Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.
Positively charged atoms, radicals or groups of atoms with a valence of plus 2, which travel to the cathode or negative pole during electrolysis.
Positively charged atoms, radicals or group of atoms with a valence of plus 1, which travel to the cathode or negative pole during electrolysis.
A family of proteins involved in the transport of organic cations. They play an important role in the elimination of a variety of endogenous substances, xenobiotics, and their metabolites from the body.
An organic cation transporter found in kidney. It is localized to the basal lateral membrane and is likely to be involved in the renal secretion of organic cations.
A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
A subgroup of TRP cation channels named after melastatin protein. They have the TRP domain but lack ANKYRIN repeats. Enzyme domains in the C-terminus leads to them being called chanzymes.
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.
A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.
A subgroup of TRP cation channels that contain 3-4 ANKYRIN REPEAT DOMAINS and a conserved C-terminal domain. Members are highly expressed in the CENTRAL NERVOUS SYSTEM. Selectivity for calcium over sodium ranges from 0.5 to 10.
Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.
An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
Membrane proteins whose primary function is to facilitate the transport of positively charged molecules (cations) across a biological membrane.
The rate dynamics in chemical or physical systems.
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)
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).
An element that is an alkali metal. It has an atomic symbol Rb, atomic number 37, and atomic weight 85.47. It is used as a chemical reagent and in the manufacture of photoelectric cells.
An element of the alkaline earth family of metals. It has the atomic symbol Sr, atomic number 38, and atomic weight 87.62.
An element in the alkali metals family. It has the atomic symbol Li, atomic number 3, and atomic weight [6.938; 6.997]. Salts of lithium are used in treating BIPOLAR DISORDER.
A subgroup of TRP cation channels named after vanilloid receptor. They are very sensitive to TEMPERATURE and hot spicy food and CAPSAICIN. They have the TRP domain and ANKYRIN repeats. Selectivity for CALCIUM over SODIUM ranges from 3 to 100 fold.
High molecular weight insoluble polymers which contain functional anionic groups that are capable of undergoing exchange reactions with cations.
A member of the alkali metals. It has an atomic symbol Cs, atomic number 50, and atomic weight 132.91. Cesium has many industrial applications, including the construction of atomic clocks based on its atomic vibrational frequency.
Metals that constitute group 1(formerly group Ia) of the periodic table. They are the most strongly electropositive of the metals. Note that HYDROGEN is not considered an alkali metal even though it falls under the group 1 heading in the periodic table.
The movement of ions across energy-transducing cell membranes. Transport can be active, passive or facilitated. Ions may travel by themselves (uniport), or as a group of two or more ions in the same (symport) or opposite (antiport) directions.
A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.
A subgroup of cyclic nucleotide-regulated ION CHANNELS within the superfamily of pore-loop cation channels. They are expressed in OLFACTORY NERVE cilia and in PHOTORECEPTOR CELLS and some PLANTS.
An element of the alkaline earth group of metals. It has an atomic symbol Ba, atomic number 56, and atomic weight 138. All of its acid-soluble salts are poisonous.
An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.
The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.
An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.
Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.
A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.
The ability of a substrate to allow the passage of ELECTRONS.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
An anthranilic acid derivative with analgesic, anti-inflammatory, and antipyretic properties. It is used in musculoskeletal and joint disorders and administered by mouth and topically. (From Martindale, The Extra Pharmacopoeia, 30th ed, p16)
Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)
Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Lanthanum. The prototypical element in the rare earth family of metals. It has the atomic symbol La, atomic number 57, and atomic weight 138.91. Lanthanide ion is used in experimental biology as a calcium antagonist; lanthanum oxide improves the optical properties of glass.
A trace element that is a component of vitamin B12. It has the atomic symbol Co, atomic number 27, and atomic weight 58.93. It is used in nuclear weapons, alloys, and pigments. Deficiency in animals leads to anemia; its excess in humans can lead to erythrocytosis.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
A potassium-selective ion channel blocker. (From J Gen Phys 1994;104(1):173-90)
A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
A group of membrane transport proteins that transport biogenic amine derivatives of catechol across the PLASMA MEMBRANE. Catecholamine plasma membrane transporter proteins regulate neural transmission as well as catecholamine metabolism and recycling.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.
The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.
The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.
Substances produced from the reaction between acids and bases; compounds consisting of a metal (positive) and nonmetal (negative) radical. (Grant & Hackh's Chemical Dictionary, 5th ed)
Gadolinium. An element of the rare earth family of metals. It has the atomic symbol Gd, atomic number 64, and atomic weight 157.25. Its oxide is used in the control rods of some nuclear reactors.
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.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A subgroup of TRP cation channels that are widely expressed in various cell types. Defects are associated with POLYCYSTIC KIDNEY DISEASES.
Membrane transporters that co-transport two or more dissimilar molecules in the opposite direction across a membrane. Usually the transport of one ion or molecule is against its electrochemical gradient and is "powered" by the movement of another ion or molecule with its electrochemical gradient.
A chelating agent relatively more specific for calcium and less toxic than EDETIC ACID.
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.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
An element with atomic symbol Cd, atomic number 48, and atomic weight 114. It is a metal and ingestion will lead to CADMIUM POISONING.
A group of elements that include SCANDIUM; YTTRIUM; and the LANTHANOID SERIES ELEMENTS. Historically, the rare earth metals got their name from the fact that they were never found in their pure elemental form, but as an oxide. In addition they were very difficult to purify. They are not truly rare and comprise about 25% of the metals in the earth's crust.
Metals that constitute the group 2 (formerly group IIa) of the periodic table.
Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.
A cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like DIGITALIS. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-EXCHANGING ATPASE.
A ubiquitous sodium salt that is commonly used to season food.
A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.
A heavy, bluish white metal, atomic number 81, atomic weight [204.382; 204.385], symbol Tl.
Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).
A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning.
An organic amine proton acceptor. It is used in the synthesis of surface-active agents and pharmaceuticals; as an emulsifying agent for cosmetic creams and lotions, mineral oil and paraffin wax emulsions, as a biological buffer, and used as an alkalizer. (From Merck, 11th ed; Martindale, The Extra Pharmacopoeia, 30th ed, p1424)
Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.
Established cell cultures that have the potential to propagate indefinitely.
Chemicals that bind to and remove ions from solutions. Many chelating agents function through the formation of COORDINATION COMPLEXES with METALS.
Reversible chemical reaction between a solid, often one of the ION EXCHANGE RESINS, and a fluid whereby ions may be exchanged from one substance to another. This technique is used in water purification, in research, and in industry.
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.
A broad group of eukaryotic six-transmembrane cation channels that are classified by sequence homology because their functional involvement with SENSATION is varied. They have only weak voltage sensitivity and ion selectivity. They are named after a DROSOPHILA mutant that displayed transient receptor potentials in response to light. A 25-amino-acid motif containing a TRP box (EWKFAR) just C-terminal to S6 is found in TRPC, TRPV and TRPM subgroups. ANKYRIN repeats are found in TRPC, TRPV & TRPN subgroups. Some are functionally associated with TYROSINE KINASE or TYPE C PHOSPHOLIPASES.
Chemical agents that increase the permeability of biological or artificial lipid membranes to specific ions. Most ionophores are relatively small organic molecules that act as mobile carriers within membranes or coalesce to form ion permeable channels across membranes. Many are antibiotics, and many act as uncoupling agents by short-circuiting the proton gradient across mitochondrial membranes.
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.
An active neurotoxic metabolite of 1-METHYL-4-PHENYL-1,2,3,6-TETRAHYDROPYRIDINE. The compound reduces dopamine levels, inhibits the biosynthesis of catecholamines, depletes cardiac norepinephrine and inactivates tyrosine hydroxylase. These and other toxic effects lead to cessation of oxidative phosphorylation, ATP depletion, and cell death. The compound, which is related to PARAQUAT, has also been used as an herbicide.
A group of peptide antibiotics from BACILLUS brevis. Gramicidin C or S is a cyclic, ten-amino acid polypeptide and gramicidins A, B, D are linear. Gramicidin is one of the two principal components of TYROTHRICIN.
Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
A cyclododecadepsipeptide ionophore antibiotic produced by Streptomyces fulvissimus and related to the enniatins. It is composed of 3 moles each of L-valine, D-alpha-hydroxyisovaleric acid, D-valine, and L-lactic acid linked alternately to form a 36-membered ring. (From Merck Index, 11th ed) Valinomycin is a potassium selective ionophore and is commonly used as a tool in biochemical studies.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Transport proteins that carry specific substances in the blood or across cell membranes.
A pyrazine compound inhibiting SODIUM reabsorption through SODIUM CHANNELS in renal EPITHELIAL CELLS. This inhibition creates a negative potential in the luminal membranes of principal cells, located in the distal convoluted tubule and collecting duct. Negative potential reduces secretion of potassium and hydrogen ions. Amiloride is used in conjunction with DIURETICS to spare POTASSIUM loss. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p705)
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
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 study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Stable cesium atoms that have the same atomic number as the element cesium, but differ in atomic weight. Cs-133 is a naturally occurring isotope.
Ions with the suffix -onium, indicating cations with coordination number 4 of the type RxA+ which are analogous to QUATERNARY AMMONIUM COMPOUNDS (H4N+). Ions include phosphonium R4P+, oxonium R3O+, sulfonium R3S+, chloronium R2Cl+
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
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.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
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.
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)
A subgroup of cyclic nucleotide-regulated ION CHANNELS of the superfamily of pore-loop cation channels that are opened by hyperpolarization rather than depolarization. The ion conducting pore passes SODIUM, CALCIUM, and POTASSIUM cations with a preference for potassium.
Proteins prepared by recombinant DNA technology.
Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.
A polyamine formed from putrescine. It is found in almost all tissues in association with nucleic acids. It is found as a cation at all pH values, and is thought to help stabilize some membranes and nucleic acid structures. It is a precursor of spermine.
The accumulation of an electric charge on a object
A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.
A class of sodium-independent nucleoside transporters that mediate the facilitative transport of NUCLEOSIDES.
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.
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.
Measurement of the intensity and quality of fluorescence.
A biogenic polyamine formed from spermidine. It is found in a wide variety of organisms and tissues and is an essential growth factor in some bacteria. It is found as a polycation at all pH values. Spermine is associated with nucleic acids, particularly in viruses, and is thought to stabilize the helical structure.
Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.
A basic constituent of lecithin that is found in many plants and animal organs. It is important as a precursor of acetylcholine, as a methyl donor in various metabolic processes, and in lipid metabolism.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Organic compounds that contain phosphorus as an integral part of the molecule. Included under this heading is broad array of synthetic compounds that are used as PESTICIDES and DRUGS.
The physical characteristics and processes of biological systems.
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
An ionophorous, polyether antibiotic from Streptomyces chartreusensis. It binds and transports CALCIUM and other divalent cations across membranes and uncouples oxidative phosphorylation while inhibiting ATPase of rat liver mitochondria. The substance is used mostly as a biochemical tool to study the role of divalent cations in various biological systems.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A class of drugs that act by selective inhibition of calcium influx through cellular membranes.
The sum of the weight of all the atoms in a molecule.
Cationic ionophore antibiotic obtained from Streptomyces lasaliensis that, among other effects, dissociates the calcium fluxes in muscle fibers. It is used as a coccidiostat, especially in poultry.
An anionic compound that is used as a reagent for determination of potassium, ammonium, rubidium, and cesium ions. It also uncouples oxidative phosphorylation and forms complexes with biological materials, and is used in biological assays.
Elements of limited time intervals, contributing to particular results or situations.
Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.
A purinergic P2X neurotransmitter receptor that plays a role in pain sensation signaling and regulation of inflammatory processes.
The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.
A colloidal, hydrated aluminum silicate that swells 12 times its dry size when added to water.
Inorganic or organic oxy acids of sulfur which contain the RSO2(OH) radical.
1-Deoxy-1-(methylamino)-D-glucitol. A derivative of sorbitol in which the hydroxyl group in position 1 is replaced by a methylamino group. Often used in conjunction with iodinated organic compounds as contrast medium.
Stable potassium atoms that have the same atomic number as the element potassium, but differ in atomic weight. K-41 is a stable potassium isotope.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Stable sodium atoms that have the same atomic number as the element sodium, but differ in atomic weight. Na-23 is a stable sodium isotope.
Agents that affect ION PUMPS; ION CHANNELS; ABC TRANSPORTERS; and other MEMBRANE TRANSPORT PROTEINS.
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.
Membrane proteins that allow the exchange of hydrogen ions for potassium ions across the cellular membrane. The action of these antiporters influences intracellular pH and potassium ion homeostasis.
High molecular weight, insoluble polymers which contain functional groups that are capable of undergoing exchange reactions (ION EXCHANGE) with either cations or anions.
A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.
An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
A polyether antibiotic which affects ion transport and ATPase activity in mitochondria. It is produced by Streptomyces hygroscopicus. (From Merck Index, 11th ed)
Inorganic salts of phosphoric acid.
A class of cell surface receptors for PURINES that prefer ATP or ADP over ADENOSINE. P2 purinergic receptors are widespread in the periphery and in the central and peripheral nervous system.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.
The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.
Salts of hydrobromic acid, HBr, with the bromine atom in the 1- oxidation state. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.
A disaccharide consisting of one galactose and one glucose moiety in an alpha (1-6) glycosidic linkage.
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
Hemolytic anemia due to various intrinsic defects of the erythrocyte.
Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
An inorganic dye used in microscopy for differential staining and as a diagnostic reagent. In research this compound is used to study changes in cytoplasmic concentrations of calcium. Ruthenium red inhibits calcium transport through membrane channels.
A widely distributed purinergic P2X receptor subtype that plays a role in pain sensation. P2X4 receptors found on MICROGLIA cells may also play a role in the mediation of allodynia-related NEUROPATHIC PAIN.
Contractile tissue that produces movement in animals.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
A silver metallic element that exists as a liquid at room temperature. It has the atomic symbol Hg (from hydrargyrum, liquid silver), atomic number 80, and atomic weight 200.59. Mercury is used in many industrial applications and its salts have been employed therapeutically as purgatives, antisyphilitics, disinfectants, and astringents. It can be absorbed through the skin and mucous membranes which leads to MERCURY POISONING. Because of its toxicity, the clinical use of mercury and mercurials is diminishing.
The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.
A fluorescent calcium chelating agent which is used to study intracellular calcium in tissues.
Proteins found in any species of bacterium.
A family of proton-gated sodium channels that are primarily expressed in neuronal tissue. They are AMILORIDE-sensitive and are implicated in the signaling of a variety of neurological stimuli, most notably that of pain in response to acidic conditions.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
A general class of integral membrane proteins that transport ions across a membrane against an electrochemical gradient.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
Terbium. An element of the rare earth family of metals. It has the atomic symbol Tb, atomic number 65, and atomic weight 158.92.
Signal transduction mechanisms whereby calcium mobilization (from outside the cell or from intracellular storage pools) to the cytoplasm is triggered by external stimuli. Calcium signals are often seen to propagate as waves, oscillations, spikes, sparks, or puffs. The calcium acts as an intracellular messenger by activating calcium-responsive proteins.
A constituent of STRIATED MUSCLE and LIVER. It is an amino acid derivative and an essential cofactor for fatty acid metabolism.
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.
An inhibitor of anion conductance including band 3-mediated anion transport.
The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Unstable isotopes of sodium that decay or disintegrate emitting radiation. Na atoms with atomic weights 20-22 and 24-26 are radioactive sodium isotopes.
A plasma membrane exchange glycoprotein transporter that functions in intracellular pH regulation, cell volume regulation, and cellular response to many different hormones and mitogens.
Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.
Unstable isotopes of rubidium that decay or disintegrate emitting radiation. Rb atoms with atomic weights 79-84, and 86-95 are radioactive rubidium isotopes.
Phenolic metacyclophanes derived from condensation of PHENOLS and ALDEHYDES. The name derives from the vase-like molecular structures. A bracketed [n] indicates the number of aromatic rings.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A sesquiterpene lactone found in roots of THAPSIA. It inhibits CA(2+)-TRANSPORTING ATPASE mediated uptake of CALCIUM into SARCOPLASMIC RETICULUM.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The process of cleaving a chemical compound by the addition of a molecule of water.
Substances that dissociate into two or more ions, to some extent, in water. Solutions of electrolytes thus conduct an electric current and can be decomposed by it (ELECTROLYSIS). (Grant & Hackh's Chemical Dictionary, 5th ed)
A subclass of purinergic P2 receptors that signal by means of a ligand-gated ion channel. They are comprised of three P2X subunits which can be identical (homotrimeric form) or dissimilar (heterotrimeric form).
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
The characteristic three-dimensional shape of a molecule.

