a layer of CONNECTIVE TISSUE. The ECM layer that supports an overlying EPITHELIUM or ENDOTHELIUM is called basal lamina. Basement membrane (BM) can be formed by the fusion of either two adjacent basal laminae or a basal lamina with an adjacent reticular lamina of connective tissue. BM, composed mainly of TYPE IV COLLAGEN; glycoprotein LAMININ; and PROTEOGLYCAN, provides barriers as well as channels between interacting cell layers.
Measurement of the intensity and quality of fluorescence.
An absence of warmth or heat or a temperature notably below an accustomed norm.
Isomeric forms and derivatives of hexanol (C6H11OH).
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)
Thirteen-carbon butene cyclohexene degradation products formed by the cleavage of CAROTENOIDS. They contribute to the flavor of some FRUIT. Ionone should not be confused with the similarly named ionol.
Glycoprotein moieties on the surfaces of cell membranes that bind concanavalin A selectively; the number and location of the sites depends on the type and condition of the cell.
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.
3-Acetyl-5-sec-butyl-4-hydroxy-3-pyrrolin-2-one. A metabolite found in a strain of the fungus Alternaria tenuis Auct. which functions as an antibiotic with antiviral and antineoplastic properties, and may also act as a mycotoxin.
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.
Established cell cultures that have the potential to propagate indefinitely.
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.
The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.
A 34-amino acid polypeptide antibiotic produced by Streptococcus lactis. It has been used as a food preservative in canned fruits and vegetables, and cheese.
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.
A group of condensed ring hydrocarbons.
A family of enzymes that catalyze the stereoselective, regioselective, or chemoselective syn-dehydrogenation reactions. They function by a mechanism that is linked directly to reduction of molecular OXYGEN.
The rate dynamics in chemical or physical systems.
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.
An autosomal recessive disorder of lipid metabolism. It is caused by mutation of the microsomal triglyceride transfer protein that catalyzes the transport of lipids (TRIGLYCERIDES; CHOLESTEROL ESTERS; PHOSPHOLIPIDS) and is required in the secretion of BETA-LIPOPROTEINS (low density lipoproteins or LDL). Features include defective intestinal lipid absorption, very low serum cholesterol level, and near absent LDL.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.
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)
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.
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.
Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.
The two lipoprotein layers in the MITOCHONDRION. The outer membrane encloses the entire mitochondrion and contains channels with TRANSPORT PROTEINS to move molecules and ions in and out of the organelle. The inner membrane folds into cristae and contains many ENZYMES important to cell METABOLISM and energy production (MITOCHONDRIAL ATP SYNTHASE).
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.
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.
Glycoproteins found on the membrane or surface of cells.
An enzyme that catalyzes the active transport system of sodium and potassium ions across the cell wall. Sodium and potassium ions are closely coupled with membrane ATPase which undergoes phosphorylation and dephosphorylation, thereby providing energy for transport of these ions against concentration gradients.
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.
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.
Cell membranes associated with synapses. Both presynaptic and postsynaptic membranes are included along with their integral or tightly associated specializations for the release or reception of transmitters.
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.
Derivatives of PHOSPHATIDYLCHOLINES obtained by their partial hydrolysis which removes one of the fatty acid moieties.
Cyclic GLUCANS consisting of seven (7) glucopyranose units linked by 1,4-glycosidic bonds.
Synthetic phospholipid used in liposomes and lipid bilayers to study biological membranes. It is also a major constituent of PULMONARY SURFACTANTS.
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.
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.
Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Proteins found in any species of bacterium.
A specific monosialoganglioside that accumulates abnormally within the nervous system due to a deficiency of GM1-b-galactosidase, resulting in GM1 gangliosidosis.
A four carbon linear hydrocarbon that has a hydroxy group at position 1.
Elements of limited time intervals, contributing to particular results or situations.
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
A MANNOSE/GLUCOSE binding lectin isolated from the jack bean (Canavalia ensiformis). It is a potent mitogen used to stimulate cell proliferation in lymphocytes, primarily T-lymphocyte, cultures.
Cholesterol substituted in any position by a keto moiety. The 7-keto isomer inhibits 3-hydroxy-3-methylglutaryl-CoA reductase activity and inhibits cholesterol uptake in the coronary arteries and aorta in vitro.
A synthetic phospholipid used in liposomes and lipid bilayers for the study of biological membranes.
A group of compounds that are derivatives of octadecanoic acid which is one of the most abundant fatty acids found in animal lipids. (Stedman, 25th ed)
A cytotoxic member of the CYTOCHALASINS.
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.
A group of fatty acids that contain 18 carbon atoms and a double bond at the omega 9 carbon.
Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.
The thermodynamic interaction between a substance and WATER.
The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
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)
The process by which semen is kept viable outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).
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.

Stomatocytosis is absent in "stomatin"-deficient murine red blood cells. (1/1645)

To examine the relationship between erythrocyte membrane protein 7. 2b deficiency and the hemolytic anemia of human hereditary stomatocytosis, we created 7.2b knock-out mice by standard gene targeting approaches. Immunoblots showed that homozygous knock-out mice completely lacked erythrocyte protein 7.2b. Despite the absence of protein 7.2b, there was no hemolytic anemia and mouse red blood cells (RBCs) were normal in morphology, cell indices, hydration status, monovalent cation content, and ability to translocate lipids. The absence of the phenotype of hereditary stomatocytosis implies that protein 7.2b deficiency plays no direct role in the etiology of this disorder and casts doubt on the previously proposed role of this protein as a mediator of cation transport in RBC.  (+info)

Vesicle deformation by an axial load: from elongated shapes to tethered vesicles. (2/1645)

A sufficiently large force acting on a single point of the fluid membrane of a flaccid phospholipid vesicle is known to cause the formation of a narrow bilayer tube (tether). We analyze this phenomenon by means of general mathematical methods allowing us to determine the shapes of strongly deformed vesicles including their stability. Starting from a free vesicle with an axisymmetric, prolate equilibrium shape, we consider an axial load that pulls (or pushes) the poles of the vesicle apart. Arranging the resulting shapes of strained vesicles in dependence of the axial deformation and of the area difference of monolayers, phase diagrams of stable shapes are presented comprising prolate shapes with or without equatorial mirror symmetry. For realistic values of membrane parameters, we study the force-extension relation of strained vesicles, and we demonstrate in detail how the initially elongated shape of an axially stretched vesicle transforms into a shape involving a membrane tether. This tethering transition may be continuous or discontinuous. If the free vesicle is mirror symmetric, the mirror symmetry is broken as the tether forms. The stability analysis of tethered shapes reveals that, for the considered vesicles, the stable shape is always asymmetric (polar), i.e., it involves only a single tether on one side of the main vesicle body. Although a bilayer tube formed from a closed vesicle is not an ideal cylinder, we show that, for most practical purposes, it is safe to assume a cylindrical geometry of tethers. This analysis is supplemented by the documentation of a prototype experiment supporting our theoretical predictions. It shows that the currently accepted model for the description of lipid-bilayer elasticity (generalized bilayer couple model) properly accounts for the tethering phenomenon.  (+info)

Monte Carlo simulation of two-component bilayers: DMPC/DSPC mixtures. (3/1645)

In this paper, we describe a relatively simple lattice model of a two-component, two-state phospholipid bilayer. Application of Monte Carlo methods to this model permits simulation of the observed excess heat capacity versus temperature curves of dimyristoylphosphatidylcholine (DMPC)/distearoylphosphatidylcholine (DSPC) mixtures as well as the lateral distributions of the components and properties related to these distributions. The analysis of the bilayer energy distribution functions reveals that the gel-fluid transition is a continuous transition for DMPC, DSPC, and all DMPC/DSPC mixtures. A comparison of the thermodynamic properties of DMPC/DSPC mixtures with the configurational properties shows that the temperatures characteristics of the configurational properties correlate well with the maxima in the excess heat capacity curves rather than with the onset and completion temperatures of the gel-fluid transition. In the gel-fluid coexistence region, we also found excellent agreement between the threshold temperatures at different system compositions detected in fluorescence recovery after photobleaching experiments and the temperatures at which the percolation probability of the gel clusters is 0.36. At every composition, the calculated mole fraction of gel state molecules at the fluorescence recovery after photobleaching threshold is 0.34 and, at the percolation threshold of gel clusters, it is 0.24. The percolation threshold mole fraction of gel or fluid lipid depends on the packing geometry of the molecules and the interchain interactions. However, it is independent of temperature, system composition, and state of the percolating cluster.  (+info)

Cell membrane dynamics and the induction of apoptosis by lipid compounds. (4/1645)

To investigate the induction of apoptosis by some lipid compounds which are a potent inducer of apoptosis, the plasma membrane fluidity of U937 cells was measured using the fluorescent probe, pyrene. The increase of the membrane fluidity was observed immediately after the treatment of cells with lipid inducers. We also found that the trigger of apoptosis was pulled within 30 min after treatment. Data from the dynamic light scattering experiment indicated that lipid inducers were dissolved to form the emulsion. At the very early stage of apoptosis, possibly, the well-controlled transfer of lipid inducers from the emulsion to the lipid layer of cells can bring about the increase of membrane dynamics which might lead to the induction of apoptosis.  (+info)

The interaction of ubiquinone-3 with phospholipid membranes. (5/1645)

The effects of ubiquinone-3 (UQ) on dipalmitoylphosphatidylcholine (DPPC) membrane were studied by surface monolayer, differential scanning calorimetry (DSC) and fluorescence techniques. DPPC and UQ are proved to be freely miscible in the mixed monolayer at an air/water interface, and to be partially miscible in bulk phase, i.e. bilayer and solid phase. There is a condensing interaction between UQ and DPPC in the UQ/DPPC mixed monolayers. The solubility of UQ in the DPPC is about 20 mole% and the solubility of DPPC in UQ is about 10 mole%. The membrane fluidity of DPPC was increased by the addition of UQ and the phase transition temperature was decreased.  (+info)

Interaction of tumor and normal blood cells with ethylene oxide and propylene oxide block copolymers. (6/1645)

Ethylene oxide and propylene oxide block copolymers (pluronics) are widely known as agents that promote drug penetration across biological barriers. We have studied the interaction of normal and malignant blood cells with pluronics L61 and P85 that have different hydrophobicity. SP2/0 myeloma cells accumulated pluronics while normal cells adsorb most of the polymer on the surface. Interaction of pluronics with cells resulted in drastic changes of membrane microviscosity. Tumor cell membrane microviscosity decreased after pluronics adsorption, in contrast to normal cells, whose membrane microviscosity was enhanced. We suppose that sensitivity of tumor cell membrane microviscosity to the pluronics action correlates with its permeability for molecular substances.  (+info)

The yeast multidrug resistance pump, Pdr5p, confers reduced drug resistance in erg mutants of Saccharomyces cerevisiae. (7/1645)

Mutants of Saccharomyces cerevisiae bearing lesions in the ergosterol biosynthetic pathway exhibit a pleiotropic drug-sensitive phenotype. This has been reported to result from an increased permeability of the membranes of the mutant strains to different drugs. As disruption of the yeast multidrug resistance protein, Pdr5p, results in a similar pleiotropic drug-sensitive phenotype, the possibility that Pdr5p may be functioning with a reduced efficiency in these altered sterol backgrounds was examined. To do this, the function of Pdr5p in isogenic strains of S. cerevisiae that have disruptions in the late stages of the ergosterol biosynthesis pathway (ERG6, ERG2, ERG3, ERG4) was studied. A reduced ability of Pdr5p to confer resistance to different drugs in these strains was observed, which did not appear to be dependent solely on the permeability of the membrane towards the drug. A simultaneous examination was made of how the lipid composition might be altering the efficiency of Pdr5p by similar studies in strains lacking phosphatidylserine synthase (encoded by CHO1). The results indicated that the drug sensitivity of the erg strains is, to a significant extent, a result of the reduced efficiency of the Pdr5p efflux pump, and that the membrane environment plays an important role in determining the drug resistance conferred by Pdr5p.  (+info)

Induction of acetylcholinesterase release from erythrocytes in the presence of liposomes. (8/1645)

When human erythrocytes are incubated with liposomes, the release of acetylcholinesterase (AChE) occurs following an induction period [Cook et al. (1980) Biochemistry 19, 4601-4607]. However, the mechanism of the induction has not been elucidated. We examined the relationships among the lipid transfer from liposomes to erythrocytes, the morphological change of erythrocytes, the fluidity of the erythrocyte membrane and the start of AChE release. The AChE release into the liposomes and into shed-vesicle fractions started simultaneously after an induction period. The morphological index (MI) of erythrocytes was approximately 2.8 at the beginning of the release, regardless of the induction period. AChE was not released from the erythrocytes of index 2.8 even in the presence of liposomes if the MI remained at 2.8. Therefore, for the release, erythrocytes needed a further increase of the MI from 2.8. As the rate of lipid transfer increased, the induction period became shorter. No significant lipid release from erythrocytes was detected during the induction period. The initiation of the AChE release was not simply affected by the change in the membrane fluidity of erythrocytes upon interaction with liposomes. These results first demonstrate that AChE release into the shed-vesicle and liposome fractions is triggered by a further increase of the MI from 2.8, which is induced by lipid transfer from liposomes to erythrocytes.  (+info)

