FLUCTUATIONS IN LIPID BILAYERS: ARE THEY UNDERSTOOD?

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...

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...

Tuning membrane thickness fluctuations in model lipid bilayers.

Membrane thickness fluctuations have been associated with a variety of critical membrane phenomena, such as cellular exchange, pore formation, and protein binding, which are intimately related to cell functionality and effective pharmaceuticals. Therefore, understanding how these fluctuations are controlled can remarkably impact medical applications involving selective macromolecule binding and...

Structure and Interactions of Lipid Bilayers: Role of Fluctuations

Lipid bilayers and membrane dynamics: insight into thickness fluctuations.

Thickness fluctuations have long been predicted in biological membranes but never directly observed experimentally. Here, we utilize neutron spin echo spectroscopy to experimentally reveal such fluctuations in a pure, fully saturated, phosphocholine lipid bilayer system. These fluctuations appear as an excess in the dynamics of undulation fluctuations. Like the bending rigidity, the thickness f...