Bound forms of Ca taken up by the synaptic plasma membrane. (1/762)

Temperature dependent Ca-binding by the synaptic plasma membrane was increased in the presence of ATP and Mg++. Apparent Km for ATP was about 2.8 X 10(-5) M and optimal concentration of Mg++ was 2 mM in the presence of 2 mM ATP. After preincubation with nonradioactive Ca++, ATP and Mg++ to attain a steady state, addition of 45Ca resulted in remarkable labelling of the membrane, indicating rapid turnover of most of the membrane bound Ca. The presence of oxalate (60 mM) greatly increased Ca up-take on prolonged incubation. The Ca uptake in presence and absence of oxalate had similar substrate specificity and was similarly influenced by various monovalent cations. Furthermore, activities for Ca-uptake in the presence and absence of oxalate could not be separated by sucrose density gradient centrifugation of the synaptic plasma membrane fraction. Accordingly, it was considered that Ca++ in the medium was taken up by surface of the membrane, ATP- and temperature-dependently and then transferred into a cavity where the Ca-oxalate complex is formed.  (+info)

Selectivity and permeation in calcium release channel of cardiac muscle: alkali metal ions. (2/762)

Current was measured from single open channels of the calcium release channel (CRC) of cardiac sarcoplasmic reticulum (over the range +/-180 mV) in pure and mixed solutions (e.g., biionic conditions) of the alkali metal ions Li+, K+, Na+, Rb+, Cs+, ranging in concentration from 25 mM to 2 M. The current-voltage (I-V) relations were analyzed by an extension of the Poisson-Nernst-Planck (PNP) formulation of electrodiffusion, which includes local chemical interaction described by an offset in chemical potential, which likely reflects the difference in dehydration/solvation/rehydration energies in the entry/exit steps of permeation. The theory fits all of the data with few adjustable parameters: the diffusion coefficient of each ion species, the average effective charge distribution on the wall of the pore, and an offset in chemical potential for lithium and sodium ions. In particular, the theory explains the discrepancy between "selectivities" defined by conductance sequence and "selectivities" determined by the permeability ratios (i.e., reversal potentials) in biionic conditions. The extended PNP formulation seems to offer a successful combined treatment of selectivity and permeation. Conductance selectivity in this channel arises mostly from friction: different species of ions have different diffusion coefficients in the channel. Permeability selectivity of an ion is determined by its electrochemical potential gradient and local chemical interaction with the channel. Neither selectivity (in CRC) seems to involve different electrostatic interaction of different ions with the channel protein, even though the ions have widely varying diameters.  (+info)

Cloning and expression of the algL gene, encoding the Azotobacter chroococcum alginate lyase: purification and characterization of the enzyme. (3/762)

The alginate lyase-encoding gene (algL) of Azotobacter chroococcum was localized to a 3.1-kb EcoRI DNA fragment that revealed an open reading frame of 1,116 bp. This open reading frame encodes a protein of 42.98 kDa, in agreement with the value previously reported by us for this protein. The deduced protein has a potential N-terminal signal peptide that is consistent with its proposed periplasmic location. The analysis of the deduced amino acid sequence indicated that the gene sequence has a high homology (90% identity) to the Azotobacter vinelandii gene sequence, which has very recently been deposited in the GenBank database, and that it has 64% identity to the Pseudomonas aeruginosa gene sequence but that it has rather low homology (15 to 22% identity) to the gene sequences encoding alginate lyase in other bacteria. The A. chroococcum AlgL protein was overproduced in Escherichia coli and purified to electrophoretic homogeneity in a two-step chromatography procedure on hydroxyapatite and phenyl-Sepharose. The kinetic and molecular parameters of the recombinant alginate lyase are similar to those found for the native enzyme.  (+info)

Ion binding and permeation through the lepidopteran amino acid transporter KAAT1 expressed in Xenopus oocytes. (4/762)

1. The transient and steady-state currents induced by voltage jumps in Xenopus oocytes expressing the lepidopteran amino acid co-transporter KAAT1 have been investigated by two-electrode voltage clamp. 2. KAAT1-expressing oocytes exhibited membrane currents larger than controls even in the absence of amino acid substrate (uncoupled current). The selectivity order of this uncoupled current was Li+ > Na+ approximately Rb+ approximately K+ > Cs+; in contrast, the permeability order in non-injected oocytes was Rb+ > K+ > Cs+ > Na+ > Li+. 3. KAAT1-expressing oocytes gave rise to 'pre-steady-state currents' in the absence of amino acid. The characteristics of the charge movement differed according to the bathing ion: the curves in K+ were strongly shifted (> 100 mV) towards more negative potentials compared with those in Na+, while in tetramethylammonium (TMA+) no charge movement was detected. 4. The charge-voltage (Q-V) relationship in Na+ could be fitted by a Boltzmann equation having V of -69 +/- 1 mV and slope factor of 26 +/- 1 mV; lowering the Na+ concentrations shifted the Q-V relationship to more negative potentials; the curves could be described by a generalized Hill equation with a coefficient of 1.6, suggesting two binding sites. The maximal movable charge (Qmax) in Na+, 3 days after injection, was in the range 2.5-10 nC. 5. Addition of the transported substrate leucine increased the steady-state carrier current, the increase being larger in high K+ compared with high Na+ solution; in these conditions the charge movement disappeared. 6. Applying Eyring rate theory, the energy profile of the transporter in the absence of organic substrate included a very high external energy barrier (25.8 RT units) followed by a rather deep well (1.8 RT units).  (+info)