Loffhagen, N.; Haertig, C.; Benndorf, D.; Babel, W., 2002: Effects of growth temperature and lipophilic carbon sources on the fatty acid composition and membrane lipid fluidity of Acinetobacter calcoaceticus 69V
Cells maintain membrane fluidity by regulating lipid saturation, but the molecular mechanisms of this homeoviscous adaptation remain poorly understood. We have reconstituted the core machinery for regulating lipid saturation in bakers yeast to study its molecular mechanism. By combining molecular dynamics simulations with experiments, we uncover a remarkable sensitivity of the transcriptional regulator Mga2 to the abundance, position, and configuration of double bonds in lipid acyl chains, and provide insights into the molecular rules of membrane adaptation. Our data challenge the prevailing hypothesis that membrane fluidity serves as the measured variable for regulating lipid saturation. Rather, we show that Mga2 senses the molecular lipid-packing density in a defined region of the membrane. Our findings suggest that membrane property sensors have evolved remarkable sensitivities to highly specific aspects of membrane structure and dynamics, thus paving the way toward the development of genetically
Title:Flow Shear Induced Changes in Membrane Fluidity: Dependence on Cell- Substrate Adhesion Strength. VOLUME: 9 ISSUE: 1. Author(s): Tamal Das, Tapas K. Maiti and Suman Chakraborty. Affiliation:Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur-721302, India.. Keywords:Cell adhesion, Fluidization, Fluorescence recovery after photobleaching, Lipid raft, Membrane fluidity, Traction force microscopy. Abstract:Besides the internal genetic content and the chemical exchanges with external tissue environment, the physical interactions of cancer cells with its microenvironment also provide the guidelines for successful oncogenesis. During its metastatic journey from primary tumor to distant locations of body, a cancer cell is exposed to stresses of diverse origin and kind, of which fluid shear stresses of interstitial and haematogenic nature have been least studied in relation to their impact in cancer progression. Here, we have designed a biomicrofluidic system ...
Increased membrane fluidity, which causes cofactor leakage and loss of membrane potential, has long been documented as a cause for decreased cell growth during exposure to ethanol, butanol, and other alcohols. Reinforcement of the membrane with more complex lipid components is thus thought to be beneficial for the generation of more tolerant organisms. In this study, organisms with more complex membranes, namely, archaea, did not maintain high growth rates upon exposure to alcohols, indicating that more complex lipids do not necessarily fortify the membrane against the fluidizing effects of alcohols. In the presence of alcohols, shifts in lipid composition to more saturated and unbranched lipids were observed in most of the organisms tested, including archaea, yeasts, and bacteria. However, these shifts did not always result in a decrease in membrane fluidity or in greater tolerance of the organism to alcohol exposure. In general, organisms tolerating the highest concentrations of alcohols ...
Purpose: To evaluate the influence of α-crystallin racemization on lens membrane fluidity using the mild heating model based on lens epithelial cells (LECs).. Methods: LECs (SRA01/04) heated at 500C were used as the mild heating model to simulate the ageing process in vitro. After incubation under 500C for 0min, 15min, 30min, 45min and 60min, α-crystallins in LECs were isolated using gel filtration chromatography and processed with acidolysis. The purified samples were treated with o-phtalaldehyde and N-tertbutyloxycarbonyl-L-cysteine for pre-column derivatization before racemization analysis using reversed-phase high performance liquid chromatography (RP-HPLC). To detect the α-crystallin racemization, we calculated the D/L (D/L amino-acid residual) ratio according to the peak area in each chromatogram. Laurdan staining and two-photon confocal microscopy were applied to analyze the lens membrane fluidity of each group with different heating time. Immunofluorescence staining were used to ...
TY - JOUR. T1 - EPITHELIAL-STROMAL INTERACTIONS IN HUMAN BREAST CANCER: IMPLICATIONS FOR CELL ADHESION, MEMBRANE FLUIDITY AND MIGRATION. AU - Angelucci, Cristiana. AU - Maulucci, Giuseppe. AU - Masetti, Riccardo. AU - Lama, Gina. AU - Proietti, Gabriella. AU - Fabbri, Maria Cristina. AU - Sica, Gigliola. PY - 2011. Y1 - 2011. N2 - The migratory/invasive behaviour of breast cancer cells seems to be strongly influenced by their dialogue with neighbouring stromal cells. To verify if this cross-talk may affect some molecular and functional aspects of the cell biology correlated with the metastasizing vocation of tumor cells (i.e. adhesion, membrane fluidity, migration), we co-cultured estrogen receptor (ER)-positive and poorly invasive (MCF-7) or ER-negative and highly invasive (MDA-MB-231) breast cancer cells with normal fibroblasts (NFs) isolated from breast healthy skin or breast tumor stroma (cancer associated fibroblasts, CAFs) in monolayer or in a three-dimensional system (nodules). We ...
The structure and function of the PTEN phosphatase is investigated by studying its membrane affinity and localization on in-plane fluid, thermally disordered synthetic membrane models. The membrane association of the protein depends strongly on membrane composition, where phosphatidylserine (PS) and phosphatidylinositol diphosphate (PI(4,5)P2) act pronouncedly synergistic in pulling the enzyme to the membrane surface. The equilibrium dissociation constants for the binding of wild type (wt) PTEN to PS and PI(4,5)P2 were determined to be Kd∼12 µM and 0.4 µM, respectively, and Kd∼50 nM if both lipids are present. Membrane affinities depend critically on membrane fluidity, which suggests multiple binding sites on the protein for PI(4,5)P2. The PTEN mutations C124S and H93R show binding affinities that deviate strongly from those measured for the wt protein. Both mutants bind PS more strongly than wt PTEN. While C124S PTEN has at least the same affinity to PI(4,5)P2 and an increased apparent affinity
Adult DHA Gummy Fruits were designed for adults who dont like to swallow large fish oil capsules. These gummies contain 225mg of fish oil, 50mg of DHA (docosahexaenoic acid) and 10mg of EPA (eicosapentaenoic acid). These tasty gummies come in orange, lemon and strawberry banana flavors that have no fishy aftertaste. Most of us in the U.S. dont get enough of these essential omega fatty acids because we dont have enough oily fishes in our diets. These essential fatty acids are found in fish such as anchovies, sardines, salmon and mackerel. For those of you who dont like fish, Coromegas DHA Gummy for Adults is the answer for you.. Thousands of clinical and scientific studies have reported that these essential omega fatty acids support heart, brain, eye and joint health. These fatty acids are actually important for every cell in the body. They become integral parts of the plasma membrane and are important for maintaining cell membrane fluidity, ion flows, nutrient uptake, waste removal and cell ...
Lactobacillus acetotolerans is a major microbe contributing to the Chinese liquor fermentation with unknown function. It can be grown well in a high concentration of ethanol. RNA sequencing (RNA-seq) was performed on L. acetotolerans F28 growing in 12% ethanol to determine important genetic mechanisms for both a short and long term adaption to this environment. A genome-wide transcriptional analysis revealed that the most important genetic elements for L. acetotolerans F28 grown in ethanol are related to high levels of stress response and fatty acid biosynthesis, and a reduction of amino acid transport and metabolism after both a short and long time stress. The fatty acid methyl ester analyses showed that most fatty acids were increased in L. acetotolerans F28 after exposure to ethanol while the unsaturated fatty acid octadecenoic acid (C18: 1) was significantly increased. The increasing unsaturated fatty acid biosynthesis in L. acetotolerans F28 might enhance cell membrane fluidity and protect ...
FapR protein from the psychrotrophic species Exiguobacterium antarcticum B7 was expressed and purified, and subsequently evaluated for its capacity to bind to the promoter regions of the fabH1-fabF and fapR-plsX-fabD-fabG operons, using electrophoretic mobility shift assay. The genes that compose these operons encode for enzymes involved in the de novo synthesis of fatty acids molecules. In Bacillus subtilis, FapR regulates the expression of these operons, and consequently has influence in the synthesis of long or short-chain fatty acids. To analyze the bacterial cold adaptation, this is an important metabolic pathway because psychrotrophic microrganisms tend to synthesize short and branched-chain unsaturated fatty acids at cold to maintain cell membrane fluidity. In this work, it was observed that recombinant protein was able to bind to the promoter of the fully amplified fabH1-fabF and fapR-plsX-fabD-fabG operons. However, FapR was unable to bind to the promoter of fapR-plsX-fabD-fabG operon when
Membrane lipid analyses and electron spin resonance (ESR) studies of membrane fluidity were carried out on the red cells of a Japanese patient with hereditary high red cell membrane phosphatidylcholine hemolytic anemia (HPCHA). Increased amounts of phosphatidylcholine (PC) and cholesterol were found in the membrane lipids of the affected patient, despite normal plasma lipids. The order parameter of cholesterol-free pure phospholipid liposomes prepared from this patients red cells was decreased, apparently because of the increased PC. In contrast, the order parameter of the total red cell lipid liposomes (containing free cholesterol) was essentially normal. The overall fluidity of the intact red cells was determined by ESR with a spin probe, 5-SAL. Again, the order parameters were normal in the intact red cells of the patient with HPCHA. This suggests that the concomitant increase of membrane cholesterol and phosphatidylcholine serves to maintain normal membrane fluidity in the HPCHA red cells. ...
If this could seem like a matter of detail, imagine that cognitive functions can be severely influenced by the metabolic process as a whole, due to the disproportionate amount of energy the brain requires just to sustain the survival mechanisms, not to mention its higher functions. Metabolic dysfunctions can thus translate into rational ones. At the micro level, this is a consequence of the problems that neurons have in the distribution of energy, leading to affections in synaptic plasticity, which starts the vicious circle all over again. To relieve the strain, omega-3 acids are a known stimulant of the said plasticity.[4]. Furthermore, numerous patients with mental illnesses (ranging from epilepsy to Alzheimers) exhibit modifications in energy homeostasis, therefore at least a better management of these disorders may become a reality shortly with the aid of correct dietary provisions.. Primarily through the regulation of neurotransmitter pathways and cell membrane fluidity, dietary ...
A common benefit of a successful detox program is weight loss. Our fat cells contain stored toxins, including heavy metals and excess hormones, so it is especially important to encourage functional detox pathways as fat cells are released when losing weight. While undergoing a cleanse, other important physiological considerations include:. *Cell membrane fluidity to allow toxins to exit the cell for removal by the liver, kidneys, and digestive tract ...
Membrane fluidity or membrane viscosity for short range lateral diffusion has best been measured using lipid analog probes that, when interacting, exhibit changes in their spectral…
We report a modular design of vesicular chemosensors by co-embedding a Tb(III) complex and a receptor-sensitizer conjugate in phospholipid vesicles. The binding of phosphate anions to the vesicle surface in aqueous media is detected by a decrease in Tb(III) phosphorescence. The sensory response can be modulated by a variation in the membrane fluidity. ...
Why exactly does the cell membrane become more fluid in higher temperatures than lower? Does it have anything to do with the degree of saturation ...
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TY - JOUR. T1 - Heat stress causes spatially-distinct membrane re-modelling in K562 leukemia cells. AU - Balogh, Gábor. AU - Maulucci, Giuseppe. AU - Gombos, Imre. AU - Horváth, Ibolya. AU - Török, Zsolt. AU - Péter, Mária. AU - Fodor, Elfrieda. AU - Páli, Tibor. AU - Benko, Sándor. AU - Parasassi, Tiziana. AU - de Spirito, Marco. AU - Harwood, John L.. AU - Vígh, László. PY - 2011. Y1 - 2011. N2 - Cellular membranes respond rapidly to various environmental perturbations. Previously we showed that modulations in membrane fluidity achieved by heat stress (HS) resulted in pronounced membrane organization alterations which could be intimately linked to the expression and cellular distribution of heat shock proteins. Here we examine heat-induced membrane changes using several visualisation methods. With Laurdan two-photon microscopy we demonstrate that, in contrast to the enhanced formation of ordered domains in surface membranes, the molecular disorder is significantly elevated within ...
Although cholesterol is essential for membrane fluidity and deformability, the level of its lateral heterogeneity at the plasma membrane of living cells is
The cell danger response (CDR) is the evolutionarily conserved metabolic response that protects cells and hosts from harm. It is triggered by encounters with chemical, physical, or biological threats that exceed the cellular capacity for homeostasis. The resulting metabolic mismatch between available resources and functional capacity produces a cascade of changes in cellular electron flow, oxygen consumption, redox, membrane fluidity, lipid dynamics, bioenergetics, carbon and sulfur resource allocation, protein folding and aggregation, vitamin availability, metal homeostasis, indole, pterin, 1-carbon and polyamine metabolism, and polymer formation. The first wave of danger signals consists of the release of metabolic intermediates like ATP and ADP, Krebs cycle intermediates, oxygen, and reactive oxygen species (ROS), and is sustained by purinergic signaling. After the danger has been eliminated or neutralized, a choreographed sequence of anti-inflammatory and regenerative pathways is activated ...
The cell danger response (CDR) is the evolutionarily conserved metabolic response that protects cells and hosts from harm. It is triggered by encounters with chemical, physical, or biological threats that exceed the cellular capacity for homeostasis. The resulting metabolic mismatch between available resources and functional capacity produces a cascade of changes in cellular electron flow, oxygen consumption, redox, membrane fluidity, lipid dynamics, bioenergetics, carbon and sulfur resource allocation, protein folding and aggregation, vitamin availability, metal homeostasis, indole, pterin, 1-carbon and polyamine metabolism, and polymer formation. The first wave of danger signals consists of the release of metabolic intermediates like ATP and ADP, Krebs cycle intermediates, oxygen, and reactive oxygen species (ROS), and is sustained by purinergic signaling. After the danger has been eliminated or neutralized, a choreographed sequence of anti-inflammatory and regenerative pathways is activated ...
Membranes, Fluidity of - CHEMICAL BIOLOGY - reflects the multidimensional character of chemical biology, focusing in particular on the fundamental science of biological structures and systems, the use of chemical and biological techniques to elucidate
The purpose of this product is to restore membrane fluidity throughout the body and optimize mitochondrial function. It contains a unique mitochondrial fuel
This warped spineknots the ribsto constrict a soundthe voice of painthe body cryingand the echoof a thousandossified cracksgrowing larger. A doctor stridesfrom the hallwayinto the examination rooma hundred research articlesharnessed to moveat the slightest motionof his fingertips. After a skin deep lookhe states I requirebetter colourwith his English accentadding weightto the brush strokethat appliesa primordial…
Background. Karwinskia humboldtiana currently known by the common names buckthorn, wild cherry, tullidora, capulin tullidor, capulincillo, coyotillo, and cacatsin, is a poisonous shrub of the Rhamnaceae family that grows from Southern United States to northern Colombia [1]. Medicinal properties have been attributed to several species of the genus Karwisnkia due to a secondary metabolite with antineo-plastic action on mammalian tumor cells [2].. The ingestion of the green or ripe fruit of Kh causes a flaccid, symmetric, progressive, and ascending palsy of the lower limbs, which, in severe cases may progress to quadriplegia and breathing insufficiency, with victims requiring assisted mechanical ventilation. The neurologic symptoms are similar to those of poliomyelitis, Guillain-Barre syndrome, and other polyradiculoneuritis syndromes, for which it is often mistaken. In Mexico, the accidental ingestion of Kh causes several health problems [3-5], particularly there are numerous reports of poisoning ...
Abstract: Lymphocyte and erythrocyte membrane microviscosites oflipid-protein contact zones and lipid bilayer in blood ofpatients with gastric, urinary bladder and ovary cancers wereinvestigated in comparison with healthy volunteers by means ofcoefficients of eximerization of fluorescent probe pyrene. Thedecrease of membrane fluidity (i.e. the increase ofmicroviscosity) was revealed in blood cell membranes of patientswith diffuse cancers of studied localizations. In the case ofovary cancer membrane fluidity decreased significantly only inpatients with ascite form of the disease. The most pronouncedincrease of microviscosity was observed in lymphocytes andespecially in erythrocytes of practically incurable patients.Interrelationship between microviscosity and other processes thatinfluence on structural properties of membranes under malignancyand their functional role are discussed ...
