Lipid bilayers: thermodynamics, structure, fluctuations, and interactions

Lipid bilayers: thermodynamics, structure, fluctuations, and interactions.

This article, adapted from our acceptance speech of the Avanti Award in Lipids at the 47th Biophysical Society meeting in San Antonio, 2003, summarizes over 30 years of research in the area of lipid bilayers. Beginning with a theoretical model of the phase transition (J.F.N.), we have proceeded experimentally using dilatometry and density centrifugation to study volume, differential scanning ca...

Structure and Interactions of Lipid Bilayers: Role of Fluctuations

Composition Fluctuations in Lipid Bilayers.

Cell membranes contain multiple lipid and protein components having heterogeneous in-plane (lateral) distribution. Nanoscale rafts are believed to play an important functional role, but their phase state-domains of coexisting phases or composition fluctuations-is unknown. As a step toward understanding lateral organization of cell membranes, we investigate the difference between nanoscale domai...

Method for obtaining structure and interactions from oriented lipid bilayers.

Precise calculations are made of the scattering intensity I(q) from an oriented stack of lipid bilayers using a realistic model of fluctuations. The quantities of interest include the bilayer bending modulus Kc, the interbilayer interaction modulus B, and bilayer structure through the form factor F(qz). It is shown how Kc and B may be obtained from data at large q(z) where fluctuations dominate...

Structure of lipid bilayers.

The quantitative experimental uncertainty in the structure of fully hydrated, biologically relevant, fluid (L(alpha)) phase lipid bilayers has been too large to provide a firm base for applications or for comparison with simulations. Many structural methods are reviewed including modern liquid crystallography of lipid bilayers that deals with the fully developed undulation fluctuations that occ...