A single point mutation in the pore region of the epithelial Na+ channel changes ion selectivity by modifying molecular sieving. (5/762)

The epithelial Na+ channel (ENaC) belongs to a new class of channel proteins called the ENaC/DEG superfamily involved in epithelial Na+ transport, mechanotransduction, and neurotransmission. The role of ENaC in Na+ homeostasis and in the control of blood pressure has been demonstrated recently by the identification of mutations in ENaC beta and gamma subunits causing hypertension. The function of ENaC in Na+ reabsorption depends critically on its ability to discriminate between Na+ and other ions like K+ or Ca2+. ENaC is virtually impermeant to K+ ions, and the molecular basis for its high ionic selectivity is largely unknown. We have identified a conserved Ser residue in the second transmembrane domain of the ENaC alpha subunit (alphaS589), which when mutated allows larger ions such as K+, Rb+, Cs+, and divalent cations to pass through the channel. The relative ion permeability of each of the alphaS589 mutants is related inversely to the ionic radius of the permeant ion, indicating that alphaS589 mutations increase the molecular cutoff of the channel by modifying the pore geometry at the selectivity filter. Proper geometry of the pore is required to tightly accommodate Na+ and Li+ ions and to exclude larger cations. We provide evidence that ENaC discriminates between cations mainly on the basis of their size and the energy of dehydration.  (+info)

Effect of cations on purine.purine.pyrimidine triple helix formation in mixed-valence salt solutions. (6/762)

The effect of various monovalent, divalent and oligovalent cations on the reaction of triplex formation by GT and AG motif triplex-forming oligonucleotides, designed to bind to biologically relevant polypurine-polypyrimidine sequences occurring in the promoters of the murine Ki-ras and human bcr genes, has been investigated by means of electrophoresis mobility shift assays (EMSA) and DNase I footprinting experiments. We found that in the presence of 10 mm MgCl2 the triple helices were progressively destabilized by adding increasing amounts of NaCl, from 20 to 140 mm, to the solution. We also observed that, while the total monovalent-ion concentration was constant at 100 mm, the exchange of sodium with potassium, but not lithium, results in a further destabilization of the triple helices, due to self-association equilibria involving the G-rich triplex-forming oligonucleotides. Potassium was found to destabilize triplex DNA even when the triple helices are preformed in the absence of K+. However, footprinting experiments also showed that the inhibitory effect of K+ on triplex DNA is partially compensated for by millimolar amounts of divalent transition metal ions such as Mn2+ and Ni2+, which upon coordinating to N7 of guanine are expected to enhance hydrogen-bond formation between the target and the third strand, and to reduce the assembly in quadruple structures of G-rich triplex-forming oligonucleotides. Triplex enhancement in the presence of potassium was also observed, but to a lesser extent, when spermine was added to the reaction mixture. Here, the ion effect on triplex DNA is rationalized in terms of competition among the different valence cations to bind to triplex DNA, and differential cation stabilization of unusual quadruplex structures formed by the triplex-forming oligonucleotides.  (+info)

Analysis of calcium-induced calcium release in cardiac sarcoplasmic reticulum vesicles using models derived from single-channel data. (7/762)

The planar lipid bilayer and vesicle release experiments are two alternative approaches used to study the function of the ryanodine receptor (RyR) channel at the subcellular level. In this work, we combine models of gating (Zahradnikova and Zahradnik, Biophys. J. 71 (1996) 2996-3012) and permeation (Tinker et al., J. Gen. Physiol. 100 (1992) 495-517) of the cardiac RyR channel to simulate calcium release experiments on sarcoplasmic reticulum vesicles. The resulting model and real experimental data agreed well within the experimental scatter, confirming indistinguishable properties of the RyRC in the vesicle preparation and in the planar lipid bilayer. The previously observed differences in calcium dependencies of the release and the gating processes can be explained by binding of calcium within the RyRC conducting pore. A novel method of analysis of calcium dependence of calcium release was developed and tested. Three gating models of the RyRC, showing, respectively, an increase, no change, and a decrease in calcium sensitivity over time, were compared. The described method of analysis enabled determination of temporal changes in calcium sensitivity, giving potential for detection of the adaptation/inactivation phenomena of the RyRC in both vesicle and in situ release experiments.  (+info)

Functional characterization of the Betaine/gamma-aminobutyric acid transporter BGT-1 expressed in Xenopus oocytes. (8/762)

Betaine is an osmolyte accumulated in cells during osmotic cell shrinkage. The canine transporter mediating cellular accumulation of the osmolyte betaine and the neurotransmitter gamma-aminobutyric acid (BGT-1) was expressed in Xenopus oocytes and analyzed by two-electrode voltage clamp and tracer flux studies. Exposure of oocytes expressing BGT-1 to betaine or gamma-aminobutyric acid (GABA) depolarized the cell membrane in the current clamp mode and induced an inward current under voltage clamp conditions. At 1 mM substrate the induced currents decreased in the following order: betaine = GABA > diaminobutyric acid = beta-alanine > proline = quinidine > dimethylglycine > glycine > sarcosine. Both the Vmax and Km of GABA- and betaine-induced currents were voltage-dependent, and GABA- and betaine-induced currents and radioactive tracer uptake were strictly Na+-dependent but only partially dependent on the presence of Cl-. The apparent affinity of GABA decreased with decreasing Na+ concentrations. The Km of Na+ also depended on the GABA and Cl- concentration. A decrease of the Cl- concentration reduced the apparent affinity for Na+ and GABA, and a decrease of the Na+ concentration reduced the apparent affinity for Cl- and GABA. A comparison of 22Na+-, 36Cl--, and 14C-labeled GABA and 14C-labeled betaine fluxes and GABA- and betaine-induced currents yielded a coupling ratio of Na+/Cl-/organic substrate of 3:1:1 or 3:2:1. Based on the data, a transport model of ordered binding is proposed in which GABA binds first, Na+ second, and Cl- third. In conclusion, BGT-1 displays significant functional differences from the other members of the GABA transporter family.  (+info)