Detergents and solvents intercalate into a membrane bilayer, alter the membranes stable composition, expand the membrane area and, consequently, decrease membrane tension. A similar approach to expand the membrane area and decrease membrane tension involves the use of fluorescent lipid analogues. Fluorescent lipid analogues can be readily integrated into the outer leaflet of the plasma membrane bilayer of intact cells by spontaneous monomeric lipid transfer. Thus, to further test whether the lamellipodial extension rate is dependent on membrane tension, we have also used fluorescent lipid analogues to expand the membrane area and decrease the membrane tension. When NIH 3T3 fibroblasts are incubated with 5 mM of a Bodipy-labeled sphingomyelin analogue, C5-DMB-SM, and washed, a continuous plasma membrane fluorescence was observed (Fig. 4 a). A similar plasma membrane staining pattern was observed after cells were incubated with an FITC-phosphatidylethanolamine analogue, FITC-PL (Fig. 4 b), or a ...
CLX (celecoxib), a selective COX-2 (cyclo-oxygenase-2) inhibitor, has numerous pleiotropic effects on the body that may be independent of its COX-2 inhibitory activity. The cancer chemopreventive ability of CLX, particularly in CRC (colorectal cancer), has been shown in epidemiological studies. Here we have, for the first time, examined the biophysical effects of CLX on the cellular membranes of COX-2 expressing (HT29) and COX-2 non-expressing (SW620) cell lines using ATR-FTIR (attenuated total reflectance-Fourier transform IR) spectroscopy and SL-ESR (spin label-ESR) spectroscopy. Our results show that CLX treatment decreased lipid fluidity in the cancer cell lines irrespective of COX-2 expression status. As metastatic cells have higher membrane fluidity, we examined the effect of CLX on the metastatic potential of these cells. The CLX treatment efficiently decreased the proliferation, anchorage-independent growth, ability to close a scratch wound and migration and invasion of the CRC cell ...
TY - JOUR. T1 - Physicochemical perturbation of α-linolenic acid related to cell proliferation. AU - Fukui, H.. AU - Sato, Toshinori. AU - Sunamoto, J.. PY - 1994. Y1 - 1994. N2 - The influence of fatty acids, α-linolenic acid (ALA), and linoleic acid (LA), on lipid membrane dynamics and cell proliferation was investigated. Electron-spin resonance measurements with 2-hexyl-2-(10-methoxycarbonyldecyl)-4,4-dimethyl-3-oxazolidinyloxyl revealed that the penetration of ALA or LA into the liposomal membrane causes an increase in the membrane fluidity and a decrease in the phase-transition temperature of the lipid membrane. When human colon cancer cells (RPMI4788 and BM314) and normal mouse fibroblast (L-cell) were incubated with ALA, the membrane fluidity of the cancer cells significantly increased over that of normal cells. ALA made the cancer cell membrane more fluid than did LA. When ALA was administered at a concentration of 40 μg ml-1, it showed a strong cytotoxicity against the cancer cells, ...
This chapter focuses on the various mechanisms by which membrane fluidity is modulated in bacteria vis-à-vis its importance in cold adaptation. A detailed update on the perception and transduction of low-temperature signals in bacteria is also included. Subsequently, it was found that trans-monounsaturated are predominant in gram-negative bacteria and are synthesized by direct isomerization of cis-unsaturated fatty acids to trans-unsaturated fatty acids without shifting of a double bond. One of the predominant signal transduction mechanisms employed by bacteria is the phosphotransfer pathway commonly referred to as the two-component signal transduction system, which consists of a sensor kinase (histidine kinase) and a response regulator, found in bacteria, Archaea, and Eukarya. The first direct evidence for the two-component signal transduction mechanism involved in sensing cold has come from studies on Bacillus subtilis. Modulation in membrane fluidity appears to be crucial for low-temperature sensing
Organelle remodeling processes are evolutionarily conserved and involved in cell functions during development, aging, and cell death. Some endogenous and exogenous molecules can modulate these processes. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid, has mainly been considered as a modulator of plasma membrane fluidity in brain development and aging, while DHAs role in organelle remodeling in specific neural cell types at the ultrastructural level remains largely unexplored. DHA is notably incorporated into dynamic organelles named lipid bodies (LBs). We hypothesized that DHA could attenuate the inflammatory response in lipopolysaccharide (LPS)-activated microglia by remodeling LBs and altering their functional interplay with mitochondria and other associated organelles. We used electron microscopy to analyze at high spatial resolution organelle changes in N9 microglial cells exposed to the proinflammogen LPS, with or without DHA supplementation. Our results revealed that DHA
Source: https://www.genome.gov/genetics-glossary/Plasma-Membrane Campbell Biology Variations in the cell membrane lipid compositions of many species appear to be evolutionary adaptations that maintain the appropriate membrane fluidity under specific environmental conditions. For instance, fishes that live in extreme cold have membranes with a high proportion of unsaturated hydrocarbon tails, enabling their membranes to remain fluid. At the…
Fluidity Extract Liquidizer turns thick extracts into flowing oil. Its odorless, flavorless, and made from natural ingredients. It does not contain PG, PEG, or VG. It combines smoothly with all types of extracts and will stay blended without additional additives. Does not contain THC, CBD, or vitamin E. Fluidity is designed for harder-to-liquidize concentrates. For concentrates that already flow well, check out #710 Pure Liquidizer.. ...
Lecturer: Timothy J. Healey. Title: Global symmetry-breaking bifurcation in a model for 2-phase lipid-bilayer vesicles - analysis and computation. Abstract: We study a model for lipid-bilayer membrane vesicles exhibiting phase separation, incorporating a phase field together with membrane fluidity and bending elasticity. We prove the existence of a plethora of equilibria in the large, corresponding to symmetry-breaking solutions of the Euler-Lagrange equations. We also numerically compute a special class of such solutions, namely those possessing icosahedral symmetry. We overcome several difficulties along the way. Due to inherent surface fluidity combined with finite curvature elasticity, neither the Eulerian (spatial) nor the Lagrangian (material) description of the model lends itself well to analysis. This is resolved via a singularity-free radial-map description, which effectively eliminates the grossly under-determined mid-plane deformation. We then use well known group-theoretic selection ...
Membrane lipids play an important role in the control of cellular functions. Emerging evidence from our laboratory and other groups suggest that autism spectrum disorders (ASD) are connected with abnormalities in lipid metabolism and oxidative stress. We have reported previously altered levels of amino-glycerophospholipids (AGP) in the membrane and plasma in autism. Membrane fluidity, a marker of unsaturated fatty acids, was decreased in the erythrocyte membranes of children with autism as compared to typically developing siblings. Our results suggest increased peroxidation of lipids in the plasma, cerebellum and temporal cortex of autistic subjects as compared to control subjects. Decreased serum levels of ceruloplasmin (copper transporting protein) and transferrin (iron-transporting protein), major antioxidant proteins, were observed in autism that correlated with loss of previously acquired language skills in these subjects. Copper could selectively affect the levels of AGP in the membrane of ...
Introduction to the Biology. Cell theory: cell and organisms. Structure and function of the proteins: primary, secondary, tertiary and quaternary structure. The enzymes. Structural and functional organization of eukaryotic and prokaryotic cells. Organelles: structure, function and evolution. Smooth and Rough reticulum, the Golgi apparatus, the lysosomes and peroxisomes.Viruses. The Metabolism and the energetic bases of the vital phenomena: the functions performed by ATP. Cell membranes: structure and function. The Endocytosis and Exocytosis. Membrane Fluidity. Role of membrane phospholipids and cholesterol. Intrinsic and Extrinsic protein. Glycoproteins and Glycolipids. The mechanisms of transport across the membrane: simple and facilitated diffusion. The active transport. Signal Transduction. The Hormones.The G-coupled receptors. Role of AMPc . Mechanisms of interaction between cells: CAM (Cadherins and Integrins). The genetic information : The nuclear genome: structure and function.The DNA ...
Phosphatidylserine USAGE: Take 1 - 3 capsules daily with food, or as directed by your qualified health consultant. Best kept refrigerated. Phosphatidylserine (PS) is a natural phospholipid that is an essential component of cell membranes. Cogni-PS promotes brain function by increasing neuronal membrane fluidity (cell-to-cell communication), resulting in improved cognition. Also, Cogni-PS protects against stress by mitigating the actions of cortisol (catabolic stress hormone.) Cogni-PS is a concentrated form of phosphatidylserine derived from an enzymatic process of soy phospholipids. Keep out of the reach of children. SUPPLEMENT FACTS Serving Size 1 Capsule Amount % DV -------------------------------------------------------------------------------- Phosphatidylserine (PS) 100 mg * -------------------------------------------------------------------------------- Phosphatidylcholine (PC) 12 mg * -------------------------------------------------------------------------------- Gamma
PhosphatidylserineUSAGE: Take 1 - 3 capsules daily with food, or as directed by your qualified health consultant. Best kept refrigerated. Phosphatidylserine (PS) is a natural phospholipid that is an essential component of cell membranes. Cogni-PS™ promotes brain function by increasing neuronal membrane fluidity (cell-to-cell communication), resulting in improved cognition. Also, Cogni-PS™ protects against stress by mitigating the actions of cortisol (catabolic stress hormone.)Cogni-PS™ is a concentrated form of phosphatidylserine derived from an enzymatic process of soy phospholipids.Keep out of the reach of children.SUPPLEMENT FACTSServing Size 1 CapsuleAmount % DV--------------------------------------------------------------------------------Phosphatidylserine (PS) 100 mg *--------------------------------------------------------------------------------Phosphatidylcholine (PC) 12 mg *--------------------------------------------------------------------------------Gamma tocopherol 3 mg *----------
Learmonth, Robert P. and Gratton, Enrico (2002) Assessment of membrane fluidity in individual yeast cells by Laurdan generalised polarisation and multi-photon scanning fluorescence microscopy. In: Fluorescence spectroscopy, imaging and probes: new tools in chemical, physical and life sciences. Fluorescence: Methods and Applications (2). Springer-Verlag, Heidelberg, Germany, pp. 241-252. ISBN 3-540-42768-6 ...
Researchers from Skoltech and the Mental Health Research Center have found 22 lipids in the blood plasma of people with schizophrenia that were associated with lower symptom improvement over time during treatment. These can help track resistance to medication that affects over a third of patients. The paper was published in the journal Biomolecules. Studies suggest that up to 34% of people living with schizophrenia can be resistant to two or more antipsychotic medications used to treat the disorder. Individual responses vary greatly, and there are no satisfactory biomarkers of treatment response yet, which can often turn finding the right medication into a painful and protracted guessing game. Recently researchers have turned to studying lipids and the important function they are now known to play in both the properties and functionality of the brain, such as membrane fluidity and permeability, retrograde signaling, neural plasticity, and neurotransmitter release modulation. Lipidomics is a ...
if you compare plant at ambiant temperature to plant at 10 degrees, plant at 10 degrees are going to be smaller because of stress caused by cold whitch involve regulation of growing, regulation of genetic program to be able to survive to cold temperature. exemples of this regulation are to permit synthesis of proteins and sugar who are cryoprotectant (chaperonin, ....), to change the membrane fluidity ...
Steroids a biologically active compound where the structure is four rings arranged in specific molecular arrangement. It is found naturally in plants and animals and the core structure is comprised of seventeen carbon atoms. It alters membrane fluidity and functions as signaling molecules. It can produced synthetically which resembles
TY - CHAP. T1 - Chapter 10 M-T7. Measuring Chemokine-Modulating Activity. AU - Bartee, Mee Y.. AU - Dai, Erbin. AU - Liu, Liying. AU - Munuswamy-Ramanujam, Ganesh. AU - Macaulay, Colin. AU - McIvor, Dana. AU - McFadden, Grant. AU - Lucas, Alexandra R.. PY - 2009/5/14. Y1 - 2009/5/14. N2 - Chemokines are important for activation of a host of cellular immune and inflammatory responses including cell signaling, activation, and communication. M-T7, a myxoma virus protein, inhibits the activity of chemokines by direct binding to chemokines and/or with glycosaminoglycans (GAGs). To study the effects of this chemokine-modulating protein (CMP), we use a variety of in vitro and in vivo techniques to evaluate M-T7 inhibition of inflammatory cells. To quickly analyze the effects of M-T7, changes in cell adhesion and membrane fluidity are measured as well as cell migration in mouse ascites. For more physiological analyses, an aortic transplant model in rodents is used to assess change in inflammatory cell ...
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As best as I could do, this list represents my favorite dramatic scenes of the last decade. Some of the scenes are insightful, others moving, suspenseful or educational, but all of them are true drama. As always, although they are ordered, there is a lot of fluidity on this list. Feel free to comment on any of them, or suggest ones that I may have missed. ...
ADVANCED CONTROL OF AN INDUSTRIAL CIRCULATING FLUIDIZED BED BOILER USING FUZZY LOGICERK K I KA RP PANE N Department of Process Engineering ...
International Thermodynamic Tables of the Fluid State, Argon, The last part of the book illustrates different tables that are closely associated with the constituent and IUPAC tables. The text caters to people who are interested in studying this field of chemistry, including undergraduates and postgraduates. Chapter 2 highlights.
2 Refreshing Fluidity Humans are mostly water, reflecting our oceanic heritage. How do we cultivate responsiveness and resonance, rather than rigidity?. Lying comfortably on the floor, eyes closed:. -Engage the theatre of your imagination. Visualize your body as a giant water balloon.. -Begin rolling the balloon by pouring its fluid contents. Dissolve your boney joints and tight places. Sometimes it helps to move slowly, feeling the continuity of all the tissues.. -Now imagine being moved by a fluid context, an ocean wave or river current moving the volume of your body from outside-propelling, rolling your skin through space.. -Now move from the skin itself-the mutable membrane. Shape-shift your body through the container of the skin. -Explore the fluid body on your own: skin to depth inside, skin to depth outside. What does your body dream up next?. -Pause, noticing all the fluidity that is happening in what we call stillness.. Rolling the three body weights. -Starting with your head, begin ...
The technical field to which the invention relates.. This invention relates to fluid discrete environments and compositions containing such discrete medium, and to methods of making and using such discrete environments and products.. The level of technology. Fluidity is a desirable characteristic for most products, because it provides the ability distribution, which may allow accurate controlled dosing. Solid products do not provide a uniform rate of pouring or removal of the product in a narrow volumetric fluid flow, particularly when the width of the stream is narrow compared with the particle size of the product. When solid foods do not provide the desired degree of fluidity, products, typically made in the form of a fluid, in particular liquids. Unfortunately, these fluids require complex dosing equipment, or they get dirty, because they can drip after dispensing and thereby contaminate surfaces such as holes containers or associated metering device. Further, contamination may hinder the ...
Once upon a time, there was a certain clarity in the world of sexuality. Regardless of whether one believed a homosexual orientation was innate or a matter of choice, the sexual orientations were easily and clearly defined
Once upon a time, there was a certain clarity in the world of sexuality. Regardless of whether one believed a homosexual orientation was innate or a matter of choice, the sexual orientations were easily and clearly defined
It is said the living organisms are influenced by active oxygen, which increases the amount of the cell membrane of the lipid peroxide and decreases the fluidity of the cell membrane with age, causing the organisms to lose flexibility in the cell membrane as they grow old ...
It suddenly occurred to me that if I turned some of these into a bracelet then they would be there to see and touch whenever I was wearing it...almost like worry beads I guess. I pulled out half a dozen of the blue cream beads because they pair well with my daily uniform of jeans and would therefore get lots of wear. Its a fairly simple design with the beads wire wrapped and linked to each other and Ive interspersed them with labradorite dangles to give some fluidity and movement to the piece ...
These dreams pourIn to me with fluidity,Like milk from a jug,Like clotted cream, fromA place in time bothNew and old to certainDegrees, where I am notAs one would be, whenAwake in passive dailyRoutines. This drinkPlays tricks on me,A mind as arid asDeserts devoid of oasesAnd mysteries sealed inCamel humps and dunesThat burn beneath my feet.Too…
► Everything about fluidity.nonstop Meat processing, e.g. process description with flowsheets and equipment choice with links to suppliers.
All of these effects bet on membrane fluidity. It's thought that agaric acid activates the opening of membrane pores due to the ... Its dependence on membrane fluidity". Mitochondrion. 5 (4): 272-81. doi:10.1016/j.mito.2005.05.002. PMID 16050990. García, ... It facilitates the efflux of accumulated Ca2+, disrupts the potential of the membrane and causes mitochondrial lumps. ...
