Study of Lipid Membranes Interaction With Cholesterol and Functional Peptides

Abstract

Cellular membranes are important targets for many membrane-active peptides and drug compounds. Here we are interested in deciphering how lipid membranes are perturbed by several membrane-active molecules, such as cholesterol and crucial peptides such as α- amylase. We employ phase-separated ternary lipid model membranes in the form of giant unilamellar vesicles (GUVs) to simulate raft-like structures that have been proposed to gov- ern many important processes in plasma membranes (e.g., intracellular singling and traf- ficking). Specifically, we use phase contrast microscopy to interrogate how those membrane additives modulate the phase behaviour of free-standing GUVs and the bending rigidity of the membranes. We quantify these changes in the bending rigidity of the lipid membrane and predict cellular characteristics.