Two mechanisms of passive Ca2+ transport, Na+-Ca2+ exchange and Ca2+-Ca2+ exchange, were studied using highly-purified dog heart sarcolemmal vesicles. About 80% of the Ca2+ accumulated by Na+-Ca2+ exchange or Ca2+-Ca2+ exchange could be released as free Ca2+, while up to 20% was probably bound. Na+-Ca2+ exchange was simultaneous, coupled countertransport of Na+ and Ca2+. The movement of anions during Na+-Ca2+ exchange did not limit the initial rate of Na+-Ca2+ exchange. Na+-Ca2+ exchange was electrogenic, with a reversal potential of about -105 mV. The apparent flux ratio of Na+-Ca2+ exchange was 4 Na+:1 Ca2+. Coupled cation countertransport by the Na+-Ca2+ exchange mechanism required a monovalent cation gradient with the following sequence of ion activation: Na+ much greater than Li+ greater than Cs+ greater than K+ greater than Rb+. In contrast to Na+-Ca2+ exchange, Ca2+-Ca2+ exchange did not require a monovalent cation gradient, but required the presence of Ca2+ plus a monovalent cation on both sides
Date Published: March 22, 2018 Publisher: Springer Berlin Heidelberg Author(s): Paolo Bollella, Yuya Hibino, Kenji Kano, Lo Gorton, Riccarda Antiochia. http://doi.org/10.1007/s00216-018-0991-0 Abstract We report on the influence of pH and monovalent/divalent cations on the catalytic current response, internal electron transfer (IET), and structure of fructose dehydrogenase (FDH) by using amperometry, spectrophotometry, and circular dichroism (CD).…
Gramicidins bactericidal activity is a result of increasing the permeability of the bacterial cell wall allowing inorganic monovalent cations (e.g. H+) to travel through unrestricted, thereby destroying the ion gradient between the cytoplasm and the extracellular environment. That gramicidin D functions as a channel was demonstrated by Hladky and Haydon, who investigated the unit conductance channel. In general, gramicidin channels are ideally selective for monovalent cations and the single-channel conductances for the alkali cations are ranked in the same order as the aqueous mobilities of these ions. Divalent cations like Ca-2+ block the channel by binding near the mouth of the channel. So it is basically impermeable to divalent cations. It also excludes anions. Cl- in particular is excluded from the channel because its hydration shell is thermodynamically stronger than that of most monovalent cations. The channel is permeable to most monovalent cations, which move through the channel in ...
In aqueous solutions, an elongated, negatively charged DNA chain can quickly change its conformation into a compacted globule in the presence of positively charged molecules, or cations. This well-known process, called DNA compaction, is a highly potential method for gene therapy and delivery. Experimental c
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We showed that both Ca2+ and Mg2+ exhibit anomalous mole-fraction effects at normal physiological pH. The apparent affinity of TRPM7 is 47.1 μM for Ca2+ and 5.4 μM for Mg2+, similar to the previously reported Ca2+ (20 μM, at −120 mV) (Fomina et al., 2000) and Mg2+ affinity (3 μM, at −120 mV) to native MIC/MagNuM channels (Kerschbaum et al., 2003). Under normal physiological Ca2+ (2 mM) and Mg2+ (0.7-1.1 mM) concentrations (Konrad et al., 2004), we showed that monovalent cations contribute to the inward currents of TRPM7 (Fig. 3), and the contribution of monovalent currents becomes more pronounced under acidic conditions (pH 4.0, Fig. 4).. Several lines of evidence shown in the present study indicate that external protons increase TRPM7 inward currents by competing with divalent cations for binding sites in the TRPM7 pore, thereby enhancing monovalent cation permeability. First, there was a concentration-dependent increase in monovalent cation conductance and reversal potential for Na+, ...
mode, was anticipated by work with more intensively These additional catalytic modes, which will be detailed studied Tet proteins and was confirmed by Yamaguchi et further below, have in common the use of cationic al. (1995) and Guffanti and Krulwich (1995). Modes II and substrates with single net charge, but the cytoplasmic III, the Monovalent cation/H+ Antiport and Monovalent substrates range from a Tc- -Me2+ complex that has regions cation or Tc- -Me2+/K+ Antiport (the Net K+ Uptake Mode), with highly non-polar features to highly hydrated respectively, were unanticipated, although Ives and Bott monovalent cations. The substrate diversity of Tet(L) and (1990) speculated that tetL was likely to have a Tc-unrelated Tet(K) opens up some of the same questions that are function of physiological significance. Chromosomally central to function of those MDRs whose substrates encoded Tet(L) from Bacillus subtilis was identified as a encompass diverse structures and both non-polar and polar possible ...
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Among the most critical factors for geological CO2 storage site screening, selection and operation is effective simulation of multiphase flow and transport. Relative permeability is probably the greatest source of potential uncertainty in multiphase flow simulation, second only to intrinsic permeability heterogeneity. The specific relative permeability relationship assigned greatly impacts forecasts of CO2 trapping mechanisms, phase behavior, and long-term plume movement. A primary goal of this study is to evaluate the impacts and implications on CO2-EOR model forecasts of different methods of assigning relative permeability relationships.. We applied a novel approach to assigning relative permeability relationships in numerical models. In previous research, most models assign relative permeability functions on the basis of geologic formation or rock type. In this study, we assign and calibrate relative permeability by hydrostratigraphic units, extending the seminal work of Maxey (1964) to ...
TY - GEN. T1 - Assessment of three phase relative permeability and hysteresis models for simulation of water-alternating-gas (WAG) injection in water-wet and mixed-wet systems. AU - Shahrokhi, Omid. AU - Fatemi, Seyyed Mobeen. AU - Sohrabi, Mehran. AU - Ireland, Shaun. AU - Ahmed, Kamran. PY - 2014/1/1. Y1 - 2014/1/1. N2 - Obtaining reliable relative permeability (kr) values and their variations is difficult particularly in processes involving three-phase flow and flow reversal (e.g. WAG injection) which results in kr hysteresis. The current approach in the industry is to use a three-phase kr correlation (e.g., Stone I, Stone II, Baker) in conjunction with a kr hysteresis model (e.g., Killough, WAG- Hysteresis). However, these models have been mostly developed based on water-wet systems and have rarely been benchmarked against experimental measurements. In this paper, we present the results of an extensive assessment of different three-phase relative permeability models available in the most ...
A further investigation of a chromatographic system allowing determination of hydrogen ions is reported. For this purpose an octadecylsilica column dynamically modified with sodium dodecylsulfate (SDS) or lithium dodecylsulfate (LDS) was used as stationary phase and a slightly acidified electrolyte (usually KCl)-SDS solution was used as the eluent. The concentration of SDS, KCl and the acidity of the eluent affected the structure of aggregates formed by the molecules of dodecylsulfate at the surface of the stationary phase. These aggregates of dodecylsulfate were found to be responsible for the appearance of a chromatographic peak attributed to the presence of H3O+ ions in a sample. Other cations in the sample could be separated in the same manner, permitting the simultaneous separation of monovalent cations from H3O+. The detection limit for H3O+ ions was 2.25·10−6 M using an eluent comprising 0.3 mM LDS, 50.0 mM KCl and 0.10 mM H2SO4. The proposed method is shown to be applicable for the ...
The directed movement of inorganic cations with a valency of one into, out of, within or between cells. Inorganic cations are atoms or small molecules with a positive charge which do not contain carbon in covalent linkage ...
The directed movement of inorganic cations with a valency of one into, out of, within or between cells. Inorganic cations are atoms or small molecules with a positive charge which do not contain carbon in covalent linkage ...
View Notes - 0243Pb45anp2-09 from CHEM orgo at NYU. + + Both cations (these are NOT resonance forms - they are two separate cations) are captured - two steps please - to give the two final products.
A method of treating a subterranean formation including providing a well bore that includes a filter cake on at least a portion of the well bore and contacting at least a portion of the filter cake with a filter cake degradation fluid comprising a relative permeability modifier. The method also includes allowing the relative permeability modifier to retain at least a portion of the filter cake degradation fluid in the well bore for a time sufficient to contact the filtercake and allowing the filter cake to degrade.
Article: Teamwork allows people to discuss their work together, and as a result, to grow professionally. To be successful, the teacher and para-educator must view themselves as a team and partners in the educational process ...
1776. Somme des cations échangeables (S) : Somme des cations métalliques échangeables exprimée en milliéquivalents-grammes pour 100 grammes de complexe absorbant ...
The next part of the work moved towards describing the modelling methods attempted for modifying the relative permeability which is the main focus of the research and the success achieved through applying the unique flexible restart with Relative Permeability to Water (KRW) reduction method. This method was used with multiple reduction sensitivities on both a single well and at full field scale. The relative permeability to water was reduced by 10, 20, 30, 40 and 50% in the single well modification case. An additional sensitivity of 60% reduction was also modelled on the full field case. The change to KRW was applied in the perforation zones of each well. Overall, the oil ultimate recovery (EUR) is improved in all the wells and across all the reduction scenarios. There was an immediate change in terms of the oil rate increasing and water rate and water cut decreasing. The oil rates were increased by 2% to 51% in the first 3 months post treatment for the 10% to 60% modifications respectively. The ...
Fig. 5. Proton-activated currents associated with AtMHX expression in vacuolar giant patches. (A) Patch from a vacuole of a transformed cell. Currents are activated by switching from a pH 7.7 solution to a pH 5.7 solution and back to pH 7.7. N-methyl-glucamine (NMG) is the only monovalent cation in solution. The pipette solution (pH 7.0; cytoplasmic membrane side) contains 2 mM Mg2 and 2 mM Ca2 ; the bath solution contains 0.5 mM Mg2 . (B) Typical current records for the same protocol in a vacuolar patch from a non-transformed cell. (C) Current-voltage relations for the proton-activated current in Figure 5A (2-1), whereby records were subtracted just before (1) and after (2) application of the pH 5.7 solution. In addition, the current- voltage relation is given for the reverse current observed on removing protons, whereby the subtracted records were obtained just after returning to pH 7.7 (3) and 30 s later when the current had decayed (4). (D) Current-voltage relation of the 10 times smaller current
He catalytic activity; replacement of HEPES/KOH buffer with TRIS/HCl abolished the enzymatic activity unless a monovalent cation was present (Figure 3C). Among
Three phase Relative Permeability is one of the topic in which we provide homework and assignment help. Assignmenthelp.net provides email based assignment help, honmework help, online tutoring in all subjects.
Synonyms for Cations, divalent in Free Thesaurus. Antonyms for Cations, divalent. 1 synonym for divalent: bivalent. What are synonyms for Cations, divalent?
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View Notes - unk9scheme[1](2) from CHM 2045L at University of Florida. Instruction for unknown 9A/9B The author is not responsible for the scheme! Possible ions: 1. Cations: Na+, K+, NH4+, Ca2+,
Maximum efficiency of cation hydrolysis will be shown by? a) \(\sf Al^{+3}\) b) \(\sf Tl^{+3}\) c) \(\sf Tl^{+1}\) d) \(\sf Ga^{+3}\)The answer i...