Membrane fluidity. *Monitoring electropermeabilization of cells. *Nuclear antigens. *Oxidative burst. *pH, intracellular ... Apoptosis (quantification, measurement of DNA degradation, mitochondrial membrane potential, permeability changes, caspase ... they may also be attached to a chemical entity with affinity for the cell membrane or another cellular structure. Each ... This patented technology allows a highly accurate cell analysis and provides additional information like membrane capacitance ...
... s have two principal biological functions: as important components of cell membranes which alter membrane fluidity; and ... the latter is a structural component of cell membranes which helps determine the fluidity of cell membranes and is a principal ... and steroids and phospholipids are components of cell membranes. Steroids such as cholesterol decrease membrane fluidity. ... Ergosterol is analogous to the cholesterol found in the cellular membranes of animals (including humans), or the phytosterols ...
Eventually, membrane fluidity and activity of membrane bound enzymes become depleted. It has also been shown to inhibit ... This structure provides the membrane with fluidity. This occurs by transforming lanosterol into 4,4'-dimethyl cholesta-8,14,24- ... Lanosterol is found within the yeast plasma membrane. It is a class of methylsterol. Within a normal yeast cell, lanosterol is ... This process creates zymosterol: a major constituent in the ergosterol biosynthesis pathway for the creation of cell membrane ...
The way most cells react to the cold is by changing the fluidity of the cellular membrane, but this particular bacterium has ... This is due to various complications of freeze-drying, including the formation of ice crystals, loss of membrane fluidity, and ... "Subcellular membrane fluidity of Lactobacillus delbrueckii subsp. bulgaricus under cold and osmotic stress". Applied ...
Carlini E, Palmerini CA, Cosmi EV, Arienti G (July 1997). "Fusion of sperm with prostasomes: effects on membrane fluidity". ... They possess an unusual lipid composition and a tight and highly ordered structure of their lipid bilayer membrane, resembling ... Minelli A, Moroni M, Martínez E, Mezzasoma I, Ronquist G (November 1998). "Occurrence of prostasome-like membrane vesicles in ... Ronquist G (June 1987). "Effect of modulators on prostasome membrane-bound ATPase in human seminal plasma". European Journal of ...
Cooper RA, Durocher JR, Leslie MH (July 1977). "Decreased fluidity of red cell membrane lipids in abetalipoproteinemia". The ...
"Decreased fluidity of red cell membrane lipids in abetalipoproteinemia". J. Clin. Invest. 60 (1): 115-21. doi:10.1172/JCI108747 ... Alterations in membrane lipids are seen in abetalipoproteinemia and liver dysfunction. Alteration in membrane structural ... This causes abnormalities of membrane of RBC causing remodeling in spleen and formation of acanthocytes. In ... Acanthocytes arise from either alterations in membrane lipids or structural proteins. ...
The lipid bilayer gives fluidity and elasticity to the membrane. Small amounts of carbohydrates are also found in the cell ... The membrane bilayer is not always flat. Local curvature of the membrane can be caused by the asymmetry and non-bilayer ... Cell membrane proteins and glycoproteins do not exist as single elements of the lipid membrane, as first proposed by Singer and ... Another way to define membrane domains is the association of the lipid membrane with the cytoskeleton filaments and the ...
These alterations result in changes in membrane fluidity and permeability. These processes along with the accumulation of lipid ... Their amphipathic nature drives the formation of the lipid bilayer structure of membranes. The cell membrane seen under the ... In the cell membrane, the two layers of phospholipids are arranged as follows: the hydrophobic tails point to each other and ... Thus, neural membrane phospholipids are a reservoir for second messengers. They are also involved in apoptosis, modulation of ...
It activates calcium ATPase by increasing membrane fluidity[citation needed] . It binds to the D subunit of ATP synthase and ...
doi:10.1016/0300-9629(78)90273-6. Clarke JR (1977). "Fluidity-induced changes in diffusion through membranes: a predictive ...
Expression of heat shock proteins and regulation of membrane fluidity are just two of many biochemical methods organisms use to ... Los D.A., Murata N. (2004). "Membrane fluidity and its roles in the perception of environmental signals". Biochimica et ... In response to changes in temperature, organisms can change the biochemistry of cell membranes making them more fluid in cold ... temperatures and less fluid in warm temperatures by increasing the number of membrane proteins. Organisms may also express ...
The main function of cholesterol is controlling the cell membrane fluidity. Steroid - see also steroidogenesis: Steroids are ... Membrane lipid biosynthesis occurs in the endoplasmic reticulum membrane. The phosphatidic acid is also a precursor for ... There are two major classes of membrane lipids: glycerophospholipids and sphingolipids. Although many different membrane lipids ... Other types of lipids found in the body are fatty acids and membrane lipids. Lipid metabolism is often considered as the ...
For example, it was used to help establish the existence of a "fluidity gradient" across the membrane bilayer of some tumor ... Schroeder F (November 1978). "Differences in fluidity between bilayer halves of tumour cell plasma membranes". Nature. 276 ( ... with minimal effects on the biophysical properties of the membrane. Molecular interactions with neighboring membrane lipids ... α-Parinaric acid is also used as a chromophore to study interactions between membrane proteins and lipids. Because of the ...
... results in the reduced fluidity of their membranes because molecules are squeezed together. Fluidity in cell membranes ... In high pressure environments, bilayer cellular membranes experience a loss of fluidity. Deep-sea cellular membranes favor ... have adapted to this circumstance by increasing the proportion of unsaturated fatty acids in the lipids of the cell membranes. ... phospholipid bilayers with a higher proportion of unsaturated fatty acids, which induce a higher fluidity than their sea-level ...
Lee, R. E.; Damodaran, K.; Yi, S. X.; Lorigan, G. A. (2006). "Rapid Cold-Hardening Increases Membrane Fluidity and Cold ... When temperature drops, the membrane fluidity, RNA and DNA stability, and enzyme activity change. These, in turn, affect ... Cold increases cell membrane permeability and makes the cell shrink, as water is drawn out when ice is formed in the ... To retain the surface area of the cell membrane so it will be able to regain its former volume when temperature rises again, ...
Tang C, Castoldi AF, Costa LG (April 1993). "Effects of the muscarinic agonist oxotremorine on membrane fluidity in rat ...
Also, the cortical NMDA receptor influences membrane fluidity, and is altered in Alzheimer's disease. When the cell is infected ... Each cell membrane can have several kinds of membrane receptors, with varying surface distributions. A single receptor may also ... Cell surface receptors (membrane receptors, transmembrane receptors) are receptors that are embedded in the plasma membrane of ... "Cortical NMDA Receptor Properties and Membrane Fluidity Are Altered in Alzheimer's Disease". Dementia. 7 (4): 210-214. doi: ...
Among other things, arachidonic acid helps to maintain hippocampal cell membrane fluidity. It also helps protect the brain from ... of membranes of the body's cells, and is abundant in the brain, muscles, and liver. Skeletal muscle is an especially active ...
... s influence membrane fluidity and membrane protein trafficking, thereby regulating neurotransmission and receptor ... In 1974, the effects of temperature on membrane behavior had led to the proposal of "clusters of lipids" in membranes and by ... Currently synthetic membranes are studied; however, there are many drawbacks to using these membranes. First, synthetic ... This allows information of the diffusivity of particles in the membrane to be extracted as well as revealing membrane corrals, ...
Majority of the membrane is composed of phospholipids, which exhibit fluidity like oil. The phospholids are not just stationary ... "Is a fluid-mosaic model of biological membranes fully relevant? Studies on lipid organization in model and biological membranes ... They made a seminal model for the structure of cell membranes, which they named the Fluid Mosaic Model, and published in a 12- ... With S.J. Singer, Nicolson published a paper titled "The fluid mosaic model of the structure of cell membranes" in 1972, which ...
Unsaturated fatty acids increase the fluidity of the membrane and stabilize it under lower temperatures. DesK is the sensor ... DesK is a membrane-associated kinase and DesR is a transcriptional regulator of the des gene. The regulation responds to ... In bacteria with membranes composed mainly of omega-alicyclic fatty acids, the supply of cyclic carboxylic acid-CoA esters is ... Phospholipids form the bulk of the lipid bilayers that make up cell membranes and surround the organelles within the cells (e.g ...
... which increases the fluidity of the membranes. In addition, carotenoids are present in the membrane, which help modulate the ... Compared to longer saturated fatty acids, incorporating this type of fatty acid allows for the lipid cell membrane to have a ... They must also overcome the stiffening of their lipid cell membrane, as this is important for the survival and functionality of ... To accomplish this, psychrophiles adapt lipid membrane structures that have a high content of short, unsaturated fatty acids. ...
"Salt-induced changes in lipid composition and membrane fluidity of halophilic yeast-like melanized fungi". Extremophiles. 8 (1 ... Adaptation to high concentrations of salt are also accompanied by changes in membrane lipid composition, mainly by increasing ...
Increased PUFA concentrations decrease the membrane fluidity and help the bacterium thrive in the cold temperatures. The exact ... "Eicosapentaenoic acid plays a beneficial role in membrane organization and cell division of a cold-adapted bacterium, ... reduction outer membrane proteins involved in respiration. A pressure related operon is believed to play an integral role in ... These categories were created from an evaluation of the 16s rRNA sequences as well as a comparison of membrane lipid ...
Cis unsaturated fatty acids, however, increase cellular membrane fluidity, whereas trans unsaturated fatty acids do not. trans ... Studies on the cell membranes of mammals and reptiles discovered that mammalian cell membranes are composed of a higher ... to maintain greater membrane fluidity (and functionality) at the lower temperatures. The following table gives the fatty acid, ... This fatty acid composition results in a more fluid cell membrane but also one that is permeable to various ions (H+ & Na+ ), ...
... is the adaptation of the cell membrane lipid composition to keep the adequate membrane fluidity. The ... and proper separation of membranes during cell division. A fundamental biophysical determinant of membrane fluidity is the ... Regulating membrane fluidity is especially important in poikilothermic organisms such as bacteria, fungi, protists, plants, ... maintenance of proper cell membrane fluidity is of critical importance for the function and integrity of the cell, essential ...
... likely serves as a fluidity-buffering component of biological membranes, similar to sterols and hopanols. The ... From molecular fossils to procaryotic membranes. Trends Biochem Sci 7, 236-239.. ...
Cholesterol is required to build and maintain cell membranes; it regulates membrane fluidity over a wide range of temperatures ... assisting in the formation of lipid rafts in the plasma membrane. It also reduces the permeability of the plasma membrane to ... The hydroxyl group on cholesterol interacts with the polar head groups of the membrane phospholipids and sphingolipids, while ... It plays a central role in many biochemical processes, such as the building of cell membranes and the synthesis of steroid ...
... essential for maintaining both membrane structural integrity and fluidity.. chromosome. A threadlike strand of DNA in the cell ... membrane potential. When a nerve or muscle cell is at "rest", its membrane potential is called the resting membrane potential. ... cell membrane. The semipermeable membrane surrounding the cytoplasm of a cell.. cell nucleus. The "control room" for the cell. ... mucous membrane. A membrane that lines various cavities in the body and covers the surface of internal organs.. multicellular. ...
1987). "13C NMR studies of lipid fatty acyl chains of chloroplast membranes". Indian Journal of Biochemistry and Biophysics 24 ... fluidity) இதன் காரணமாகவே கொண்டுள்ளது.[9] மேலும், பசுங்கணிகங்களின் உயர் பிரிகை 13-C NMR நிறமாலையில் லினோலெனிக அமிலத்திற்கு ... Biochemistry of Lipids, Lipoproteins and Membranes. Amsterdam: Elsevier. 2002. பன்னாட்டுத் தரப்புத்தக எண்:978-0-444-51139-3. ... "Phospholipid/cholesterol model membranes: formation of cholesterol crystallites". Biochimica et Biophysica Acta 1610 (2): 187- ...
The lipid composition is important as it defines many physical properties such as membrane permeability and fluidity. ... Membrane lipids. The most common red blood cell membrane lipids, schematically disposed as they are distributed on the bilayer ... Their membrane plays many roles in this. These functions are highly dependent on the membrane composition. The red blood cell ... likely enabling the red cell to maintain its favorable membrane surface area by preventing the membrane from collapsing ( ...
... modify plasma membrane properties, like fluidity and formation of liquid ordered domains, influencing membrane ... a hopanoid compound found in some bacterial cell membranes, and cholesterol, a sterol compound found in eukaryotic membranes.[5 ... where they are thought to minimise water loss across the membrane to the air.[6] In the actinomycete Frankia, the hopanoids in ... In many bacteria hopanoids may play roles in the adjustment of cell membrane permeability in adaptation to extreme ...
Arachidonic acid preserves hippocampal neuron membrane fluidity in senescent rats»։ Neurobiology of Aging 28 (8): 1179-1186։ ... Darios F, Davletov B (2006)։ «Omega-3 and omega-6 fatty acids stimulate cell membrane expansion by acting on syntaxin 3»։ ...
Cholesterol, a major component of animal plasma membranes, regulates the fluidity of the overall membrane, meaning that ... plasmatic membrane (Pfeffer, 1900),[13] plasma membrane, cytoplasmic membrane, cell envelope and cell membrane.[14][15] Some ... The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the ... Intracellular membranes. The content of the cell, inside the cell membrane, is composed of numerous membrane-bound organelles, ...
It is hypothesized that increasing cell membrane fluidity by increasing PUFA concentration might result in an enhanced number ... Diet also has the potential to change the ratio of polyunsaturated to saturated phospholipids in cell membranes. The percentage ... "Dietary intervention increases n-3 long-chain polyunsaturated fatty acids in skeletal muscle membrane phospholipids of obese ...
This surface is coated with a rough plastic membrane or a screen, which allows naturally occurring algal spores to settle and ... Polyunsaturated fats are known for their ability to retain fluidity at lower temperatures. While this may seem like an ...
Unsaturated chains have a lower melting point, hence these molecules increase the fluidity of cell membranes. ... Membrane composition as a metabolic pacemakerEdit. Studies on the cell membranes of mammals and reptiles discovered that ... to maintain greater membrane fluidity (and functionality) at the lower temperatures.[21][22] ... Hulbert AJ (July 2003). "Life, death and membrane bilayers". The Journal of Experimental Biology. 206 (Pt 14): 2303-11. doi: ...
Thus membranes are fluidized only by large quantities of anaesthetics, but there are no changes in membrane fluidity when ... However, changes in membrane density and fluidity in the presence of clinical concentrations of general anaesthetics are so ... A small increase in body temperature affects membrane density and fluidity as much as general anaesthetics, yet it does not ... Each bilayer membrane has a distinct profile of how lateral pressures are distributed within it. Most membrane proteins ( ...
... where they play an important structural role in the regulation of membrane fluidity and permeability and also influence the ... Abe F, Usui K, Hiraki T (September 2009). "Fluconazole modulates membrane rigidity, heterogeneity, and water penetration into ... and overexpression of membrane efflux transporters can all lead to resistance to these antifungals.[17][18][19][20] ... where it plays an essential role in mediating membrane permeability.[3] In fungi, CYP51 catalyzes the demethylation of ...
For all cells, membrane fluidity is important for many reasons. It enables membrane proteins to diffuse rapidly in the plane of ... This article is about various membranes in living things. For the membranes surrounding cells, see cell membrane. ... In animal cells, membrane fluidity is modulated by the inclusion of the sterol cholesterol. This molecule is present in ... Proteins are adapted to high membrane fluidity environment of lipid bilayer with the presence of an annular lipid shell, ...
Because of the size exclusion, the colloidal particles are unable to pass through the pores of an ultrafiltration membrane with ... In many interesting cases optical fluidity is used to control colloid suspensions.[25][26] ... The smaller the size of the pore of the ultrafiltration membrane, the lower the concentration of the dispersed colloidal ... because of the process of ultrafiltration occurring in dense clay membrane.[35] The question is less clear for small organic ...
The surface of a liquid behaves like an elastic membrane in which surface tension appears, allowing the formation of drops and ... The liquid then becomes a viscoelastic medium that shows both the elasticity of a solid and the fluidity of a liquid, depending ...
"Arachidonic acid preserves hippocampal neuron membrane fluidity in senescent rats". 《Neurobiology of Aging》 28 (8): 1179-1186. ... Darios, F; Davletov, B (2006). "Omega-3 and omega-6 fatty acids stimulate cell membrane expansion by acting on syntaxin 3". 《 ...
