The ionization and phase behavior of 1,2-dipalmitoyl-sn-glycero-3-phosphoserine have been investigated under a variety of condtions by several different methods. As measured by turbidity changes, the temperature of the crystal-liquid crystal phase transition of this lipid is influenced by pH and mono- and divalent cation concentrations. The pH-transition temperature curve is congruent with the curve relating temperature to the degree of ionization of the carboxyl group of the crystalline form. The transition temperature falls from an upper plateau of 72 degrees C at low pH values, where the carboxyl group is fully protonated, to a lower plateau of 55 degrees C at high pH values, where this group is fully ionized. The apparent pK (pH at 50% ionization) of the crystalline form shifts from 6.0 to 4.6 to 3.7 with an increase of NaCl concentration from 10(-3) to 0.1 to l.0 M, respectively. These observations are in accord with a simple theoretical analysis that utilizes diffuse double layer theory and the influence of surface potential on surface concentration of protons. In qualitative terms, an increase in electrolyte concentration reduces the surface potential, the result of which is a diminution of the surface-bulk pH differenc...Continue Reading
Phase transitions and phase separations in phospholipid membranes induced by changes in temperature, pH, and concentration of bivalent cations
Calorimetric and freeze-etch study of the influence of Mg2+ on the thermotropic behaviour of phosphatidylglycerol
Stabilities of metal complexes of phospholipids: Ca(II), Mg(II), and Ni(II) complexes of phosphatidylserine and triphosphoinositide
Surface properties of acidic phospholipids: interaction of monolayers and hydrated liquid crystals with uni- and bi-valent metal ions
The influence of pH, Ca2+ and protein on the thermotropic behaviour of the negatively charged phospholipid, phosphatidylglycerol
Thermal analysis of lipids, proteins and biological membranes. A review and summary of some recent studies
Na+ and H+ dependent Mn2+ binding to phosphatidylserine vesicles as a test of the Gouy-Chapman-Stern theory
Lateral phase separations in binary mixtures of phospholipids having different charges and different crystalline structures
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The influence of charge on bilayer membranes. Calorimetric investigations of phosphatidic acid bilayers
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The plasma membrane of yeast protoplasts exposed to hypotonicity becomes porous but does not disintegrate in the presence of protons or polyvalent cations
Effect of surface ionization of dimyristoylphosphatidic acid vesicle membranes on the main phase-transition enthalpy and temperature
Monolayer coupling in phosphatidylserine bilayers: distinct phase transitions induced by magnesium interacting with one or both monolayers
The enzymatic synthesis of phosphatidylserine and purification by CM-cellulose column chromatography
Importance of glycerol and fatty acid residues on the ionic properties of phosphatidylglycerols at the air-water interface
The use of differential scanning calorimetry and differential thermal analysis in studies of model and biological membranes
The pH dependence of headgroup and acyl chain structure and dynamics of phosphatidylserine, studied by 2H-NMR
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Ionization of phospholipids and phospholipid-supported interfacial lateral diffusion of protons in membrane model systems
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Temperature-dependent phase behavior of phosphatidylglycerols from chilling-sensitive and chilling-resistant plants
Electrostatic interactions at charged lipid membranes. Measurement of surface pH with fluorescent lipoid pH indicators
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Phospholipid structure determines the effects of peptides on membranes. Differential scanning calorimetry studies with pentagastrin-related peptides
Phase transitions in lipid bilayers. A theoretical model for phosphatidylethanolamine and phosphatidic acid bilayers
Sequestration of chelated copper by structural Fe(II): Reductive decomplexation and transformation of Cu(II)-EDTA
Maximally asymmetric transbilayer distribution of anionic lipids alters the structure and interaction with lipids of an amyloidogenic protein dimer bound to the membrane surface
In vitro and in vivo effect of Escherichia coli endotoxin on mitochondrial phospholipase A2 activity
Effect of lipid composition on the topography of membrane-associated hydrophobic helices: stabilization of transmembrane topography by anionic lipids
Effect of temperature and pH on 31P nuclear magnetic resonances of phospholipids in cholate micelles
The effect of pH on the electrical capacitance of phosphatidylcholine-phosphatidylserine system in bilayer lipid membrane
The effect of protons or calcium ions on the phase behavior of phosphatidylserine-cholesterol mixtures
Cholesterol sulfate and Ca(2+) modulate the mixing properties of lipids in stratum corneum model mixtures
Effect of pH and monovalent cations on the ionization state of phosphatidylglycerol in monolayers. An experimental (surface potential) and theoretical (Gouy-Chapman) approach
Effects of divalent cations, trypsin, and phospholipases on the passive permeability to sodium of inside-out vesicles from human red cells
Binding of human normal and multiple sclerosis-derived myelin basic protein to phospholipid vesicles: effects on membrane head group and bilayer regions
Effect of lipid phase transition on the binding of anions to dimyristoylphosphatidylcholine liposomes
Influence of metal ions on the phase properties of phosphatidic acid in combination with natural and synthetic phosphatidylcholines: an X-ray diffraction study using synchrotron radiation
Calorimetric and spectroscopic studies of the thermotropic phase behavior of lipid bilayer model membranes composed of a homologous series of linear saturated phosphatidylserines
Surface dipole potential at the interface between water and self-assembled monolayers of phosphatidylserine and phosphatidic acid
Effect of sphingosine and stearylamine on the interaction of phosphatidylserine with calcium. A study using DSC, FT-IR and 45Ca(2+)-binding
Investigation of phosphatidylethanolamine bilayers by deuterium and phosphorus-31 nuclear magnetic resonance
The hydrophobic adsorption of charged molecules to bilayer membranes: a test of the applicability of the stern equation
Titration of the phase transition of phosphatidylserine bilayer membranes. Effects of pH, surface electrostatics, ion binding, and head-group hydration
Fluorescence quenching in model membranes. 2. Determination of local lipid environment of the calcium adenosinetriphosphatase from sarcoplasmic reticulum
A theory of effect of protons and divalent cations on phase equilibria in charged bilayer membranes: comparison with experiment
Phosphorus-31 and carbon-13 nuclear magnetic resonance studies of divalent cation binding to phosphatidylserine membranes: use of cobalt as a paramagnetic probe
Head-group contributions to bilayer stability: monolayer and calorimetric studies on synthetic, stereochemically uniform glucolipids
Calcium ion binding between lipid bilayers: the four-component system of phosphatidylserine, phosphatidylcholine, calcium chloride, and water
Interactions of metal ions with phosphatidylserine bilayer membranes: effect of hydrocarbon chain unsaturation
The role of charge and hydrophobicity in peptide-lipid interaction: a comparative study based on tryptophan fluorescence measurements combined with the use of aqueous and hydrophobic quenchers
Structure and phase behavior of a charged glycolipid (1,2-O-dialkyl-3-O-beta-D-glucuronosyl-sn-glycerol)
Increase of radiation damage to potassium-ion permeability in E. coli cells with decrease in membrane fluidity
Membrane potential and electrostatics of phospholipid bilayers with asymmetric transmembrane distribution of anionic lipids
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