Interactions of Cymal-6 and Lipid Vesicles

Abstract

The solubilization of biological or liposomal membranes, induced by detergents and detergent-like biomolecules, is important to many technical applications and biological phenomena. In fact, the interactions of classical detergents with lipid bilayers are described and understood quite well. Recently, new types of detergents with cyclohexyl groups or branches in their hydrophobic tails have been synthesized and proposed to be superior for membrane protein studies. Cymal-6 has, for example, been used for isolating membrane proteins such as CCR5 and HIV-1 corepressors. Here we provide a rather comprehensive description of the interactions of Cymal-6 with fluid membranes of POPC. This includes the temperature-dependent phase behavior (i.e., the onset and completion of solubilization), membrane partitioning, disordering, and permeabilization as seen using ITC, time-resolved fluorescence anisotropy of DPH, dynamic light scattering, and the lifetime-based vesicle leakage assay.