TY - JOUR. T1 - Regulation of connexin hemichannels by monovalent cations. AU - Srinivas, Miduturu. AU - Calderon, D. Paola. AU - Kronengold, Jack. AU - Verselis, Vytautas. PY - 2006/1. Y1 - 2006/1. N2 - Opening of connexin hemichannels in the plasma membrane is highly regulated. Generally, depolarization and reduced extracellular Ca2+ promote hemichannel opening. Here we show that hemichannels formed of Cx50, a principal lens connexin, exhibit a novel form of regulation characterized by extraordinary sensitivity to extracellular monovalent cations. Replacement of extracellular Na+ with K+, while maintaining extracellular Ca2+ constant, resulted in ,10-fold potentiation of Cx50 hemichannel currents, which reversed upon returning to Na+. External Cs+, Rb+, NH4+, but not Li +, choline, or TEA, exhibited a similar effect. The magnitude of potentiation of Cx50 hemichannel currents depended on the concentration of extracellular Ca2+, progressively decreasing as external Ca 2+ was reduced. The primary ...
Relative permeability is one of the key parameters governing fluid flow through porous media. Determination of relative permeability is traditionally conducted in the laboratory using either recombined reservoir oil or laboratory oil at simulated reservoir conditions, or simply at laboratory conditions. This is because it is expensive to sample representative uncontaminated reservoir fluids and extremely difficult to cut reservoir cores without altering their surface properties. Restoring rock properties to their original reservoir conditions has been a technical challenge to the industry. Upscaling laboratory special core-analysis data to reservoir scale is also a concern. Consequently, the industry has been researching new methods to extract relative permeability in situ, including the utilization of specially designed permanent downhole electric resistivity array, pressure and flow rate measurements. In this study, a different approach was taken. A semi-analytical model, developed to infer ...
Summary The complex physics of multiphase flow in porous media are usually modeled at the field scale using Darcy-type formulations. The key descriptors of such models are the relative permeabilities to each of the flowing phases. It is well known t
Wolf, R., Dommröse, A. - M., & Grützmacher, H. - F. (1988). Destabilized carbenium ions: secondary and tertiary [alpha]-carbomethoxybenzyl cations. Organic Mass Spectrometry, 23(1), 26-32. doi:10.1002/oms. ...
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TRPV6 / ECAC2, 0.1 ml. FUNCTION: Calcium selective cation channel probably involved in Ca(2+) uptake in various tissues, including Ca(2+) reabsorption in intestine.
வேதியியலில் உப்பு (salt) என்பது ஒரு காடியும், காரமும் சேர்ந்து வேதியியல் வினைப்படும் பொழுது நடுமை அடைகையில் உருவாகும் பொருள். உப்புகள் மின்ம முனைப்படும் சேர்மங்கள் ஆகும். உப்புகளில் நேர்மின்மம் கொண்ட நேர்முனையி அல்லது கேட்டயான் (cation) பகுதியும், எதிர்மின்மம் கொண்ட எதிர்முனையி அல்லது ஆனையான் (anion) பகுதியும் கொண்ட ஆனால் மொத்தமாக மின்மம் ஏதுமற்ற, மின்மநடுநிலை கொண்ட ஒரு பொருள். ...
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Prokaryotic and eukaryotic proteins cluster separately but probably function with the same polarity by similar mechanisms. These proteins are secondary carriers which utilize the pmf and function by H antiport (for metal efflux). One member, CzcD of Bacillus subtilis, has been shown to exchange the divalent cation (Zn2+ or Cd2+ ) for two monovalent cations (K+ and H+ ) in an electroneutral process energized by the transmembrane pH gradient (Guffanti et al., 2002). Another, ZitB of E. coli (TC #2.A.4.1.4), has been reconstituted in proteoliposomes and studied kinetically (Chao and Fu, 2004a). It appears to function by simple Me2+:H antiport with a 1:1 stoichiometry.. Montanini et al (2007) have conducted phylogenetic analysis of CDF family members. Their analysis revealed three major and two minor phylogenetic groups. They suggest that the three major groups segregated according to metal ion specificity: (1) Mn2+ , (2) Fe2+ and Zn2+ as well as other metal ions, and (3) Zn2+ plus other metals, but ...
1. Balance the following equation. What is the sum of the coefficients of the reactants and products? C7H16 + ____ O2 - , ____ CO2 + ____ H2O a) 21 b) 24 c) 18 d) 27 2. An atom has an atomic number of 7 and a mass number of 14. How many electrons will it have in its valence level: a) 2 b) 3 c) 4 d) 5 3. Calculate the molar concentration of the solution produced by dissolving 11g of K2SO4 in 125 cm3 of water (atomic masses are: K=39; S=32; O=16) a) 0.05 M b) 0.5 M c) 0.25 M d) 0.025 M 4. Select a group of acids according to Brönsted concept: a) CH3COO-, HCl, H2O, HCO3- b) HCl, H2O, NH4+, HS- c) H2SO4, Cl-, H3O+, CH3NH2 d) H2CO3, CH3NH2, H3O+, HCl 5. The bond between sulfur and chlorine would be: a) not formed b) ionic c) polar covalent d) nonpolar covalent 6. How many protons, neutrons, and electrons does monovalent cation of 31H have? a) 1, 2, 0 b) 2, 1, 3 c) 3, 2, 1 d) 1, 2, 3 7. As you move up and to the right on the periodic table: a) atomic radius increases and electronegativity increases ...
Read interesting answers and in fact write your own answer to the question which element ionic radius is smaller than its atomic radius?
In the present study we report the synthesis, crystal structure and Raman spectroscopy studies of Na1-xKxPb4(VO4)(3) orthovanaclates solid solutions (0 ,= x ,= 1). Rielveld refinements showed that this solid solution is continuous adopting P6(3)/m (no. 176) space group. Some of Pb(II) cations are located in the (6 h) sites. The ninefold coordination sites (4f) are equally occupied by the other lead cations and the K+ and Na+ monovalent ions. The structure can be described as built up from [VO4](3-) tetrahedral and Ph2+ of sixfold coordination cavities (6 h positions), which delimit void hexagonal tunnels running along [0 0 1]. These tunnels are connected by cations of mixed sites (4f) half occupied by Pb(II) and half by Na+/K+ mixed cations. The existence of this type of lacunar apatite seems to be conditioned by the presence of lone pair cations Pb(II). Raman spectra of all the compositions are similar and show some linear shifts in band positions as a function of the composition toward high ...
KrwHonarpourCarbInterWet - Honarpour correlation for predicting water relative permeability in intermediately wet limestone and dolomite.
Determination of cations in beverages - Food and Beverage - Beverage by Lumex Instruments Group. The method enables fast determination of inorganic cations ...
Polarizability is the inclination of electrons to be distorted in an anion. Polarizing power is the ability of a cation to distort electrons of an anion. The size of cations are pretty small in comparison to the size of anions, since the radii of cations are small, their nucleus has enough pulling energy to pull onto (or distort) the electrons of an anion, and an anions size is bigger and their electrons are farther from the nucleus and the nucleus cannot hold onto the electrons that are further away from it. I think of it as, polarizability = anions, polarizing power = cations ...
Every ionic bond will result in the formation of an anion and a cation. The anion is the atom which receives the electron (usually the nonmetal with a large EN) and the cation is the atom which donates the electron (usually the metal with a low EN). Because of this, we can say that as EN increases going right across the periodic table, so does the likelihood of the element forming an anion when in an ionic bond. Vice versa, we can say that as EN decreases going left across the periodic table, so does the likelihood of an element forming a cation when in an ionic bond ...
تبذل الصناعة النفطية جهودا كبيرة لتحسين انتاج النفط في ظل عدم استقرار أسعاره. حقن الماء الذكي يوفر فرصة للحصول على كمية إضافية من النفط بعمليات قليلة التكلفة. يمكن الحصول على نسب إضافية من النفط تتراوح بين الصفر إلى 30 % عن طريق تعديل الملوحة أو تغيير مدى محدد من الأيونات عند حقن الماء المالح في التجارب المعملية. هذه التغييرات في النسبة الإضافية المتحصل عليها مرتبطة بنقص فهم آليات عمل حقن الماء الذكي مما يؤثر على تفسير النتائج المعملية و نتائج نماذج المحاكاة. تهدف هذه الدراسة للنظر عن قرب لهذه الظاهرة المتناقضة عن طريق تأكيد فوائد تطبيق الحقن المتتابع ...
Using Periodic Properties to Identify Group 2A Cations and Group 7A Anions Objectives The objectives of this lab are as follows: To observe the solubility properties of various ionic compounds containing
Calixarene-Based Molecules for Cation Recognition. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
Müller, A., Krickemeyer, E., Bögge, H., Schmidtmann, M., Botar, B., & Talismanova, M. O. (2003). Drawing small cations into highly charged porous nanocontainers reveals Water assembly and related interaction problems. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 42(18), 2085-2090. doi:10.1002/anie. ...
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ADP can be replaced by GDP, ATP and GTP, to a limited extent. Divalent cations are necessary for activity, with Mg2+ followed by Co2+ being the most effective ...
Philippaert K, Kerselaers S, Voets T, Vennekens R (April 2018). "2+-Activated Monovalent Cation-Selective Channels". SLAS ... Ketoconazole has been found to inhibit the activity of the cation channel TRPM5. When administered orally, ketoconazole is best ...
The most important cations for the action potential are sodium (Na+) and potassium (K+). Both of these are monovalent cations ... ISBN 978-0-12-664661-0. Hodgkin AL, Keynes RD (1955). "Active transport of cations in giant axons from Sepia and Loligo". J. ... Action potentials can also involve calcium (Ca2+), which is a divalent cation that carries a double positive charge. The ... Being an anion, the chloride terms are treated differently from the cation terms; the intracellular concentration is in the ...
... A is an ionophore related to the crown ethers with a preference to form complexes with monovalent cations such as: Li+ ... Pinkerton, M.; Steinrauf, L. K. (1970). "Molecular structure of monovalent metal cation complexes of monensin". J. Mol. Biol. ... Monensin A is able to transport these cations across lipid membranes of cells in an electroneutral (i.e. non-depolarizing) ... The antibacterial properties of monensin and its derivatives are a result of their ability to transport metal cations through ...
Divalent cations may also substitute for the monovalent cation K+ in the A site. Charge balance may be achieved in three ways. ... Firstly by replacing two monovalent cations by one divalent cation, and leaving an A site vacancy, as in plumbogummite, Pb2+Al3 ...
"The missing crystal structures of fluorosulfates of monovalent cations: M(I)SO3F, M=Na, Rb and Tl". Journal of Fluorine ... The fluorosulfate ion has a low propensity to form complexes with the metal cation. Since fluorine is similar in size to oxygen ...
The reverse holds for cation-exchange membranes. The so-called heterogeneous ion-exchange membranes have low cost and a thicker ... Homogeneous membrane surfaces can be modified to alter the membrane permselectivity to protons, monovalent ions, and divalent ... Important examples of ion-exchange membranes include the proton-exchange membranes, that transport H+ cations, and the anion ... When applied in an electrodialysis desalination process, anion- and cation-exchange membranes are typically arranged in an ...
Gold cations can be dispersed atomically on basic metal oxide supports such as MgO and La2O3. Monovalent and trivalent gold ... leaving behind highly active cations. According to DFT calculations, the presence of such Au cations on the catalyst is allowed ... thin films and nanoparticles are one to two orders of magnitude more active than atomically dispersed gold cations or ... cations have been identified, the latter being more active but less stable than the former. The turnover frequency (TOF) of CO ...
Essentially these arise when the cation:uranium ratio is different from 2:1 (monovalent cations) or 1:1 (divalent cations). ... For example, with the cation K+, compounds with K:U ratios of 2, 1 and 0.5 were found, corresponding to empirical formulas ... where M represents a cation. The uranium atom in uranates(VI) has two short collinear U-O bonds and either four or six more ... Charge-balance constrains the number of oxygen atoms to be equal to half the sum of charges of the cations and uranyl groups. ...
... journals on the polarographic analysis of hydroxamic acids and electrolytic reduction of monovalent and polyvalent cations. She ...
... a monovalent cation-specific channel involved in calcium release from intracellular stores. It is extremely likely that there ...
... is able to make neutral complexes with monovalent and divalent cations and transport them through apolar phase ( ... including lipid bilayer membranes). It can also transport big organic cations like dopamine. Horses and dogs are very ...