1987). "13C NMR studies of lipid fatty acyl chains of chloroplast membranes". Indian Journal of Biochemistry and Biophysics 24 ... fluidity) இதன் காரணமாகவே கொண்டுள்ளது. [9] மேலும், பசுங்கணிகங்களின் உயர் பிரிகை 13-C NMR நிறமாலையில் லினோலெனிக அமிலத்திற்கு ... "Phospholipid/cholesterol model membranes: formation of cholesterol crystallites". Biochimica et Biophysica Acta 1610 (2): 187- ... "Biochemistry of Lipids, Lipoproteins and Membranes (4th ). Amsterdam: Elsevier. 2002. பக். 373-407. ISBN 978-0-444-51138-6. ...
Membrane biology. *Membrane channel. *Membrane contact site. *Membrane curvature. *Membrane fluidity. *Membrane lipids ...
Lipids forming the thylakoid membranes, richest in high-fluidity linolenic acid[7] are synthesized in a complex pathway ... and properly target proteins to the correct membrane system. The outer membrane, plasma membrane, and thylakoid membranes each ... Integral membrane proteinsEdit. Thylakoid membranes contain integral membrane proteins which play an important role in light ... 2.3 Inner membrane. 3 Thylakoid ◄ You are here. 3.1 Thylakoid space (lumen). 3.2 Thylakoid membrane. 4 Stromal thylakoid. 5 ...
... correspondingly changing cell membrane fluidity; full impact of such changes is not fully understood, but it is known that the ... It is hypothesized that increasing cell membrane fluidity by increasing PUFA concentration might result in an enhanced number ... In the long term, diet has the potential to change the ratio of polyunsaturated to saturated phospholipids in cell membranes, ... on the membrane of the cell decreases somewhat.[63] In the presence of a higher than usual level of insulin (generally caused ...
Cholesterol, a major component of animal plasma membranes, regulates the fluidity of the overall membrane, meaning that ... The membrane also contains membrane proteins, including integral proteins that go across the membrane serving as membrane ... plasmatic membrane (Pfeffer, 1900),[15] plasma membrane, cytoplasmic membrane, cell envelope and cell membrane.[16][17] Some ... The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the ...
... is regulated by membrane fluidity in model lipid bilayers". European Journal of Biochemistry. 269 (18): 4656-65. doi:10.1046/j. ...
In particular, biological membranes and cell membranes are a form of liquid crystal. Their constituent molecules (e.g. ... Nematics have fluidity similar to that of ordinary (isotropic) liquids but they can be easily aligned by an external magnetic ... phospholipids) are perpendicular to the membrane surface, yet the membrane is flexible. These lipids vary in shape (see page on ... Lipid molecules can flip from one side of the membrane to the other, this process being catalyzed by flippases and floppases ( ...
... this is crucial because oxidative stress affects sperm function by altering membrane fluidity, permeability and impairing sperm ... Levels of malondialdehyde can be also considered (as a marker of lipid peroxidation) to assess the membrane damage in ...
... fluidity. Plant thylakoid membranes maintain high fluidity, even at relatively cold environmental temperatures, due to the ... Membrane lipids also form a matrix in which membrane proteins reside. Historically lipids were thought to merely serve a ... Cell membranes require high levels of cholesterol - typically an average of 20% cholesterol in the whole membrane, increasing ... Membrane lipids are a group of compounds (structurally similar to fats and oils) which form the double-layered surface of all ...
... affect a wide variety of membrane and cellular activities 1-5greatly stimulated interest in the study of membrane fluidity. It ... J.R. Riordan, Plasma membrane Mg2+ ATPase activity is inversely related to lipid fluidity in: Membrane Fluidity. Biophysical ... Interconnection of activities and membrane lipid fluidity in: Membrane Fluidity. Biophysical and Cellular Regulation, M. Kates ... Kimelberg H.K. (1985) Membrane Fluidity and Membrane Activities. In: Conti F., Blumberg W.E., de Gier J., Pocchiari F. (eds) ...
A great change in our picture of membranes has occurred in the last few years, and there is... ... An area of intense current interest in molecular and cell biology is the structure of biological membranes. ... Membrane Fluidity Membrane Fusion Molecular Mobility Integral Protein Cytoplasmic Surface These keywords were added by machine ... Singer S.J. (1975) Membrane Fluidity and Cellular Functions. In: Meints R.H., Davies E. (eds) Control Mechanisms in Development ...
Cells maintain membrane fluidity by regulating lipid saturation, but the molecular mechanisms of this homeoviscous adaptation ... Our data challenge the prevailing hypothesis that membrane fluidity serves as the measured variable for regulating lipid ... Rather, we show that Mga2 senses the molecular lipid-packing density in a defined region of the membrane. Our findings suggest ... that membrane property sensors have evolved remarkable sensitivities to highly specific aspects of membrane structure and ...
Membrane fluidity can be affected by a number of factors. One way to increase membrane fluidity is to heat up the membrane. ... In biology, membrane fluidity refers to the viscosity of the lipid bilayer of a cell membrane or a synthetic lipid membrane. ... The double bond increases fluidity. Membrane fluidity is also affected by cholesterol. Cholesterol can make the cell membrane ... This is one way they can adjust the fluidity of their membrane in response to their environment. Membrane fluidity is known to ...
... membrane viscosity for short range lateral diffusion has best been measured using lipid analog probes that, when interacting, ... Membrane fluidity or "membrane viscosity" for short range lateral diffusion has best been measured using lipid analog probes ... 372 nm) to excimer (EM 470 nm) fluorescence, a quantitative monitoring of the membrane fluidity can be attained. These ... Cellular Membrane Potential Assay Kit (Fluorometric - Orange) (ab176764) *Cellular Membrane Potential Assay Kit (Fluorometric ...
Phase transitions and fluidity characteristics of lipids and cell membranes.. Chapman D. ...
Increased fluidity in cell membranes could have a major impact on an ovarian cancer cells sensitivity to treatment using the ... Increased fluidity in cell membranes could have a major impact on an ovarian cancer cells sensitivity to treatment using the ... If a means to influence membrane fluidity could be achieved, it could enhance a drugs capability to cause DNA damage within ... Membrane fluidity influences sensitivity of ovarian cancer cell lines to auranofin. University of Plymouth ...
Why exactly does the cell membrane become more fluid in higher temperatures than lower? Does it have anything to do with the ...
Cytosine Arabinoside Transport and Membrane Fluidity in Acute Leukaemia Lead researcher. Dr J S Wiley (1984-1985, 1988), Dr W H ...
... on the fluidity of phosphatidylcholine vesicles. Changes in fluidity were assessed by changes in anisotropy values calculated ... Angiotensin II and related peptides alter liposomal membrane fluidity Biochem Mol Biol Int. 1998 Jan;44(1):203-9. doi: 10.1080/ ... These results suggest the possibility that these peptides may alter the fluidity of cell membranes by a direct action on the ... All three compounds produced an increase in membrane fluidity when localized inside the phosphatidylcholine vesicles. When ...
RESULTS Membrane fluidity was normal in the diabetic patients with good BG control but significantly lower in the two groups of ... OBJECTIVE To examine the factors that might alter the fluidity of erythrocyte membrane in insulin-dependent diabetes mellitus ( ... CONCLUSIONS The factors that most influence membrane fluidity in IDDM patients appear to be hyperglycemia and ketone bodies. ... Decreased Erythrocyte Membrane Fluidity in Poorly Controlled IDDM: Influence of ketone bodies. ...
To test this hypothesis, we used the membrane fluidity dye, di-4-ANEPPDHQ, to investigate membrane fluidity changes following ... Results in CHO cells show increased membrane fluidity with infrared light pulse exposure and this increased fluidity scales ... Short infrared laser pulses increase cell membrane fluidity Author(s): Alex J. Walsh; Jody C. Cantu; Bennett L. Ibey; Hope T. ... Altogether, these results demonstrate that infrared light induces a thermal gradient in cells that changes membrane fluidity. ...
Flotillin-mediated membrane fluidity controls peptidoglycan synthesis and MreB movement Final publishers version, 2 MB, PDF ... Loss of flotillins leads to a decrease in membrane fluidity that in turn leads to alterations in MreB dynamics and, as a ... Flotillin-mediated membrane fluidity controls peptidoglycan synthesis and MreB movement. Zielińska, A., Savietto, A., de Sousa ... Our data support a model in which flotillins are required for direct control of membrane fluidity rather than for the formation ...
Proteins do show lateral movement in the membrane, but i am not sure if that actually affects the fluidity... But this pdf file ... What are 4 factors that affect membrane fluidity? Ive looked in a textbook and havent been able to find 4. However, so far ... Membrane fluidity. Discussion of all aspects of cellular structure, physiology and communication. ... And presence of membrane carbohydrates and proteins. This is affect of the dispersion forces. ...
... only beginning to understand how eukaryotic cells sense and maintain the characteristic lipid compositions and bulk membrane ... The maintenance of a fluid lipid bilayer is key for membrane integrity and cell viability. We are ... One of the key factors determining membrane fluidity and phase behavior is the proportion of saturated and unsaturated acyl ... The maintenance of a fluid lipid bilayer is key for membrane integrity and cell viability. We are only beginning to understand ...
Increased fluidity in cell membranes could have a major impact on an ovarian cancer cells sensitivity to treatment using the ... Increased fluidity in cell membranes could have a major impact on an ovarian cancer cells sensitivity to treatment using the ... Membrane fluidity influences sensitivity of ovarian cancer cell lines to auranofin. New research has shown that increased ... If a means to influence membrane fluidity could be achieved, it could enhance a drugs capability to cause DNA damage within ...
I know that the higher the protein concentration in a plasma membrane, the higher the membrane fluidity. Is there a point at ... Protein Concentration vs Membrane Fluidity. Discussion of all aspects of biological molecules, biochemical processes and ... Im thinking there is a level at which if the membrane was supersaturated with integral or peripheral proteins the membrane ... which adding more proteins to this membrane will in fact decrease the fluidity? ...
Lymphocyte Activation and Membrane Fluidity in IGA Nephropathy. T R Ringrose, T H Thomas, J Kirby, R Wilkinson ... Lymphocyte Activation and Membrane Fluidity in IGA Nephropathy Message Subject (Your Name) has forwarded a page to you from ...
Correlations between the temperature dependence of chlorophyll fluorescence and the fluidity of thylakoid membranes. ... Correlations between the temperature dependence of chlorophyll fluorescence and the fluidity of thylakoid membranes. ...
Membrane Fluidity Is Regulated Cell Non-autonomously by Caenorhabditis elegans PAQR-2 and Its Mammalian Homolog AdipoR2. Rakesh ... Membrane Fluidity Is Regulated Cell Non-autonomously by Caenorhabditis elegans PAQR-2 and Its Mammalian Homolog AdipoR2. Rakesh ... Membrane Fluidity Is Regulated Cell Non-autonomously by Caenorhabditis elegans PAQR-2 and Its Mammalian Homolog AdipoR2. Rakesh ... In C. elegans, the PAQR-2 and IGLR-2 proteins act together as a plasma membrane sensor that responds to decreased fluidity by ...
Membrane Fluidity Gradient is Altered in Diabetic Mononuclear Leukocytes. P Tong, T Thomas, R Wilkinson ... Membrane Fluidity Gradient is Altered in Diabetic Mononuclear Leukocytes Message Subject (Your Name) has forwarded a page to ...
Associations between High-Sensitivity C-Reactive Protein and Membrane Fluidity of Red Blood Cells in Hypertensive Elderly Men: ... Kazushi Tsuda, "Associations between High-Sensitivity C-Reactive Protein and Membrane Fluidity of Red Blood Cells in ...
Membrane fluidity modulates cell function and we previously reported reduced membrane fluidity associated with hypersensitivity ... fluidity in platelet membranes from diabetic subjects is decreased. Reduced fluidity in platelet membranes from diabetic ... and could contribute to the decreased membrane fluidity in these platelets. We examined the relation among fluidity, ... Membrane fluidity is related to the extent of glycation of proteins, but not to alterations in the cholesterol to phospholipid ...
Influence of Cyclophosphamide, Oxygen Radicals and Dietary Vitamin-E on Lipid Composition and Fluidity of Lung Membranes. ... Patel studied how the normal composition and functioning of cell membranes in the lungs can be damaged by an anti-cancer drug ...
Estriol Improves Membrane Fluidity of Erythrocytes by the Nitric Oxide-Dependent Mechanism: an Electron Paramagnetic Resonance ... Abnormalities of cell-membrane fluidity in the pathogenesis of disease COOPER RA. ... Decreased membrane fluidity of erythrocytes and cultured vascular smooth muscle cells in spontaneously hypertensive rats: an ... Adrenomedullin and membrane fluidity of erythrocytes in mild essential hypertension TSUDA K. ...
Here, we show that caffeine interacts with unsaturated lipid membranes made of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine ... Partitioning of caffeine in lipid bilayers reduces membrane fluidity and increases membrane thickness A. Khondker, A. Dhaliwal ... Partitioning of caffeine in lipid bilayers reduces membrane fluidity and increases membrane thickness ... indicating a loss of membrane fluidity. These non-specific membrane interactions may increase the efficacy of analgesic drugs ...
... presumably by maintaining membrane fluidity. The fluidity of isolated cytoplasmic membranes of wild-type (SLCC53 and 10403S), ... We conclude that the fatty acid anteiso-C(15:0) imparts an essential fluidity to the L. monocytogenes membrane that permits ... Electron paramagnetic resonance studies of the membrane fluidity of the foodborne pathogenic psychrotroph Listeria ... tau(c) values over the temperature range of -7 degrees C to 50 degrees C were similar for the membranes of strains SLCC53 and ...
... of neuroblastoma cell growth by nisin is mediated by modulation of phase behavior and enhanced cell membrane fluidity ... of neuroblastoma cell growth by nisin is mediated by modulation of phase behavior and enhanced cell membrane fluidity A. Prince ... we find that nisin interaction enhances the fluidity and reduces the dipole potential of a neuroblastoma cell membrane model. ... The quantified compressibility modulus suggests that the changes in fluidity are predominantly driven by the nisin interaction ...
Role of lindane in membranes. Effects on membrane fluidity and activity of membrane-bound proteins Biosci Rep (June, 1994) ... Lindane-induced modifications to membrane lipid structure: Effect on membrane fluidity after subchronic treament M. T. ... resulted in an altered lipid pattern in rat ventral prostate membranes. An increase of membrane fluidity was also observed ... Influence of lindane on the fluidity of the rat ventral prostate membranes Biosci Rep (April, 1991) ...
Molecular dynamics simulations of a lipid bilayer and of hexadecane: an investigation of membrane fluidity ... Molecular dynamics simulations of a lipid bilayer and of hexadecane: an investigation of membrane fluidity ... Molecular dynamics simulations of a lipid bilayer and of hexadecane: an investigation of membrane fluidity ... Molecular dynamics simulations of a lipid bilayer and of hexadecane: an investigation of membrane fluidity ...
  • A great change in our picture of membranes has occurred in the last few years, and there is now fairly widespread acceptance of a model for the organization of the lipids and proteins of membranes called the "fluid mosaic model" (Singer and Nicolson, 1972). (springer.com)
  • In this model (Fig. 1) the proteins that are integral to the membrane (Singer, 1971) are proposed to be globular molecules which are partly embedded in the membrane lipid, and partly protrude from it. (springer.com)
  • The lipid, arranged largely as a bilayer, forms the matrix of the membrane, and since at physiological temperatures the lipid of most functional membranes is largely fluid, the integral proteins are in principle free to move about laterally and rapidly in the plane of the membrane. (springer.com)
  • Viscosity of the membrane can affect the rotation and diffusion of proteins and other bio-molecules within the membrane, there-by affecting the functions of these things. (wikipedia.org)
  • Also, a narrow annular lipid shell of membrane lipids in contact with integral membrane proteins have low fluidity compared to bulk lipids in biological membranes, as these lipid molecules stay stuck to surface of the protein macromolecules. (wikipedia.org)
  • Membrane fluidity determines how easily lipids and proteins can diffuse laterally in the plane of the membrane. (nature.com)
  • Class I sensors interrogate surface properties of cellular membranes, such as the surface charge and molecular packing density as reported for amphipathic lipid-packing sensor (ALPS) motif-containing proteins and other amphipathic helix-containing proteins 31 . (nature.com)
  • Current hypotheses suggest that flotillin proteins are required for the formation of complexes of membrane proteins including cell-wall synthetic proteins. (rug.nl)
  • However, so far I've been thinking: presence of cholesterol, temperature, composition of phospholipids (i.e. degree of saturation) and presence of membrane proteins/carbohydrates? (biology-online.org)
  • Proteins do show lateral movement in the membrane, but i am not sure if that actually affects the fluidity. (biology-online.org)
  • And presence of membrane carbohydrates and proteins. (biology-online.org)
  • Is there a point at which adding more proteins to this membrane will in fact decrease the fluidity? (biology-online.org)
  • I'm thinking there is a level at which if the membrane was supersaturated with integral or peripheral proteins the membrane would become less fluid. (biology-online.org)
  • In C. elegans, the PAQR-2 and IGLR-2 proteins act together as a plasma membrane sensor that responds to decreased fluidity by promoting fatty acid desaturation, hence restoring membrane fluidity. (genetics.org)
