Thermoelastic properties of SOPC:POPE bilayers and lipid:cholesterol mixtures

Range Table - link
Organism Generic
Reference Evan. Evans, David. Needham, Physical properties of surfactant bilayer membranes: thermal transitions, elasticity, rigidity, cohesion and colloidal interactions. J. Phys. Chem., 1987, 91 (16), pp 4219–4228 DOI: 10.1021/j100300a003 link p.4224 tables I and II
Method P.4219 left column bottom paragraph: "In this article, [investigators] discuss how mixtures of lipids, cholesterol, and polypeptides affect the thermal-mechanical and colloidal interaction properties of bilayer membranes. [They] outline prominent physical features of bilayer membrane materials as solid and liquid surface structures. [They] examine how amphiphilic mixtures influence membrane cohesion and colloidal attraction. Finally, [they] evaluate the efficacy of classical prescriptions for van der Waals attraction and electric double-layer repulsion to correlate measured free energy potentials for adhesion. Lipids from two classes are discussed: phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidylglycerol (PG)) and a “sugar” lipid (digalactosyl diacyl glycerol (DGDG)). The former are ubiquitous constituents of animal cell membranes whereas the latter exists predominantly in plant cell membranes."
Comments p.4224 left column bottom paragraph: "Values for area compressibility moduli, measured at temperatures just above the main transition in the Lα phase of both components, show a slight linear compositional dependence (Table I) consistent with ideal mixing. Thermal area expansivities for the mixtures are similar to values for the single components in the Lα phase when well above the acyl chain crystallization temperature. Based on observation of the tensions required to lyse (rupture) vesicles, these neutral lipid mixtures exhibit bilayer cohesion levels similar to single-component membranes." SOPC=1-stearoyl-2-oleoylphosphatidylcholine. POPE=1-palmitoyl-2-oleoylphosphatidylethanolamine. DMPC=dimyristoylphosphatidylcholine
Entered by Uri M
ID 112589