Conformational Chaperones for Structural Studies of Membrane Proteins Using Antibody Phage Display with Nanodiscs

Dominik PK, Borowska MT, Dalmas O, Kim SS, Perozo E, Keenan RJ, Kossiakoff AA

Structure 2016 Feb;24(2):300-9

PMID: 26749445

Abstract

A major challenge in membrane biophysics is to define the mechanistic linkages between a protein’s conformational transitions and its function. We describe a novel approach to stabilize transient functional states of membrane proteins in native-like lipid environments allowing for their structural and biochemical characterization. This is accomplished by combining the power of antibody Fab-based phage display selection with the benefits of embedding membrane protein targets in lipid-filled nanodiscs. In addition to providing a stabilizing lipid environment, nanodiscs afford significant technical advantages over detergent-based formats. This enables the production of a rich pool of high-performance Fab binders that can be used as crystallization chaperones, as fiducial markers for single-particle cryoelectron microscopy, and as probes of different conformational states. Moreover, nanodisc-generated Fabs can be used to identify detergents that best mimic native membrane environments for use in biophysical studies.