... bind more strongly than monovalent cations (Na+). Inorganic materials called zeolites also exhibit ion-exchange properties. ... Water softening is the removal of calcium, magnesium, and certain other metal cations in hard water. The resulting soft water ... Ion-exchange resins are organic polymers containing anionic functional groups to which the divalent cations (Ca2+) ...
As of April 2016, the CPA superfamily consists of four members: 2.A.37 - The Monovalent Cation:Proton Antiporter-2 (CPA2) ... the monovalent cation:proton antiporter-2 (CPA2; TC# 2.A.37). CPA1 was considered a member of the superfamily until 2010, when ... The Cation:Proton Antiporter (CPA) Superfamily is a superfamily of transport proteins named after one of its constituent ...
Unlike its heavier congeners, it is not known to form a simple B3+ or hydrated [B(H2O)4]3+ cation. The small size of the boron ... Such compounds include astatides (XAt), astatates (XAtO3), and monovalent interhalogen compounds. Restrepo et al. reported that ... It is not known to form a cation. Silicon can form alloys with metals such as iron and copper. It shows fewer tendencies to ... Whether or not germanium forms a cation is unclear, aside from the reported existence of the Ge2+ ion in a few esoteric ...
PIH has now been demonstrated in natrolites containing Li, K, Rb and Ag as monovalent cations as well as in large-pore zeolites ...
... cation symporter (proton glutamate symporter) Monovalent cation/proton antiporter (Sodium/proton antiporter 1 NhaA) ... Nicholson, L. K.; Cross, T. A. (1989). "Gramicidin cation channel: an experimental determination of the right-handed helix ...
Related precipitations occur for sources of soft trivalent cations (As3+, Sb3+, Bi3+) and monovalent cations (Ag+, Cu+). ... Thus, treatment of aqueous solutions of many metal cations to a solution of thioacetamide affords the corresponding metal ...
The GHK voltage equation for M {\displaystyle M} monovalent positive ionic species and A {\displaystyle A} negative: E m = R T ... cations\ C} }P_{\mathrm {C} }\left[\mathrm {C} ^{+}\right]_{\mathrm {out} }+\sum _{\mathrm {anions\ A} }P_{\mathrm {A} }\left[\ ... If all the ions are monovalent-that is, if all the nA equal either +1 or -1-this equation can be written w − v e μ = 0 {\ ... cations\ C} }P_{\mathrm {C} }\left[\mathrm {C} ^{+}\right]_{\mathrm {in} }+\sum _{\mathrm {anions\ A} }P_{\mathrm {A} }\left[\ ...
... and monovalent cations, typically potassium (K) ions The reaction is commonly carried out in a volume of 10-200 μL in small ... bivalent cations, typically magnesium (Mg) or manganese (Mn) ions; Mg2+ is the most common, but Mn2+ can be used for PCR- ...
It transports monovalent cations with the selectivity: K ≈ Rb ≈ Cs ≫ Li ≈ Na ≈ NMGM (protonated N-methyl-D-glucamine). Activity ...
The β subunit has a fold type II conformation and a binding site adjacent to the active site for monovalent cations.[10] Their ...
... cation is a univalent or monovalent cation, whereas the Ca2+ cation is a divalent cation, and the Fe3+ cation is a trivalent ... Species with a single charge are univalent (monovalent). For example, the Cs+ ... cation. Unlike Cs and Ca, Fe can also exist in other charge states, notably 2+ and 4+, and is thus known as a multivalent ( ...
... and probably other divalent cations) can complex with Pi. The mammalian proteins (i.e., TC# 2.A.20.2.7) have been reported to ... 1Pi and with an apparent preference for the monovalent over the divalent form of Pi (see TC #2.A.20.2.5). The generalized ...
"RC-81.1.1. Monovalent radical centers in saturated acyclic and monocyclic hydrocarbons, and the mononuclear EH4 parent hydrides ... Examples are tropylium and triphenylmethyl cations and the cyclopentadienyl anion. Haloalkanes are a class of molecule that is ...
Both of these are monovalent cations that carry a single positive charge. Action potentials can also involve calcium (Ca2+),[5] ... Spangler SG (1972). "Expansion of the constant field equation to include both divalent and monovalent ions". Ala J Med Sci. 9 ( ... Electrical signals within biological organisms are, in general, driven by ions.[3] The most important cations for the action ... which is a divalent cation that carries a double positive charge. The chloride anion (Cl−) plays a major role in the action ...
... monovalent or intermediate positive states of astatine coprecipitate with the insoluble salts of metal cations such as silver(I ... 4; this is only stable in neutral or alkaline solutions.[71] Astatine is also thought to be capable of forming cations in salts ... cation, [At(C5H5N)2]+, forms ionic compounds with perchlorate[63] (a non-coordinating anion[66]) and with nitrate, [At(C5H5N)2] ... It also shows some metallic behavior, including being able to form a stable monatomic cation in aqueous solution (unlike the ...
2O, where X is a monovalent cation such as potassium or ammonium.[5] ...
If the cation is a very strong reducing agent, such as Yb2+, [Ni(CN)4]2− can be reduced to [Ni2(CN)6]4− where nickel atom is in ... of Monovalent Thallium. Crystallographic and Spectroscopic Characterization of the New Compounds Tl2Ni(CN)4 and Tl2Pd(CN)4". ...
Loss of a single proton results in the monovalent hydrogenoxalate anion HC. 2O−. 4. A salt with this anion is sometimes called ... In the body, oxalic acid combines with divalent metallic cations such as calcium (Ca2+) and iron(II) (Fe2+) to form crystals of ...
Usually in higher pH ranges in addition to low ionic strength of solutions and domination of monovalent metal cations the ...
Examples are tropylium and triphenylmethyl cations and the cyclopentadienyl anion. Groups containing halogenEdit. Haloalkanes ... "RC-81.1.1. Monovalent radical centers in saturated acyclic and monocyclic hydrocarbons, and the mononuclear EH4 parent hydrides ...
Landé[2] estimated ionic radii by considering crystals in which the anion and cation have a large difference in size, such as ... where monovalent chalcogen ions reside on C3 lattice sites. It was found that chalcogen ions have to be modeled by ellipsoidal ... When an atom loses an electron to form a cation, the other electrons are more attracted to the nucleus, and the radius of the ... they are sometimes treated as if they were hard spheres with radii such that the sum of ionic radii of the cation and anion ...
... are known where A is a monovalent cation such as sodium, potassium, rubidium, caesium, or thallium(I), or a compound cation ... The specific combinations of univalent cation, trivalent cation, and anion depends on the sizes of the ions. For example, ...
Methylene may gain an electron yielding a monovalent anion methanidyl (CH•−. 2), which can be obtained as the trimethylammonium ... Magnesium monohydride cation. *Methylidyne radical. *Nitric oxide. *Nitrogen (molecular). *Nitrogen monohydride. *Nitrogen ...
The [Rg(H2O)2]+ cation is expected to be the softest among the metal cations. Due to relativistic stabilisation of the 7s ... Bashilova NI & Khomutova, TV 1984, 'Thallates of alkali metals and monovalent thallium formed in aqueous solutions of their ... note that astatide ions should form strong complexes with soft metal cations such as Hg2+, Pd2+, Ag+ and Tl3+; they list the ... involving the formation of Og2+ and Og4+ cations. Oganesson(II) oxide (OgO) and oganesson(IV) oxide (OgO2) are both expected to ...
Ca2+-Ca2+ exchange did not require a monovalent cation gradient, but required the presence of Ca2+ plus a monovalent cation on ... Coupled cation countertransport by the Na+-Ca2+ exchange mechanism required a monovalent cation gradient with the following ... Na+ inhibited Ca2+-Ca2+ exchange when Ca2+-Ca2+ exchange was supported by another monovalent cation. Both Na+-Ca2+ exchange and ... Ca2+-Ca2+ exchange did not require a monovalent cation gradient, but required the presence of Ca2+ plus a monovalent cation on ...
... doi.org/10.1007/s00216-018-0991-0 Abstract We report on the influence of pH and monovalent/divalent cations on the catalytic ... Contrary to CaCl2, addition of MgCl2 did not show any particular influence, whereas addition of monovalent cations (Na+ or K+) ... Addition of MgCl2 or of the monovalent cations shows, surprisingly, no effect on the electron transfer to the electron acceptor ... We report on the influence of pH and monovalent/divalent cations on the catalytic current response, internal electron transfer ...
... gramicidin channels are ideally selective for monovalent cations and the single-channel conductances for the alkali cations are ... The channel is permeable to most monovalent cations, which move through the channel in single file. The channel is filled with ... Its ability to bind and transport cations is due to the presence of cation-binding sites in the channel. Specifically, there ... Divalent cations like Ca-2+ block the channel by binding near the mouth of the channel. So it is basically impermeable to ...
Cation transport numbers for four of these electrolytes were measured in Franz cells by the electromo ... Results for skin showed the expected increase in cation permselectivity for monovalent cations and a 40-110-fold reduction in ... Human skin is permselective for the small, monovalent cations sodium and potassium but not for nickel and chromium.. ... Molar conductance and cation transport values at infinite dilution were extrapolated from these data and used to estimate ionic ...
This monovalent cation leak could be correlated to a nonselective cation conductance and to elevated activity of endogenous ... and G796R abolish anion exchange and induce a similar monovalent cation leak that is also similar to the cation leak observed ... a A mutated state only conducts monovalent cations and a B mutated state shows both transport activities, anion exchange and ... L. J. Bruce, H. C. Robinson, H. Guizouarn et al., "Monovalent cation leaks in human red cells caused by single amino-acid ...
... Abdi-Jalebi, Mojtaba Univ Cambridge, Dept Phys, Cavendish ... Such a shift infers that incorporation of these monovalent cations dedope the n-type perovskite films when formed without added ... Synchrotron X-ray diffraction reveals a pronounced shift in the main perovskite peaks for the monovalent cation-based films, ... This dedoping effect leads to cleaner bandgaps as reflected by the lower energetic disorder in the monovalent cation-doped ...
Cation binding and thermostability of FTHFS monovalent cation binding sites and thermostability of N10-formyltetrahydrofolate ... MONOVALENT CATION BINDING SITES IN N10-FORMYLTETRAHYDROFOLATE SYNTHETASE FROM MOORELLA THERMOACETICA. *DOI: 10.2210/pdb1fpm/pdb ... Green solid line show hydrophobic interactions and green dashed lines show π-π and π-cation interactions. ... Green solid line show hydrophobic interactions and green dashed lines show π-π and π-cation interactions. ...
... by using mixed-monovalent cations. By replacing some of the Cs+ with Rb+, a series of RbxCs1−xPbBr3 NCs were obtained. They ... by using mixed-monovalent cations. By replacing some of the Cs+ with Rb+, a series of RbxCs1−xPbBr3 NCs were obtained. They ... Tunable electrochemiluminescence properties of CsPbBr3 perovskite nanocrystals using mixed-monovalent cations L. Chen, Q. Kang ... Tunable electrochemiluminescence properties of CsPbBr3 perovskite nanocrystals using mixed-monovalent cations† ...
... are analyzed with respect to their virus retention capacity when using feed solutions based on monovalent and divalent salts ( ... Effect of divalent versus monovalent cations on the MS2 retention capacity of amino-functionalized ceramic filters ... Effect of divalent versus monovalent cations on the MS2 retention capacity of amino-functionalized ceramic filters J. Bartels, ... are analyzed with respect to their virus retention capacity when using feed solutions based on monovalent and divalent salts ( ...
One strategy is mediated by cation-proton antiporters (CPA). CPA1 genes found in bacteria, fungi, metazoa and plants have been ... cation/H+ exchanger) families are largely unknown. Phylogenetic analysis showed that three clades of the Na+-H+ exchanger (NHX ... One strategy is mediated by cation-proton antiporters (CPA). CPA1 genes found in bacteria, fungi, metazoa and plants have been ... functionally-characterized; though roles of plant CPA2 genes in KEA (K+-efflux antiporter) and CHX (cation/H+ exchanger) ...