  • Membrane fluidity is related to the extent of glycation of proteins, but not to alterations in the cholesterol to phospholipid molar ratio in isola. (nih.gov)
  • Glycation of platelet membrane proteins is enhanced in diabetic subjects, and could contribute to the decreased membrane fluidity in these platelets. (nih.gov)
  • We examined the relation among fluidity, cholesterol/phospholipid molar ratio, and glycation of proteins in isolated platelet membranes from diabetic and control subjects. (nih.gov)
  • Proteins were glycated significantly more extensively in platelet membranes from diabetic subjects (25.5 +/- 0.9 nmol glucose/mg protein) than those from control subjects (21.0 +/- 0.6 nmol glucose/mg protein, p less than 0.001). (nih.gov)
  • Cell entry of enveloped viruses requires a wide-fusion-pore mechanism, involving clustering of fusion-activated proteins and fluidization of the plasma membrane and viral envelope. (portlandpress.com)
  • Our results demonstrate that increased membrane fluidity is not the sole cause of growth inhibition and that alcohols may also denature proteins within the membrane and cytosol, adversely affecting metabolism and decreasing cell growth. (asm.org)
  • Our results suggest that pathogenic Y. enterocolitica strains modulate lipid A acylation coordinately with expression of virulence proteins, thus reducing LPS packing and increasing outer membrane permeability. (asm.org)
  • Seminal plasma proteins regulate the association of lipids and proteins within detergent-resistant membrane domains of bovine spermatozoa. (semanticscholar.org)
  • Diffusion across a lipid membrane can occur spontaneously or be facilitated by integral membrane proteins. (openrepository.com)
  • Effect of the viral proteins on the fluidity of the membrane lipids in Sindbis virus. (semanticscholar.org)
  • Low temperature-induced lateral separation occurred between the intramembrane particles (integral proteins) and smooth patches (bilayer lipid) at temperatures between about 10 and -12 degrees in the outer membrane and between about -4 and -12 degrees in the inner, energy transducing membrane. (mysciencework.com)
  • Membrane proteins are also of two general types. (britannica.com)
  • Almost all intrinsic proteins contain special amino acid sequences, generally about 20- to 24-amino acids long, that extend through the internal regions of the cell membrane. (britannica.com)
  • In the popular fluid mosaic model for biomembranes, membrane proteins and other membrane-embedded molecules are in a two-dimensional fluid formed by the phospholipids. (schoolbag.info)
  • According to this model, membrane proteins and other membrane-embedded compounds are suspended in a two-dimensional (2-D) fluid formed by phospholipids. (schoolbag.info)
  • It allows, for example, free diffusion and equal distribution of new cell-synthesized lipids and proteins, lateral diffusion of proteins and other molecules in signaling events and other membrane reactions, membrane fusion (i.e., fusion of vesicles with organelles), separation of membranes during cell division, and so on. (schoolbag.info)
  • In contrast, the translational diffusion constants of lipids and proteins in membranes are characteristic of media with the viscosity over two orders of magnitude greater than that of oil, such as hexadecane. (schoolbag.info)
  • Membrane lipids and proteins participate in highly anisotropic translational and rotational diffusion motion. (schoolbag.info)
  • It is thus possible that the resistance mechanism that lowers the efficacy of doxorubicin, results from an increased density in membrane regions where the efflux proteins are present. (nature.com)
  • This can, in turn, lead to changes in cell signaling and the function of membrane proteins, e.g. transporters and ion channels 5 . (nature.com)
  • Among the most sophisticated functions of the plasma membrane is the ability to transmit signals by means of complex, integral proteins known as receptors. (oercommons.org)
  • The fluid mosaic model describes the structure of the plasma membrane as a mosaic of components-including phospholipids, cholesterol, proteins, and carbohydrates-that gives the membrane a fluid character. (oercommons.org)
  • Heterotetramerizations of aquaporin isoforms are considered as novel regulatory mechanisms for plasma membrane (PIPs) and tonoplast (TIPs) proteins, influencing their intrinsic permeability and trafficking dynamics in the adaptive response to changing environmental conditions. (frontiersin.org)
  • In fact, we have to consider an intrinsic membrane protein as a different type of protein, since the comprehensive function of intrinsic membrane proteins can only be understood in conjunction with their interactions with the lipid bilayer and other membrane proteins. (frontiersin.org)
  • If the length of the phospholipids decreased , then individually, other molecules within the cell membrane, such as transmembrane proteins, can move around more easily inside . (moosmosis.org)
  • If the molecules, proteins, and individual phospholipids are packed together so closely, this restricts internal molecule movement within the membrane. (moosmosis.org)
  • Cell membranes are made up of a complex structure of lipids and proteins that diffuse laterally giving rise to what we call membrane fluidity. (edu.sa)
  • During cellular development, such as neuronal differentiation, cell membranes undergo dramatic structural changes induced by proteins such as ARC and Cofilin among others in the case of synaptic modification. (edu.sa)
  • As major components of the selectively permeable bacterial membranes, lipids , though with relatively monotonic structures compared to membrane proteins, play significant roles in biochemical activities and stress tolerance. (kenyon.edu)
  • Sphingolipids, occurring primarily in nervous tissue, are thought to form cholesterol-rich domains within lipid bilayer membranes that may be important to the functions of some membrane proteins. (encyclopedia.com)
  • Thus membrane responses in the deletants were different to the parent strain, indicating that their fluidity regulation mechanisms were unbalanced by ablation of the activities of either of these membrane-associated proteins. (edu.au)
  • Plasma Membrane The plasma membrane is a very thin, continuous sheet of phospholipids and proteins that surrounds all living cells and separates them from their external environment. (bookrags.com)
  • Biological membranes, in the form of eukaryotic cell membranes , consist of a phospholipid bilayer with embedded, integral and peripheral proteins used in communication and transportation of chemicals and ions . (wikipedia.org)
  • The bulk of lipid in a cell membrane provides a fluid matrix for proteins to rotate and laterally diffuse for physiological functioning. (wikipedia.org)
  • Proteins are adapted to high membrane fluidity environment of lipid bilayer with the presence of an annular lipid shell , consisting of lipid molecules bound tightly to surface of integral membrane proteins . (wikipedia.org)
  • Certain proteins and lipids rest only on one surface of the membrane and not the other. (wikipedia.org)
  • This orientation is maintained during membrane trafficking - proteins, lipids, glycoconjugates facing the lumen of the ER and Golgi get expressed on the extracellular side of the plasma membrane. (wikipedia.org)
  • [7] Lipid rafts occur when lipid species and proteins aggregate in domains in the membrane. (wikipedia.org)
  • Integral proteins span the membranes with different domains on either side. (wikipedia.org)
  • Peripheral proteins are unlike integral proteins in that they hold weak interactions with the surface of the bilayer and can easily become dissociated from the membrane. (wikipedia.org)
  • [6] Peripheral proteins are located on only one face of a membrane and create membrane asymmetry. (wikipedia.org)
  • In biology, membrane fluidity refers to the viscosity of the lipid bilayer of a cell membrane or a synthetic lipid membrane. (wikipedia.org)
  • Losartan, are also known to alter membrane viscosity. (wikipedia.org)
  • We quantify it by measuring the diffusion coefficient of membrane lipids, which is inversely proportional to membrane viscosity. (nature.com)
  • Membrane fluidity or "membrane viscosity" for short range lateral diffusion has best been measured using lipid analog probes that, when interacting, exhibit changes in their spectral properties. (abcam.com)
  • Given that the calculated fast reorientational correlation times and the "microscopic" lateral diffusion of the lipids show excellent agreement with the experimental results, it is concluded that the apparently high viscosity of the membrane is more closely related to molecular interactions on the surface rather than in the interior. (sciencemag.org)
  • Adjusting the saturation degree of the fatty acids seems to play a major role in the homeostasis of viscosity of the cytoplasmic membrane of Acinetobacter calcoaceticus 69V, a feature that is critical for stabilising its apparatus for electron transport phosphorylation (ETP) against lipophilic attack by xenobiotics. (eurekamag.com)
  • It is much broader than the strict physical definition of fluidity as the reciprocal of viscosity in the case of isotropic liquids. (schoolbag.info)
  • Lipid-based approaches consider the intrinsic physical properties of the membrane, like fluidity, permeability, or viscosity, together with the lipid chemical composition, in regard to the interference with membrane protein function. (frontiersin.org)
  • the viscosity is called the fluidity, a measure of the ease of flow. (britannica.com)
  • LPS aggregates of bacteria grown in acidic or EGTA-supplemented broth took up more N -phenylnaphthylamine than LPS aggregates of bacteria grown in standard broth and also showed a marked increase in acyl chain fluidity which correlated with permeability, as determined by measurements obtained in the presence of hydrophobic dyes. (asm.org)
  • The changes in permeability, LPS acyl chain fluidity, and lipid A acylation in pathogenic Y. enterocolitica strains approximate the characteristics in Yersinia pseudotuberculosis and Yersinia pestis and suggest that there is a common outer membrane pattern associated with pathogenicity. (asm.org)
  • The most important parameters to quantify the notion of membrane fluidity are translational and rotational diffusion constants, order parameters (or tensors), packing, and permeability. (schoolbag.info)
  • In general, greater membrane fluidity is associated with higher diffusion rates, high permeability, lower ordering, and looser packing. (schoolbag.info)
  • From previous studies, the hopanoid lipids, as one of the essential components in biomembranes, contributes substantially to bacterial membrane permeability and fluidity, stress resistance, nitrogen fixation and bacterial associations with plants, etc. [7] The study of hopanoid lipid, as one of the new and frontier research, remains lots of unknown and interesting topics to study. (kenyon.edu)
  • The mechanical study suggested that BUE-induced liver toxicity was closely associated with necrosis detected by MTT and propidium iodide (PI) staining, via releasing lactate dehydrogenase (LDH), reducing the fluidity, and increasing the permeability of the cell membrane. (mdpi.com)
  • H.K. Kimelberg, The influence of membrane fluidity on the activity of membrane-bound enzymes, in: Cell Surface Reviews, G. Poste and G.L. Nicolson, eds. (springer.com)
  • H.K. Kimelberg, Protein-liposome interactions and their relevance to the structure and function of cell membranes, Molec. (springer.com)
  • An area of intense current interest in molecular and cell biology is the structure of biological membranes. (springer.com)
  • Cholesterol can make the cell membrane fluid as well as rigid. (wikipedia.org)
  • The biological analogue, 'lipid raft', is hypothesized to exist in cell membranes and perform biological functions. (wikipedia.org)
  • Phase transitions and fluidity characteristics of lipids and cell membranes. (nih.gov)
  • Increased fluidity in cell membranes could have a major impact on an ovarian cancer cell's sensitivity to treatment using the anti-rheumatic drug auranofin, research led by Plymouth University suggests. (eurekalert.org)
  • Now new research, published in Mutation Research - Genetic Toxicology and Environmental Mutagenesis , has shown that increased fluidity within the cell membrane can enhance the ability of auranofin to induce increased DNA damage and cellular oxidation in these cells. (eurekalert.org)
  • Cell membranes consist of a phospholipid bilayer, which protects a cell from its surroundings and controls the movement of substances. (eurekalert.org)
  • But in order to try and build resistance to this, cancer cells evolve by changing their genetic properties and cell membrane rigidity could be one of the confounding factors through which they become resistant to treatment. (eurekalert.org)
  • Previous research has shown that chemo-resistant cancer cells demonstrate greater rigidity of the cell membrane, with the current study suggesting that greater uptake of auranofin could be influenced by increased membrane fluidity. (eurekalert.org)
  • Why exactly does the cell membrane become more fluid in higher temperatures than lower? (physicsforums.com)
  • These results suggest the possibility that these peptides may alter the fluidity of cell membranes by a direct action on the phospholipid bilayer, which may in turn interfere with receptor-mediated effects. (nih.gov)
  • Therefore, this study tests the hypothesis that the fast thermal gradient induced in a cell by infrared light exposure causes a change in the membrane fluidity. (spie.org)
  • The maintenance of a fluid lipid bilayer is key for membrane integrity and cell viability. (ovid.com)
  • The full study - Linking genotoxicity and cytotoxicity with membrane fluidity: a comparative study in ovarian cancer cell lines following exposure to auranofin by Oommen, Dodd, Yiannakis, Moyeed and Jha - is published in Mutation Research - Genetic Toxicology and Environmental Mutagenesis, doi 10.1016/j.mrgentox.2016.09.003. (plymouth.ac.uk)
  • Here, we used mosaic analysis for paqr-2 and iglr-2 , and tissue-specific paqr- 2 expression, to show that membrane homeostasis is achieved cell non-autonomously. (genetics.org)
  • Specifically, we found that expression of paqr-2 in hypodermis, gonad sheath cells or intestine is sufficient to suppress systemic paqr-2 mutant phenotypes including: tail tip morphology, membrane fluidity in intestinal cells, cold and glucose intolerance, vitellogenin transport to the germ line, germ cell development and brood size. (genetics.org)
  • Finally, we show that the cell non-autonomous regulation of membrane homeostasis is conserved in human cells: HEK293 cells that express AdipoR2, a homolog of paqr-2 , are able to normalize membrane fluidity in distant cells where AdipoR2 has been silenced. (genetics.org)
  • Finally, using C. elegans mutants and siRNA against SCD in HEK 293 cells, we show that Δ9 desaturases are essential for the cell non-autonomous maintenance of membrane fluidity. (genetics.org)
  • Membrane fluidity modulates cell function and we previously reported reduced membrane fluidity associated with hypersensitivity to thrombin in intact platelets from diabetic subjects. (nih.gov)
  • Dr. Patel studied how the normal composition and functioning of cell membranes in the lungs can be damaged by an anti-cancer drug or by highly unstable metabolites of oxygen, and whether this might be prevented by vitamin E in the diet. (aicr.org)
  • However, the mechanism of nisin interaction with cancer cell membranes remains unexplored. (rsc.org)
  • Using potentiometric dye-based fluorescence and monolayer surface pressure-area isotherms we find that nisin interaction enhances the fluidity and reduces the dipole potential of a neuroblastoma cell membrane model. (rsc.org)
  • GL also inhibited cell-to-cell fusion induced by HIV-1 and HTLV-I (human T-cell leukaemia virus type I). However, when cells treated with 1 mg/ml GL were placed in GL-free medium, they showed increased susceptibility to HIV-1 infection and HTLV-I fusion due to enhancement of membrane fluidity. (portlandpress.com)
  • The membrane dependence of GL and GL removal experiments suggest that GL does affect the cell entry of viruses. (portlandpress.com)
  • Following attachment and adsorption of viral particles to specific receptors on host cells, enveloped viruses must enter the host cell by making a fusion pore, fusing their own lipid bilayer envelope coat with that of the plasma cell membrane. (portlandpress.com)
  • We quantitatively measured the fluidity of live cell plasma membranes and viral particle envelopes by ESR using 5-DSA (5-doxyl stearic acid) [ 15 , 16 ]. (portlandpress.com)
  • This system enables us to study the flow induced changes in plasma membrane of a representative cancer cell line HeLa as the function of imparted shear stress and importantly, cell-substrate adhesion strength. (eurekaselect.com)
  • We have shown while transient changes in membrane fluidity depend on the orientation of flow and are largely independent of cellsubstrate adhesion landscape, long term membrane fluidization is controlled by the cell-substrate adhesion strength that is represented by maximum traction stress that cell exerts on the microchannel wall. (eurekaselect.com)
  • Tamal Das, Tapas K. Maiti and Suman Chakraborty, "Flow Shear Induced Changes in Membrane Fluidity: Dependence on Cell- Substrate Adhesion Strength", Current Analytical Chemistry (2013) 9: 9. (eurekaselect.com)
  • Increased membrane fluidity, which causes cofactor leakage and loss of membrane potential, has long been documented as a cause for decreased cell growth during exposure to ethanol, butanol, and other alcohols. (asm.org)
  • We evaluated the red cell membrane dynamic property and the mean erythrocyte aggregation (MEA) in vascular atherosclerotic disease (VAD). (iospress.com)
  • The specific level of membrane fluidity is not uniform across the bacterial cell membrane. (bio-protocol.org)
  • Assessing changes in the overall membrane fluidity and formation of membrane microdomains is therefore pivotal to understand both the functional organization of the bacterial cell membrane as well as antibiotic mechanisms. (bio-protocol.org)
  • Cooper RA (1978) Influence of increased membrane cholesterol on membrane fluidity and cell function in human red blood cells. (springer.com)
