Measurement of the lateral compressibility of several phospholipid bilayers (original) (raw)

1982, Biophysical journal

Lateral compressibilities of bilayers in multilayer lattices are given for 10 phospholipid preparation:dilauryl-, dimyristoyl-, dipalmitoyl-, distearoyl-, and dioleoylphosphatidylcholine (PC); egg phosphatidylethanolamine (PE); as well as cholesterol-containing bilayers of dipalmitoyl PC or of egg PC. Bilayer deformability is highly nonlinear and does not permit description in terms of a simple modulus. The presence of cholesterol or C=C bonds (dioleoyl PC) increases deformability, but freezing of acyl chains does not cause dramatic stiffening of the bilayer. Lateral compression of dilauryl PC an dimyristoyl PC causes a transition from "melted" to "frozen" acyl chains above the normal transition temperatures. Our measurements do not correspond in any obvious way to lateral compressibilities in monolayers at the air-water interface.

Effect of cholesterol on the structure of a phospholipid bilayer

Proceedings of the National Academy of Sciences of the United States of America, 2009

Cholesterol plays an important role in regulating the properties of phospholipid membranes. To obtain a detailed understanding of the lipid-cholesterol interactions, we have developed a mesoscopic water-lipid-cholesterol model. In this model, we take into account the hydrophobic-hydrophilic interactions and the structure of the molecules. We compute the phase diagram of dimyristoylphosphatidylcholine-cholesterol by using dissipative particle dynamics and show that our model predicts many of the different phases that have been observed experimentally. In quantitative agreement with experimental data our model also shows the condensation effect; upon the addition of cholesterol, the area per lipid decreases more than one would expect from ideal mixing. Our calculations show that this effect is maximal close to the main-phase transition temperature, the lowest temperature for which the membrane is in the liquid phase, and is directly related to the increase of this main-phase transitio...

Loading...

Loading Preview

Sorry, preview is currently unavailable. You can download the paper by clicking the button above.