Na+-K+-ATPase and Changes in ATP Hydrolysis, Monovalent Cation Affinity, and K+ Occlusion in Diabetic and Galactosemic Rats. ... Na+-K+-ATPase and Changes in ATP Hydrolysis, Monovalent Cation Affinity, and K+ Occlusion in Diabetic and Galactosemic Rats ... Na+-K+-ATPase and Changes in ATP Hydrolysis, Monovalent Cation Affinity, and K+ Occlusion in Diabetic and Galactosemic Rats ... Na+-K+-ATPase and Changes in ATP Hydrolysis, Monovalent Cation Affinity, and K+ Occlusion in Diabetic and Galactosemic Rats ...
... the magnitude of the acquired effective charge was on the order of 1 cation per 100 monomer units. For monovalent cations, the ... The binding of monovalent ions was demonstrated not to follow the Hofmeister order; multivalent cations except barium all ... Binding of monovalent and multivalent metal cations to polyethylene oxide in methanol probed by electrophoretic and diffusion ... Diffusion experiments directly show that the acetate anion with monovalent cations does not associate with PEO. Considering all ...
Effects of monovalent cations on folding kinetics of G-quadruplexes. Jing You, Hui Li, Xi-Ming Lu, Wei Li, Peng-Ye Wang, Shuo- ... Effects of monovalent cations on folding kinetics of G-quadruplexes. Jing You, Hui Li, Xi-Ming Lu, Wei Li, Peng-Ye Wang, Shuo- ... Effects of monovalent cations on folding kinetics of G-quadruplexes Message Subject (Your Name) has forwarded a page to you ... In the present study, we compared the effects of three monovalent cations (Li+, Na+, and K+) on G-quadruplex folding kinetics ...
In addition, the monovalent cations may, along with Mg2+ ions and surrounding residues of the protein, help orient the 1- ... Monovalent cations inhibit FBPase either by distorting the geometry of the active site or by retarding turnover or product ... It is postulated that monovalent cations activate FBPase by helping the Arg276 residue deshield the partial negative charge ... K+ and Li+ were used to study the kinetic effects of monovalent cations on porcine liver fructose-1,6-bisphosphatase (FBPase). ...
Philippaert K, Kerselaers S, Voets T, Vennekens R (April 2018). "2+-Activated Monovalent Cation-Selective Channels". SLAS ... Ketoconazole has been found to inhibit the activity of the cation channel TRPM5. When administered orally, ketoconazole is best ...
Monovalent" by people in this website by year, and whether "Cations, Monovalent" was a major or minor topic of these ... "Cations, Monovalent" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, MeSH (Medical ... Platelet shape change and cytoskeletal assembly: effects of pH and monovalent cation ionophores. Thromb Haemost. 1983 Jun 28; ... Below are the most recent publications written about "Cations, Monovalent" by people in Profiles. ...
The most important cations for the action potential are sodium (Na+) and potassium (K+). Both of these are monovalent cations ... ISBN 978-0-12-664661-0. Hodgkin AL, Keynes RD (1955). "Active transport of cations in giant axons from Sepia and Loligo". J. ... Action potentials can also involve calcium (Ca2+), which is a divalent cation that carries a double positive charge. The ... Being an anion, the chloride terms are treated differently from the cation terms; the intracellular concentration is in the ...
Monovalent cation transporters; establishing a link between bioinformatics and physiology Frans J. M. Maathuis. ...
This is a different story when working with real solutions containing several monovalent and multivalent ions. We have ...
Ion exchange equilibrium and structural changes in clinoptilolite irradiated with β- and γ-radiation : Monovalent cations. In: ... Ion exchange equilibrium and structural changes in clinoptilolite irradiated with β- and γ-radiation : Monovalent cations. / ... Ion exchange equilibrium and structural changes in clinoptilolite irradiated with β- and γ-radiation: Monovalent cations. ... with a concomitant decrease in cation-exchange capacity (CEC). Crystallographic parameters and especially exchangeable cation ...
The features of monovalent cation and divalent metal activation, as well as the inhibition by Zn2+ and Cd2+, are discussed in ... The features of monovalent cation and divalent metal activation, as well as the inhibition by Zn2+ and Cd2+, are discussed in ... The features of monovalent cation and divalent metal activation, as well as the inhibition by Zn2+ and Cd2+, are discussed in ... The features of monovalent cation and divalent metal activation, as well as the inhibition by Zn2+ and Cd2+, are discussed in ...
Srinivas, M., Calderon, D. P., Kronengold, J., & Verselis, V. (2006). Regulation of connexin hemichannels by monovalent cations ... Srinivas, M, Calderon, DP, Kronengold, J & Verselis, V 2006, Regulation of connexin hemichannels by monovalent cations, ... Regulation of connexin hemichannels by monovalent cations. In: Journal of General Physiology. 2006 ; Vol. 127, No. 1. pp. 67-75 ... Regulation of connexin hemichannels by monovalent cations. Miduturu Srinivas, D. Paola Calderon, Jack Kronengold, Vytautas ...
The Influence Of Monovalent Cations On The Stability Of Electrochemically Formed Nickel Fluoride �lms The Influence Of ... The stability of electrochemically formed NiF2 film in 1.0 M perchloric acid containing monovalent fluorides namely, NH4F, HF, ...
Resistance of active monovalent cation transport to pronase digestion of intact human erythrocytes. / Wagner, Henry; Smith, ... Resistance of active monovalent cation transport to pronase digestion of intact human erythrocytes. In: Archives of ... Wagner H, Smith TW, Young M. Resistance of active monovalent cation transport to pronase digestion of intact human erythrocytes ... Wagner, H., Smith, T. W., & Young, M. (1974). Resistance of active monovalent cation transport to pronase digestion of intact ...
New structures of the N-terminal 43 kDa fragment of the E. coli DNA gyrase B subunit reveal two discrete monovalent cation- ... The role of monovalent cations in the ATPase reaction of DNA gyrase. ...
Monovalent cation binding to cubic insulin crystals.,Gursky O, Li Y, Badger J, Caspar DL Biophys J. 1992 Mar;61(3):604-11. PMID ... Two localized monovalent cation binding sites have been identified in cubic insulin from 2.8 A-resolution difference electron ... Monovalent cation binding to cubic insulin crystals. Biophys J. 1992 Mar;61(3):604-11. PMID:1504238 ... Monovalent cations of ionic radius less than 1.5 A are required for crystal stability. Replacing Na+ with Cs+, Mg++, Ca++ or ...
Monovalent Cations and Transformation of Fibroblasts. VIII. Monovalent Cation Flux in Fibroblasts: Current Status. IX. The Cell ... Rapid Changes in Fibroblast Monovalent Cation Flux. IV. Later Changes in Monovalent Cations during Go/G1. V. Increased Na+, K+ ... V. Cation Transport and Electrical Membrane Properties. VI. Growth Stimulation and Cation Transport. VII. Concluding Remarks. ... Growth Cycle and Monovalent Cation Flux: Future Directions of Research. References. Index. ...
Tunable opto electrical properties of monovalent na divalent cd2 and trivalent bi3 cations doped cu2se thin films prepared by ...
Dicarboxylate/amino acid:cation symporter (proton glutamate symporter). *Monovalent cation/proton antiporter (Sodium/proton ...
Experimental determination of the diffusion of monovalent cation into wood:Effects of micro-cracks,wood structure,impregnation ...
  • We report on the influence of pH and monovalent/divalent cations on the catalytic current response, internal electron transfer (IET), and structure of fructose dehydrogenase (FDH) by using amperometry, spectrophotometry, and circular dichroism (CD). (chromoscience.com)
  • Amperometric measurements were performed on graphite electrodes, onto which FDH was adsorbed and the effect on the response current to fructose was investigated when varying the pH and the concentrations of divalent/monovalent cations in the contacting buffer. (chromoscience.com)
  • In contrast to Na+-Ca2+ exchange, Ca2+-Ca2+ exchange did not require a monovalent cation gradient, but required the presence of Ca2+ plus a monovalent cation on both sides of the vesicle membrane. (semanticscholar.org)
  • Addition of MgCl2 or of the monovalent cations shows, surprisingly, no effect on the electron transfer to the electron acceptor. (chromoscience.com)
  • We report significant improvements in the optoelectronic properties of lead halide perovskites with the addition of monovalent ions with ionic radii close to Pb 2+ . (diva-portal.org)
  • This is a different story when working with real solutions containing several monovalent and multivalent ions. (marvel-hydrogen.eu)
  • Cx46 hemichannels exhibited a modest increase upon substituting Na + with K + . Analyses of reciprocal chimeric hemichannels that swap NH 2 - and COOH-terminal halves of Cx46 and Cx50 demonstrate that the difference in regulation by monovalent ions in these connexins resides in the NH 2 -terminal half. (elsevier.com)
  • Analyses of reciprocal chimeric hemichannels that swap NH2- and COOH-terminal halves of Cx46 and Cx50 demonstrate that the difference in regulation by monovalent ions in these connexins resides in the NH2-terminal half. (elsevier.com)
  • Two localized monovalent cation binding sites have been identified in cubic insulin from 2.8 A-resolution difference electron density maps comparing crystals in which the Na+ ions have been replaced by Tl+. (proteopedia.org)
  • Nonmetals generally are more electronegative than metals, meaning that they have a stronger pull on their electrons - thus when they form ions, metals give up electrons (forming cations) and nonmetals take up electrons (forming anions). (answers.com)
  • are called ions - cations and anions. (answers.com)
  • Atoms of Metals lose electrons to empty their outer shell and become positive ions or cations.Atoms of non-metals gain electrons to fill their outer shell and become negative ions or anions. (answers.com)
  • Gaining or losing electrons atoms become ions (anions or cations). (answers.com)
  • Cations are most often metals, as cations are positively charged ions meaning they have lostelectron(s). (answers.com)
  • A simple cationic substitution can be represented in a compound of the general form A + X − in which cation B + replaces in part or in total cation A + . Both cations in this example have the same valence (+1), as in the substitution of K + (potassium ions) for Na + (sodium ions) in the NaCl (sodium chloride) structure. (britannica.com)
  • Both have a single valence electron in their outer shell, which they readily donate, creating positive ions, or Na + and K + cations. (asbmb.org)
  • K+ and Li+ were used to study the kinetic effects of monovalent cations on porcine liver fructose-1,6-bisphosphatase (FBPase). (semanticscholar.org)
  • de Carvalho, LPS & Blanchard, JS 2006, ' Kinetic analysis of the effects of monovalent cations and divalent metals on the activity of Mycobacterium tuberculosis α-isopropylmalate synthase ', Archives of Biochemistry and Biophysics , vol. 451, no. 2, pp. 141-148. (elsevier.com)
  • Contrary to CaCl2, addition of MgCl2 did not show any particular influence, whereas addition of monovalent cations (Na+ or K+) led to a slight linear increase in the maximum response current. (chromoscience.com)
  • though roles of plant CPA2 genes encoding K + -efflux antiporter (KEA) and cation/H + exchanger (CHX) families are largely unknown. (frontiersin.org)
  • In plants, CPA1 includes the well-studied Na + -H + exchanger (NHX) family, and the relatively obscure CPA2 family that includes K + efflux Antiporter (KEA) and Cation-H + exchanger (CHX) families. (frontiersin.org)
  • Calcium-activated non selective cation channel that mediates membrane depolarization. (tcdb.org)
  • Receptor-activated non-selective cation channel involved in detection of sensations such as coolness, by being activated by cold temperature below 25 degrees Celsius. (abcam.com)
  • Ca 2+ , a calcium cation) requires further substitutions to keep the structure electrically neutral. (britannica.com)
  • The experiments were performed either in PBS only or in presence of divalent cations of calcium and magnesium corresponding to their concentrations in the interstitial fluid. (ahajournals.org)
  • One strategy is mediated by monovalent cation-proton antiporters (CPA) that are classified in two superfamilies. (frontiersin.org)
  • These include elevated levels of transporters and enzymes that promote proton capture and retention (e.g., the ATP synthase and monovalent cation/proton antiporters), metabolic changes that lead to increased acid production, and changes in the cell surface layers that contribute to cytoplasmic proton retention. (nih.gov)
  • These studies show the centrality of monovalent cation/proton antiporters in this process while microbial genomics provides information about the constellation of such antiporters in individual strains. (nih.gov)