  • Cell membranes are composed primarily of amphipathic lipids either in a single circular layer or as a bilayer in which all of the hydrophilic and hydrophobic groups face the same direction respectively. (openrepository.com)
  • Artificial lipid membranes that mimic some of the properties of natural cell membranes can be prepared on synthetic supports for use in membrane-based biosensors. (openrepository.com)
  • The lyotropic phase behaviour of model lipid systems that describe these modulations in lipid composition indicate that the average stored curvature elastic stress of the membrane is reduced on elongation of the cell, while the fluidity appears to be maintained. (nottingham.ac.uk)
  • These findings suggest that phospholipid metabolism is linked to the cell cycle and that changes in membrane composition can lower the energetic barrier to the succeeding stage of the cell cycle. (nottingham.ac.uk)
  • This therefore suggests a means by which bacteria can manage the physical properties of their membranes through the cell cycle. (nottingham.ac.uk)
  • The structure and function of cell membranes plays an important role in maintaining intracellular homeostasis through the activity of membrane enzymes, hormone receptors, and the transmembrane transport system. (conicyt.cl)
  • Ismaili A, Meddings JB, Ratnam S, Sherman PM. Modulation of host cell membrane fluidity: a novel mechanism for preventing bacterial adhesion. (sickkids.ca)
  • This type of lipid bilayer, formed by the self-assembly of lipid molecules, is the basic structure of the cell membrane . (britannica.com)
  • We also show limitations of the fluid mosaic model and discuss recent developments in membrane science that pertain to fluidity, such as evidence for compartmentalization of the biomembrane by the cell cytoskeleton. (schoolbag.info)
  • Despite doxorubicin being commonly used in chemotherapy there still remain significant holes in our knowledge regarding its delivery efficacy and an observed resistance mechanism that is postulated to involve the cell membrane. (nature.com)
  • there is also strong evidence suggesting that interaction with cell membranes plays a role in its activity 2 . (nature.com)
  • First, the drug must pass the selective barrier to entry into the cell that is the cell membrane and, finally, the nuclear membrane. (nature.com)
  • Drug-membrane interactions produce alterations in the physical properties of the cell membrane, as a result of the behavior of the drug within the membrane. (nature.com)
  • A cell's plasma membrane defines the cell, outlines its borders, and determines the nature of its interaction with its environment (see Table for a summary). (oercommons.org)
  • Therefore, an integrative approach to the relevance of the membrane-aquaporin interaction to different processes related to plant cell physiology is provided. (frontiersin.org)
  • One of the triumphs of cell biology during the decade from 1965 to 1975 was the recognition of the cell membrane as a fluid collection of amphiphilic molecules. (britannica.com)
  • What are Factors that Increase or Affect cell Membrane Fluidity? (moosmosis.org)
  • All cells have cell membranes that form as barriers between the outside extracellular side and the inside of the cell. (moosmosis.org)
  • Cell membranes are fluid, which means they are not always in the same shape. (moosmosis.org)
  • In general, shorter tail lengths of phospholipids, more unsaturated phospholipids, and less cholesterol in the cell membrane increases membrane fluidity. (moosmosis.org)
  • The longer the tails are, the less fluid the cell membrane is. (moosmosis.org)
  • The more phospholipids with double bonds, the more fluid the cell membrane is. (moosmosis.org)
  • When the environment is so cold, the cell membrane can freeze and stop moving, and that is bad. (moosmosis.org)
  • Thus, animals adapted to these frigid environments have more double-bonded phospholipids in their cell membranes, due to the double bonds making kinks and spacing out the individual phospholipids from freezing together so closely. (moosmosis.org)
  • More cholesterol in the cell membrane causes the membrane to become more rigid and less permeable to other molecules or ions in high temperatures. (moosmosis.org)
  • In higher temperatures, phospholipids and other cell membrane molecules are already moving wildly (See Section 5: Higher Temperatures). (moosmosis.org)
  • Cholesterols, shown as pink molecules in this diagram, take up large spaces in the cell membrane and thus reduce cell membrane fluidity in high temperatures. (moosmosis.org)
  • This is the same concept with the cell membrane. (moosmosis.org)
  • Higher temperatures cause an increase of fluidity in the cell membrane. (moosmosis.org)
  • In this study we used the generalized polarization (GP) property of fluorescent probe Laurdan using two-photon microscopy to determine membrane fluidity as a function of time and for various cell lines. (edu.sa)
  • This study sheds light on the involvement of membrane fluidity during neuronal differentiation and development of other cell lines. (edu.sa)
  • This review summarises work determining relationships among yeast membrane fluidity, cell physiology and environmental changes, utilising fluorescence spectroscopy and multi-photon microscopy. (edu.au)
  • Bacterial cell membrane. (kenyon.edu)
  • Phospholipids are the major lipid constituent in cell membranes, thus maintaining structural integrity between the cell and its environment and providing boundaries between compartments within the cell. (encyclopedia.com)
  • Everything you need to understand or teach Cell membrane . (bookrags.com)
  • Membrane Cell membranes or plasma membranes surround cells, separating the cytoplasm and organelles on the inside from the extracellular fluid on the outside. (bookrags.com)
  • Several cell organelles (mitochondria, en. (bookrags.com)
  • Membrane Structure Surrounding each cell within the nervous system is a highly complex lipid bilayer called a membrane formed by microscopic phospholipid molecules. (bookrags.com)
  • Prokaryotic Membrane Transport The ability of Prokaryotic microorganisms to move compounds into the cell, and to remove waste products of metabolism out of the cell, is crucial for the survival of the. (bookrags.com)
  • During oxidative stress membrane receptors and/or membrane lipid dynamics can be altered, leading to dysfunctional cell responses. (utmb.edu)
  • Our aim is to analyze membrane fluidity modifications and cell function under oxidative stress in LPS-activated macrophages. (utmb.edu)
  • However, oxidative stress induces rigidification of macrophage plasma membrane and inhibition of cell activation, which is evidenced by a decrease of TNFα secretion. (utmb.edu)
  • The effects of psychotropic drugs and local anaesthetics on the fluidity of Escherichia coli cell membranes were examined. (elsevier.com)
  • For the membranes surrounding cells, see cell membrane . (wikipedia.org)
  • The cell membranes are different from the isolating tissues formed by layers of cells, such as mucous membranes , basement membranes , and serous membranes . (wikipedia.org)
  • The aim of this research is to investigate the effects of paeoniflorin and menthol on the physiological function of Calu-3 cell membrane during the transport of puerarin. (bvsalud.org)
  • Calu-3 cell was used as the cell model to simulate nasal mucosa tissues, and the cell membrane fluidity, Na⁺-K⁺-ATPase activity and Ca²⁺-ATPase activity were detected by fluorescence recovery after photobleaching(FRAP) and ultramicro enzyme activity testing, in order to explore the mechanism of compatible drugs on promoting puerarin transport. (bvsalud.org)
  • The decrease of cell membrane fluidity by the non-steroidal anti-inflammatory drug Licofelone inhibits epidermal growth factor receptor signalling and triggers apoptosis in HCA-7 colon cancer cells. (unibo.it)
  • The ability to induce changes in cell membrane properties is nowadays considered an additional mechanism to explain the pharmacological effects of non-steroidal anti-inflammatory drugs (NSAIDs). (unibo.it)
  • Here, we provide evidence that, in HCA-7 cells, the pro-apoptotic effect of this drug relies, at least in part, on its ability to inhibit epidermal growth factor receptor (EGFR) signalling by a decrease of cell membrane fluidity. (unibo.it)
  • Indeed, Licofelone induced a relevant change in the relative proportions of some saturated, monounsaturated and polyunsaturated fatty acids constituting HCA-7 phospholipid fraction, and significantly increased the levels of cholesterol in HCA-7 cell membrane. (unibo.it)
  • Two-photon microscopy imaging of monolayer cells labeled with Laurdan, a membrane fluorescent probe, showed that tumor cell/fibroblast interaction enhanced fluidity of cancer cell membrane while neoplastic cells generally promoted an increase in fibroblast membrane packing density. (unicatt.it)
  • In particular, an overall pro-invasive effect of CAFs on both well- and poorly differentiated cancer cells was exteriorized by reduction of cell adhesion, induction of membrane fluidity, and migration velocity and directionality, along with a promotion of epithelial-mesenchymal transition. (unicatt.it)
  • The fatty acid proportion of 20:3ω6 and 20:4ω6 at 18.0°C and 20:3ω6 at 13.5°C (final) was significantly higher in fish fed L-ω3 diets and may have influenced the increased fluidity in liver cell membranes. (mun.ca)
  • The formation of planar supported lipid bilayers in specially designed Teflon wells on bare glass supports yields lateral diffusion coefficients (D) for 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhPC) which indicate a typical fluidity. (openrepository.com)
  • Herein, we investigated the effects of bamboo salt solution on supported lipid bilayers as a model system to characterize the interaction between lipid membranes and bamboo salt. (hanyang.ac.kr)
  • C.J. Livingstone and D. Schachter, Lipid dynamics and lipid-protein interactions in rat hepatocyte plasma membranes, J. Biol. (springer.com)
  • In recent years it has become obvious that protein complexes and lipids are not uniformly distributed within membranes. (rug.nl)
  • Our data support a model in which flotillins are required for direct control of membrane fluidity rather than for the formation of protein complexes via direct protein-protein interactions. (rug.nl)
  • I know that the higher the protein concentration in a plasma membrane, the higher the membrane fluidity. (biology-online.org)
  • Fluidities of HIV-1 envelopes were always lower than those of plasma membranes, since cholesterol/protein ratios of viral envelopes were higher than those of plasma membranes [ 15 , 17 , 18 ]. (portlandpress.com)
  • These findings are compatible with the view that the peripheral layer of the fundamental nuclear protein-framework, the so-called nuclear matrix, can modulate, inter alia, the lipid distribution and fluidity, respectively, in nuclear membranes. (eurekamag.com)
  • Knowles DW, Tilley L, Mohandas N, Chasis JA (1997) Erythrocyte membrane vacuolation: model for the molecular mechanism of protein sorting. (springer.com)
  • Loss of the F-BAR protein CIP4 reduces platelet production by impairing membrane-cytoskeleton remodeling. (sickkids.ca)
  • They theorized that the structure of the plasma membrane resembles a sandwich, with protein being analogous to the bread, and lipids being analogous to the filling. (oercommons.org)
  • The current knowledge of membrane components is rather complete, but the physical and structural aspects of the lipid-protein interactions are still under investigation and underline the complexity of the biological membrane as a whole. (frontiersin.org)
  • Two different approaches have been established to determine the protein and lipid molecules interaction in a membrane: lipid- and protein-based approaches ( Lee, 2011 ). (frontiersin.org)
  • It also outlines how determination of membrane fluidity by fluorescence spectroscopy and microscopy has provided insights into yeast responses to heat shock and heat and ethanol stress, the impact on membranes of the stress-protectant trehalose and roles of membrane-associated protein functions. (edu.au)
  • These membrane protein s have various functions and characteristics and catalyze different chemical reactions. (wikipedia.org)
  • 3) conditions of protein complexes of membrane cytoskeleton. (msu.ru)
  • As an important step towards a unifying membrane theory, we need to identify a set of membrane properties that are both minimally correlated and sufficient to uniquely describe the state of a bilayer. (nature.com)
  • When placed outside the vesicles, Ang II increased bilayer rigidity (decreased fluidity), whereas Ang and Ang I produced no effect. (nih.gov)
  • The purpose of this study was to elucidate how liposomal bilayer fluidity and barrier integrity affected the delivery of liposome-associated calcipotriol to the skin. (ovid.com)
  • This bilayer is the basis of the membranes of living cells. (britannica.com)
  • Such a fluid state allows free motion of constituents within the membrane bilayer and is extremely important for membrane function. (schoolbag.info)
  • The chemical composition and the physical characteristics of the lipid bilayer also influence many aspects of membrane aquaporins, including their functionality. (frontiersin.org)
  • In this lesson, we explain what factors affect or increase the fluidity of the plasma membrane or phospholipid bilayer. (moosmosis.org)
  • One-photon, time-resolved fluorescence anisotropy of Bdp-Chol decays as a triexponential in the lipid bilayer with an average rotational diffusion coefficient, lipid order parameter, and membrane fluidity that are sensitive to phase domains. (elsevier.com)
  • It was demonstrated that, with increasing ionic strength of the bamboo salt solution, the fluidity of a lipid bilayer increased. (hanyang.ac.kr)
  • A fluid membrane model of the phospholipid bilayer. (wikipedia.org)
  • [4] As seen in the fluid membrane model of the phospholipid bilayer, the outer leaflet and inner leaflet of the membrane are asymmetrical in their composition. (wikipedia.org)
  • Erythrocyte membrane fluidity was determined by fluorescence polarization using 6-(9-anthroyloxy stearic acid as fluorescent probe. (diabetesjournals.org)
  • For cellular fusion, actin-dependent energy transfer [ 10 - 12 ] may be associated with the assembly of the pre-fusion structures in the membrane, which probably facilitates or results in the lateral movement of molecules via fluidization of both plasma membranes. (portlandpress.com)
  • The fluidity of the membrane results from anisotropic rotation of phopholipid acyl chains and flip-flop movement of membrane molecules [ 13 , 14 ]. (portlandpress.com)
  • We are working to develop artificial membrane-based sensors for target molecules that should lead to more effective drug discovery and more efficient treatment and diagnosis of diseases. (openrepository.com)
  • The term ''membrane fluidity'' is a general concept, which refers to the ease of motion for molecules in the highly anisotropic membrane environment. (schoolbag.info)
  • Membrane fluidity, which describes the ease of movement for molecules in the membrane environment, is a general concept that lacks a precise definition. (schoolbag.info)
  • It includes lateral diffusion of molecules in the plane of the membrane, flexibility of acyl chains, "flip-flop" diffusion of molecules from one monolayer to the other, and so on. (schoolbag.info)
  • In terms of the solubility and the diffusion of small nonpolar molecules, the membrane behaves very much like an oil drop. (schoolbag.info)
  • This work represents a successful approach, combining experimental and computational studies of membrane based systems to unveil the behavior of drugs and candidate drug molecules. (nature.com)
  • A phospholipid that is covering the "aisle" with its longer tail length decreases the overall fluidity or movement of other molecules. (moosmosis.org)
  • Membrane Fluidity The membranes of bacteria function to give the bacterium its shape, allow the passage of molecules from the outside in and from the inside out, and to prevent the internal contents f. (bookrags.com)
  • To enable the membrane as a whole to grow evenly, half of the new phospholipid molecules then have to be transferred to the opposite monolayer. (wikipedia.org)
  • It indicates the way and the rate of motion of molecules in the membrane, and is inversely related to membrane microviscosity. (biomedcentral.com)
  • H.K. Kimelberg, Alterations in phospholipid-dependent (Na+K) ATPase activity due to lipid 'fluidity. (springer.com)
  • J.R. Riordan, Plasma membrane Mg2+ ATPase activity is inversely related to lipid fluidity in: Membrane Fluidity. (springer.com)
  • ESR using 5-doxylstearic acid as a spin label indicates a higher lipid fluidity in contracted than in expanded nuclear membranes. (eurekamag.com)
  • Observations that changes in membrane fluidity affect a wide variety of membrane and cellular activities 1-5 greatly stimulated interest in the study of membrane fluidity. (springer.com)
  • The discussion of this evidence could easily occupy my entire presentation, but I thought that in the context of this symposium it might be more useful to adopt the model as a working hypothesis of membrane structure and consider what it might imply about the mechanisms of a variety of important cellular functions and activities. (springer.com)
  • The bacterial plasma membrane is an important cellular compartment. (rug.nl)
  • Maintenance of membrane properties is an essential aspect of cellular homeostasis of which the regulatory mechanisms remain mostly uncharacterized. (genetics.org)
  • Rather, specialized microdomains associated with different cellular functions can exhibit fluidity values that significantly deviate from the average. (bio-protocol.org)
  • i.e., containing both a lipid-soluble and a water-soluble region) is basic to the role of lipids as building blocks of cellular membranes. (britannica.com)
  • It outlines studies of how membrane fluidity relates to growth phase, cellular physiology and nutrition (particularly, glucose and zinc status) and membrane lipid composition. (edu.au)
  • Phospholipids are the fundamental building blocks of cellular membranes and are the major part of surfactant , the film that occupies the air/liquid interfaces in the lung. (encyclopedia.com)
  • Dietary lipids also influence the fatty acid composition in various tissues including cellular membranes altering composition and function. (mun.ca)
