Structural study of membrane proteins using vesicles

Abstract

Membrane proteins play crucial roles in numerous biological processes and are important drug targets. However, structural studies of memebrane proteins heavily rely on solubilization by detergents, which may not reflect their native states in the cellular context. Moreover, identifying suitable detergents for individual membrane proteins is a tedious and costly screening process. Here, we developed a vesicle-based method that enables membrane protein structure determination in their native lipid environment, thereby bypassing the limitations of detergent solubilization. Using this approach, we isolated vesicles containing the multidrug efflux transporter AcrB and solved its structure by cryo-electron microscopy. Intriguingly, the AcrB trimer in the vesicle exhibited a loose assembly compared to the detergent-solubilized and nanoparticle structures. Our method presents a promising approach for studying structure and function of membrane protein in their native environment without the need for detergent screening and protein purification.