  • Detailed information about the properties of multiple antiporters in individual strains is starting to explain how specific monovalent cation/proton antiporters play dominant roles in alkaline pH homeostasis in cells that have several additional antiporters catalyzing ostensibly similar reactions. (nih.gov)
  • Consistent with predictions from polyelectrolyte models, we observed logarithmic dependences of proton affinity versus salt concentration of -0.96 0.03 and -0.52 0.01 with monovalent and divalent cations, respectively, and these results help clarify prior results that appeared to conflict with these fundamental models. (stanford.edu)
  • The addition of minute amounts of electrolytes to a suspensoid causes precipitation, while emulsoids are affected only slightly but will coalesce upon the addition of sufficient quantity of electrolyte, especially that containing the di- or trivalent cations. (nmfrc.org)
  • Since cations tend to lose electrons, their atomic radius will decrease in size, as the other electrons will be 'pulled in' more by the protons in the nucleus (meaning stronger bond). (answers.com)
  • After a general introduction, readers will find review articles covering the mechanisms and regulation of transport for various substrates ranging from diverse nutrients to cations, water and protons. (springer.com)
  • Several lines of evidence suggest that protons enhance TRPM7 inward currents by competing with Ca 2+ and Mg 2+ for binding sites, thereby releasing blockade of divalent cations on inward monovalent currents. (rupress.org)
  • Fourth, the anomalous-mole fraction behavior of H + permeation further suggests that protons compete with divalent cations for binding sites in the TRPM7 pore. (rupress.org)
  • Diffusion experiments directly show that the acetate anion with monovalent cations does not associate with PEO. (diva-portal.org)
  • The general chemical formula for pure perovskite compounds is ABX 3 (Fig. 1 a) where "A" and "B" are two cations of dissimilar size, and X is an anion that binds to both. (springer.com)
  • filter residue Gln973 is essential in defining monovalent selectivity. (tcdb.org)
  • Here, we show that single graphene nanopores preferentially permit the passage of K(+) cations over Cl(-) anions with selectivity ratios of over 100 and conduct monovalent cations up to 5 times more rapidly than divalent cations. (nih.gov)
  • The majority of the monovalent counterions are too mobile to show up in the electron density maps calculated using data only at resolution higher than 10 A. Monovalent cations of ionic radius less than 1.5 A are required for crystal stability. (proteopedia.org)
  • 4. A method as claimed in claim 1 in which the metal oxide forms a cation of large ionic radius. (google.co.uk)
  • Synchrotron X-ray diffraction reveals a pronounced shift in the main perovskite peaks for the monovalent cation-based films, suggesting incorporation of these cations into the perovskite lattice as well as a preferential crystal growth in Ag + containing perovskite structures. (diva-portal.org)
  • Such a shift infers that incorporation of these monovalent cations dedope the n-type perovskite films when formed without added cations. (diva-portal.org)
  • This dedoping effect leads to cleaner bandgaps as reflected by the lower energetic disorder in the monovalent cation-doped perovskite thin films as compared to pristine films. (diva-portal.org)
  • Our theoretical calculations confirm the observed shifts in X-ray diffraction peaks and Fermi level as well as absence of intrabandgap states upon energetically favorable doping of perovskite lattice by the monovalent cations. (diva-portal.org)
  • In summary, our work highlights the local chemistry and influence of monovalent cation dopants on crystallization and the electronic structure in the doped perovskite thin films. (diva-portal.org)
  • Herein, we demonstrate a simple approach for tuning the elecrochemiluminescence (ECL) properties of CsPbBr 3 perovskite nanocrystals (NCs) by using mixed-monovalent cations. (rsc.org)
  • The predicted seven-transmembrane α helices of ChR2 are characteristic for G protein-coupled receptors but reflect a different motif for a cation-selective ion channel. (pnas.org)
  • 4. Calixarene Based Cation Carriers and Receptors. (fishpond.co.nz)
  • Chemically Modified Calixarenes as New Selective Receptors for Monovalent Cations. (fishpond.co.nz)
  • Amperometric measurements were performed on graphite electrodes, onto which FDH was adsorbed and the effect on the response current to fructose was investigated when varying the pH and the concentrations of divalent/monovalent cations in the contacting buffer. (chromoscience.com)
  • whereas at high H + concentrations, the affinity of TRPM7 for Ca 2+ and Mg 2+ is decreased, thereby allowing monovalent cations to pass through TRPM7. (rupress.org)
  • Here we show that hemichannels formed of Cx50, a principal lens connexin, exhibit a novel form of regulation characterized by extraordinary sensitivity to extracellular monovalent cations. (elsevier.com)
  • Our results demonstrate a new, robust means of regulating hemichannels through a combination of extracellular monovalent and divalent cations, principally Na + , K + , and Ca 2+ . (elsevier.com)
  • Importantly, we show that the well-characterized endogenous TRPM7-like current MIC (Mg 2+ -inhibitable cation)/MagNuM (Mg nucleotide-regulated metal ion) in rat basophilic leukemia (RBL) cells is similarly potentiated by a decrease in extracellular pH. (rupress.org)
  • Strikingly, quantitation of the ion atmosphere content indicates that divalent cations are preferentially lost over monovalent cations upon A C protonation, providing experimental indication of the preferential localization of more highly charged cations to the inner shell of the ion atmosphere. (stanford.edu)
  • For example, the two end-members of olivine [(Mg, Fe) 2 SiO 4 ], forsterite (Mg 2 SiO 4 ) and fayalite (Fe 2 SiO 4 ), define a complete solid-solution series in which magnesium cations (Mg 2+ ) are replaced partially or totally by Fe 2+ . (britannica.com)
  • Targeted studies over the past decade have followed up the long-recognized importance of monovalent cations in active pH homeostasis. (nih.gov)
  • The effective charge of the tetramethylammonium cation ion in water, dimethylsulphoxide (DMSO), acetonitrile, methanol and ethanol was estimated by eNMR and diffusion measurements and compared to the value predicted by the Debye-Hückel-Onsager limiting law. (diva-portal.org)
  • In the present study, we investigated the folding kinetics of G-quadruplex in different monovalent cation environments and determined the detailed kinetic parameters for Na + - and K + -induced G-quadruplex folding, and for its structural transition from the basket-type Na + form to the hybrid-type K + form. (bioscirep.org)
  • Kinetics and mechanisms of activation and inhibition of porcine liver fructose-1,6-bisphosphatase by monovalent cations. (semanticscholar.org)
  • In this work we characterized the monovalent and divalent specificity of MtIPMS using steady-state kinetics. (elsevier.com)
  • We demonstrate by functional expression, both in oocytes of Xenopus laevis and mammalian cells, that ChR2 is a directly light-switched cation-selective ion channel. (pnas.org)
  • The exchanger itself mediates cation leak by a conductive mechanism [ 25 ]. (hindawi.com)
  • However, another explanation suggests that point-mutated AE1 could regulate a cation leak through other transporters. (hindawi.com)
  • Moreover, the transport features of some of these AE1 mutants lead to another interpretation, that is, cation leak is due to the activation of endogenous Na + and K + transporters (or channels) in red cell membrane by mutated AE1 [ 23 , 24 , 26 ]. (hindawi.com)
  • Monovalent cation transporters at the plasma membrane in yeasts. (nih.gov)
  • Cesium-saturated samples exhibited changes in the cation sites Cs2 and Cs3, which are next to clinoptilolite channel walls with lower Al 3+ for Si 4+ substitution. (elsevier.com)
  • In vertebrates, light-activated rhodopsin initiates a G protein-coupled enzyme cascade that ends in the hydrolysis of cGMP and the closure of the cGMP-regulated cation channels, thus hyperpolarizing the plasma membrane ( 1 - 3 ). (pnas.org)
  • The monovalent cation dependence of the kinetic parameters of substrates and divalent metals indicates that K + is the likely physiological activator. (elsevier.com)
  • It has been proposed that the molecular mechanism accounting for cation leaky red cells in these hereditary stomatocytoses was a change in AE1 transport properties induced by the point mutations. (hindawi.com)
  • The present study may shed new light on the roles of monovalent cations in G-quadruplex folding and should be useful for further studies of the underlying folding mechanism. (bioscirep.org)
  • Coupled cation countertransport by the Na+-Ca2+ exchange mechanism required a monovalent cation gradient with the following sequence of ion activation: Na+ much greater than Li+ greater than Cs+ greater than K+ greater than Rb+. (semanticscholar.org)
  • Among the flavocytochrome oxidoreductases, the DET mechanism for membrane bound FDH has not yet been elucidated [45] and therefore FDH has attracted a growing interest also regarding all factors that can influence the DET reaction (e.g., pH, cations, ionic strength, etc.) [46-48]. (chromoscience.com)
  • In the cell, RNA and DNA interact with cations that screen the negatively charged phosphate backbone. (pnas.org)
  • Cation transport numbers for four of these electrolytes were measured in Franz cells by the electromotive force method. (cdc.gov)
  • Molar conductance and cation transport values at infinite dilution were extrapolated from these data and used to estimate ionic conductances at infinite dilution. (cdc.gov)
  • These results indicate that the cation-transport complex is not readily accessible from the outer surface of native intact membranes. (elsevier.com)
  • Wagner, H , Smith, TW & Young, M 1974, ' Resistance of active monovalent cation transport to pronase digestion of intact human erythrocytes ', Archives of Biochemistry and Biophysics , vol. 163, no. 1, pp. 95-98. (elsevier.com)
  • Seems to act in monovalent cation transport (PubMed:18931342, PubMed:21849667). (genecards.org)
  • Ceramic capillary membranes conditioned for virus filtration via functionalization with n -(3-trimethoxysilylpropyl)diethylenetriamine (TPDA) are analyzed with respect to their virus retention capacity when using feed solutions based on monovalent and divalent salts (NaCl, MgCl 2 ). (rsc.org)
  • Cations, Monovalent" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (rush.edu)
  • Addition of MgCl2 or of the monovalent cations shows, surprisingly, no effect on the electron transfer to the electron acceptor. (chromoscience.com)
  • We report on the influence of pH and monovalent/divalent cations on the catalytic current response, internal electron transfer (IET), and structure of fructose dehydrogenase (FDH) by using amperometry, spectrophotometry, and circular dichroism (CD). (chromoscience.com)
  • Furthermore, we showed that the endogenous TRPM7-like current, which is known as Mg 2+ -inhibitable cation current (MIC) or Mg nucleotide-regulated metal ion current (MagNuM) in rat basophilic leukemia (RBL) cells was also significantly potentiated by acidic pH, suggesting that MIC/MagNuM is encoded by TRPM7. (rupress.org)
  • Crystallographic parameters and especially exchangeable cation site coordinates were refined for all samples with the Rietveld method. (elsevier.com)
  • The observed changes include a shift in cation sites Cs2 and Cs3 toward channel walls and occupancy decrease in site Cs2. (elsevier.com)
  • The cation occupancy in both sites depends on the net charge on the protein which was varied by equilibrating crystals in the pH range 7-10. (proteopedia.org)
  • The folding of telomeres into G-quadruplex structures in the presence of monovalent cations (e.g. (uni-potsdam.de)
  • Moraetis, D , Christidis, GE & Peridikatsis, V 2007, ' Ion exchange equilibrium and structural changes in clinoptilolite irradiated with β- and γ-radiation: Monovalent cations ', American Mineralogist , vol. 92, no. 10, pp. 1714-1730. (elsevier.com)
  • The features of monovalent cation and divalent metal activation, as well as the inhibition by Zn 2+ and Cd 2+ , are discussed in light of the kinetic and structural information available for MtIPMS and other relevant enzymes. (elsevier.com)