  • The fatty acid composition and fluidity of gill phospholipids and hemocyte membranes of a eurytherrnal bivalve, Placopecten magellanicus, were investigated following a 10°C reduction in acclimation temperature. (mun.ca)
  • Abstract/Summary Cells maintain membrane fluidity by regulating lipid saturation, but the molecular mechanisms of this homeoviscous adaptation remain poorly understood. (ox.ac.uk)
  • abstract = "Synaptic membrane enriched fractions were prepared from 7 and 14 day and adult cortical nerve endings. (elsevier.com)
  • While the underlying mechanisms behind this have yet to be determined, it may be possible that hypercholesterolemia impairs the fluid shear stress (FSS) inactivation of neutrophils through the rigidifying effect of cholesterol on membrane fluidity. (uky.edu)
  • This useful hypothesis explained many phenomena that occur in model and biological membranes. (schoolbag.info)
  • More specifically, whether the fatty acids are saturated or unsaturated has an effect on membrane fluidity. (wikipedia.org)
  • Collectively, the results of this work demonstrate that processing of bamboo salt strongly affects its atomic composition and that the alkalinity of bamboo salt solutions contributes to its effect on membrane fluidity. (hanyang.ac.kr)
  • Loss of flotillins leads to a decrease in membrane fluidity that in turn leads to alterations in MreB dynamics and, as a consequence, in peptidoglycan synthesis. (rug.nl)
  • However, these shifts did not always result in a decrease in membrane fluidity or in greater tolerance of the organism to alcohol exposure. (asm.org)
  • Mitochondrial membranes in cardiac muscle from Antarctic notothenioid fishes vary in phospholipid composition and membrane fluidity. (uaf.edu)
  • In addition, OS increased the level of activated integrin α5 in lipid rafts through the regulation of membrane cholesterol and fluidity. (pnas.org)
  • Altogether, these data suggest that SigX is indirectly involved in CCR regulation, possibly via its effects on membrane integrity and fluidity. (inrs.ca)
  • We investigated the effects of angiotensinogen (Ang), angiotensin I (Ang I), and angiotensin II (Ang II) on the fluidity of phosphatidylcholine vesicles. (nih.gov)
  • All three compounds produced an increase in membrane fluidity when localized inside the phosphatidylcholine vesicles. (nih.gov)
  • In the present study, we documented the promising role of thyroid hormones status in animals in modulation of Na + -P i transport activity in intestinal brush border membrane vesicles (BBMV) which was accompanied with alterations in BBM lipid composition and fluidity. (springer.com)
  • Here, we use a new Bodipy-labeled cholesterol (Bdp-Chol) derivative to investigate membrane fluidity, lipid order, and partitioning in various lipid phases in giant unilamellar vesicles (GUVs) as a model system. (elsevier.com)
  • Changes in the fluidity of gill membranes were analyzed by incorporating 5-SASL into vesicles made from total gill phospholipid (PL). Membrane fluidity measurements showed that cold-acclimated scallop membranes were more fluid than those of warm-acclimated animals. (mun.ca)
  • J.S. Charnock, Effect of lipid composition on activity of membrane bound enzymes in: Advances in Experimental Medicine and Biology, S. Wolf and A.K. Murray, eds. (springer.com)
  • Download Membrane Fluidity In Biology. (octavachamberorchestra.com)
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  • Generally speaking, two principal mechanisms operate in the biology of membrane processes, such as membrane transport and permeation. (schoolbag.info)
  • Journal of Membrane Biology , 249 (6), 789-800. (utmb.edu)
  • In the present study, GL (glycyrrhizin) is reported to lower membrane fluidity, thus suppressing infection by HIV, influenza A virus and vesicular stomatitis virus, but not by poliovirus. (portlandpress.com)
  • One way to increase membrane fluidity is to heat up the membrane. (wikipedia.org)
  • Does cholesterol increase membrane fluidity? (moosmosis.org)
  • Cholesterol is a rigid molecule that can both decrease and increase membrane fluidity depending on the temperature of the membrane. (moosmosis.org)
  • To test this hypothesis, we used the membrane fluidity dye, di-4-ANEPPDHQ, to investigate membrane fluidity changes following infrared light exposure. (spie.org)
  • Membrane fluidity was assessed by fluorescence anisotropy measurements. (rjb.ro)
  • Altered lipid composition was a common response to alcohol exposure, with the most tolerant organisms maintaining a modestly fluid membrane. (asm.org)
  • Singer-Nicolson model of fluid membrane. (schoolbag.info)
  • Membrane fluidity is a key parameter of bacterial membranes that undergoes quick adaptation in response to environmental challenges and has recently emerged as an important factor in the antibacterial mechanism of membrane-targeting antibiotics. (bio-protocol.org)
  • Bacterial membranes have long been viewed as homogenous lipid bilayers following the classical fluid mosaic membrane model. (bio-protocol.org)
  • The most common simple hopanoid compounds in the bacterial membranes are diplopterol ( Figure 3 ) and diploptene ( Figure 5 ). (kenyon.edu)
  • Among 40 widely-found elongated hopanoids in the bacterial membranes, the most common hopanoids are aminobacterialhexanetriol and bacteriohopanetetrol . (kenyon.edu)
  • M.D. Houslay and R.W. Palmer, Changes in the form of Arrhenius plots of the activity of glucagon-stimulated adenylate cyclase and other hamster liver plasma-membrane enzymes occurring on hibernation, Biochem. (springer.com)
  • The loop inserts into the outer leaflet of the plasma membrane enabling trimer formation. (portlandpress.com)
  • The plasma membrane and the viral envelope are liquid or disordered under physiological conditions. (portlandpress.com)
  • Using the device, we are able to reveal novel shear induced immediate and late changes in the fluidity of apical plasma membrane. (eurekaselect.com)
  • Modification of the SU-8 3050 surface by plasma oxidation did not support membrane formation. (openrepository.com)
  • Spin-label studies on rat liver and heart plasma membranes: Do probe-probe interactions interfere with the measurement of membrane properties? (semanticscholar.org)
  • Thereby, a hypothesis for the vulnerability of doxorubicin to efflux through P-gp is its enhanced affinity for the ordered cholesterol rich regions of the plasma membrane. (nature.com)
  • The plasma membrane must be very flexible to allow certain cells, such as red blood cells and white blood cells, to change shape as they pass through narrow capillaries. (oercommons.org)
  • These are the more obvious functions of a plasma membrane. (oercommons.org)
  • In addition, the surface of the plasma membrane carries markers that allow cells to recognize one another, which is vital for tissue and organ formation during early development, and which later plays a role in the "self" versus "non-self" distinction of the immune response. (oercommons.org)
  • The existence of the plasma membrane was identified in the 1890s, and its chemical components were identified in 1915. (oercommons.org)
  • it was based on the "railroad track" appearance of the plasma membrane in early electron micrographs. (oercommons.org)
  • In the 1950s, advances in microscopy, notably transmission electron microscopy (TEM), allowed researchers to see that the core of the plasma membrane consisted of a double, rather than a single, layer. (oercommons.org)
  • A new model that better explains both the microscopic observations and the function of that plasma membrane was proposed by S.J. Singer and Garth L. Nicolson in 1972. (oercommons.org)
  • The model has evolved somewhat over time, but it still best accounts for the structure and functions of the plasma membrane as we now understand them. (oercommons.org)
  • Plasma membranes range from 5 to 10 nm in thickness. (oercommons.org)
  • For comparison, human red blood cells, visible via light microscopy, are approximately 8 µm wide, or approximately 1,000 times wider than a plasma membrane. (oercommons.org)
  • Properties and physiologic roles of the plasma membrane sodium-hydrogen exchanger. (jci.org)
  • It was shown that LPS activation causes fluidification of macrophage plasma membrane and production of TNFα. (utmb.edu)
  • In the plasma membrane, flippases transfer specific phospholipids selectively, so that different types become concentrated in each monolayer. (wikipedia.org)
  • Fluidity in mitochondrial membranes: thermotropic lateral tran. (mysciencework.com)
  • Fluidity in mitochondrial membranes: thermotropic lateral translational motion of intramembrane particles. (mysciencework.com)
  • The fracture faces of frozen rat liver mitochondria reveal that intramembrane particles can be induced to under go long-range lateral translational motion and aggregation, which parallel the appearance of large, particle-free smooth patches in the hydrophobic interior of the two mitochondrial membranes. (mysciencework.com)
  • Lower dose of Kh on day 1 after treatment induced higher mitochondrial membrane fluidity than control group. (conicyt.cl)
  • It facilitates the efflux of accumulated Ca2+, disrupts the potential of the membrane and causes mitochondrial lumps. (wikipedia.org)
  • Membrane fluidity can be measured with electron spin resonance, fluorescence, atomic force microscopy-based force spectroscopy, or deuterium nuclear magnetic resonance spectroscopy. (wikipedia.org)
  • Atomic force microscopy experiments can measure fluidity on synthetic or isolated patches of native membranes. (wikipedia.org)
  • Laurdan staining and two-photon confocal microscopy were applied to analyze the lens membrane fluidity of each group with different heating time. (arvojournals.org)
  • Membrane fluidity of individual living THP-1 macrophages was evaluated by the technique two-photon microscopy. (utmb.edu)
  • OBJECTIVE To examine the factors that might alter the fluidity of erythrocyte membrane in insulin-dependent diabetes mellitus (IDDM) patients. (diabetesjournals.org)
  • These alterations are reverted when membrane fluidity is restored by a chemical fluidizer. (rug.nl)
  • Taurine (TAU) and compounds representing a TAU analog (hypotaurine $=$ HYTAU) or homolog (aminomethanesulfonic acid $=$ AMSA, homotaurine $=$ HMTAU) were tested for their counteracting effects against alterations in erythrocyte (RBC) morphology, membrane fluidity and cytoskeletal spectrin distribution due to diabetes, alcoholism and diabetes-alcoholism in male Goto-Kakizaki rats (made diabetic with a high fat diet and alcoholic upon feeding on a flavored alcohol solution) and Wistar-Kyoto rats (serving as controls). (springer.com)
  • However, we detected alterations in membrane fluidity and ATPase activity. (conicyt.cl)
  • In this study we evaluate the alterations in membrane fluidity of blood platelets in patients with various entities of myeloid malignancies. (rjb.ro)
  • Reduced membrane fluidity in platelets from diabetic patients. (sickkids.ca)
  • M. Sinensky, K.P. Minneman and P.B. Molinoff, Increased membrane acyl chain ordering activates adenylate cyclase, J. Biol. (springer.com)
  • Role of serum 1,25-dihydroxyvitamin D3 levels and intestinal brush border membrane fluidity. (jci.org)
  • The fluidity of these membranes can be controlled by the lateral pressure applied, e.g. by the side walls of a box. (wikipedia.org)
  • How do cells, e.g., balance the need for maintaining membrane fluidity with the need to maintain organelle-specific lateral pressure profiles 20 ? (nature.com)
  • Probably, a contraction of the nuclear matrix's peripheral layer induces a contraction of the nuclear membranes, which in turn, leads to an isothermic lateral lipid segregation within nuclear membranes. (eurekamag.com)
  • Rather, we show that the signaling output of Mga2 correlates with the size of a single sensor residue in the transmembrane helix, which senses the lateral pressure and/or compressibility profile in a defined region of the membrane. (ox.ac.uk)
  • Lipid packing can influence the fluidity of the membrane. (wikipedia.org)
  • Influence of cholesterol/caveolin-1/caveolae homeostasis on membrane properties and substrate adhesion characteristics of adult human mesenchymal stem cells. (abcam.com)
  • If a means to influence membrane fluidity could be achieved, it could enhance a drug's capability to cause DNA damage within cancer cells and significantly influence treatment outcomes. (eurekalert.org)
  • CONCLUSIONS The factors that most influence membrane fluidity in IDDM patients appear to be hyperglycemia and ketone bodies. (diabetesjournals.org)
  • To evaluate the influence of α-crystallin racemization on lens membrane fluidity using the mild heating model based on lens epithelial cells (LECs). (arvojournals.org)
  • Lipid intermolecular hydrogen bonding: influence on structural organization and membrane function. (sickkids.ca)
  • Our results show that the presence of cholesterol induces a change in membrane structure and doesn't impair doxorubicin's membrane partitioning, but reduces drug's influence on membrane fluidity without directly interacting with it. (nature.com)
  • This response was correlated with an increase in the fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene (DPH) intercalated in the bilayers of liposomes prepared from the cells, indicating that the fluidity of their outer and cytoplasmic membranes fell as growth temperature increased. (eurekamag.com)
  • Here we describe how two fluorescent membrane dyes, laurdan and DiIC12, can be employed to assess membrane fluidity in living bacteria. (bio-protocol.org)
  • Bacteria can adapt their membrane fluidity by changing the ratios of branched/non-branched, unsaturated/saturated, and short-chain/long-chain fatty acids. (bio-protocol.org)
  • In the first group the ghosts were marked with DPH and the membrane microviscosity was calculated from the pol arization degree. (iospress.com)
  • Fluorescence anistropy of diphenyl hexatriene (rDPH) and microviscosity were significantly decreased in the intestinal BBM of Hyper-T rats and decreased in Hypo-T rats as compared to Eu-T rats which corroborated with the alteration in membrane fluidity in response to thyroid hormone status of animals. (springer.com)
  • d) The microviscosity of synaptic membranes, as measured by the fluorescence depolarization technique, increases during development. (elsevier.com)
  • H.K. Kimelberg and D. Papahadjopoulos, Phospholipid requirements for (Na++K+)-ATPase activity: Head-group specificity and fatty acid fluidity, Biochim. (springer.com)
  • To elucidate some of the subcellular effects of Kh toxicity, membrane fluidity and ATPase activities as hydrolytic and as proton-pumping activity were assessed in rat liver submitochondrial particles. (conicyt.cl)
  • Therefore, it was concluded that menthol had the abilit of promoting the transport and the mechanism might be related to increasing membrane fluidity and activating Ca²⁺-ATPase. (bvsalud.org)
  • In a group of subjects with vascular atherosclerotic disease (VAD) and in a group of normal controls we evaluated, at baseline and after in vitro chemotactic activation (prolonged for 5 and 15 min) with two stimulating agents (PMA and fMLP), the polymorphonuclear (PMN) filtration parameters, PMN me mbrane fluidity and PMN cytosolic Ca2+ content. (iospress.com)
  • Mahfoud R, Manis A, Lingwood CA. Fatty acid-dependent globotriaosyl ceramide receptor function in detergent resistant model membranes. (sickkids.ca)
  • Thus, we have studied doxorubicin's interaction with model membranes in a cholesterol rich, ordered environment and in liquid-disordered cholesterol poor environment. (nature.com)
  • Although these domains have been observed in model membranes, understanding cholesterol-lipid interactions at the molecular level, under controlled lipid mixing, remains a challenge. (elsevier.com)
  • In vitro, the addition of a flotillin increases membrane fluidity of liposomes. (rug.nl)
  • The liposomes' fluidity increased as the temperature at which it was measured was raised. (eurekamag.com)
  • Electron spin resonance measurements involve observing spin probe behaviour in the membrane. (wikipedia.org)
  • The fluidity of the lipids in the membrane of Sindbis virus was studied by electron paramagnetic resonance spectroscopy. (semanticscholar.org)
  • Membrane physical properties were measured by means of an electron spin resonance (ESR) spin-labeling technique, using 5-doxyl stearic acid (5-SASL) as a probe. (mun.ca)
  • In general, organisms tolerating the highest concentrations of alcohols maintained membrane fluidity after alcohol exposure, whereas organisms that increased membrane rigidity were less tolerant. (asm.org)
  • The lipid membrane, as a whole, shows a unique combination of fluidity and rigidity. (schoolbag.info)
  • Our data challenge the prevailing hypothesis that membrane fluidity serves as the measured variable for regulating lipid saturation. (nature.com)
  • The observed changes in cholesterol and phospholipid composition are also consistent with the hypothesis that lindane perturbs the lipid matrix of membranes, possibly inducing complex compensatory changes in the membrane lipid composition. (portlandpress.com)
  • Tovuu, A., Zulfugarov, I. S. and Lee, C.-H. (2013), Correlations between the temperature dependence of chlorophyll fluorescence and the fluidity of thylakoid membranes. (wiley.com)
  • Changes in fluidity were assessed by changes in anisotropy values calculated from fluorescence polarization measurements. (nih.gov)
  • The quantified compressibility modulus suggests that the changes in fluidity are predominantly driven by the nisin interaction with the non-raft like regions. (rsc.org)
  • The parent had negligible membrane fluidity response to glucose while the hsp30 and ole1 deletants both showed marked changes in fluidity on glucose addition above (0.5% w/v) or below (0.1%) the catabolite repression threshold. (edu.au)
  • We assessed relationships between fluidity and physiological parameters during aerobic and anaerobic batch culture, as well as membrane responses to glucose availability, determining progressive fluidity changes with fluorescent membrane probes. (edu.au)
  • Jain SK, McVie R, Duett J, Herbst JJ (1989) Erythrocyte membrane lipid peroxidation and glycosylated hemoglobin in diabetes. (springer.com)
  • [7] Erythrocyte membrane plays a crucial role in blood clotting. (wikipedia.org)
  • The double bond increases fluidity. (wikipedia.org)
  • However, more cholesterol increases fluidity in low temperatures. (moosmosis.org)