Mechanics of proteins with a focus on atomic force microscopy

Journal of Nanobiotechnology

Tutorial

Laura Picas¹  Simon Scheuring²  Annafrancesca Rigato²  Felix Rico² 

[1] Institut Curie, UMR144 CNRS, 26 rue d'Ulm, 75005, Paris, France;U1006 INSERM, Aix-Marseille Université, Parc Scientifique de Luminy, 13009, Marseille, France;

关键词: Atomic Force Microscopy;    Nuclear Magnetic Resonance Spectroscopy;    Force Spectroscopy;    Protein Flexibility;    Free Energy Landscape;   

DOI  :  10.1186/1477-3155-11-S1-S3

来源: Springer

【 摘 要 】

The capacity of proteins to function relies on a balance between molecular stability to maintain their folded state and structural flexibility allowing conformational changes related to biological function. Among many others, four different examples can be chosen. The giant protein titin is stretched and can unfold during muscle contraction providing passive elasticity to muscle tissue; myoglobin adsorbs and releases oxygen molecules thank to conformational changes in its structure; the outer membrane protein G (OmpG) is a bacterial porin with a long and flexible loop that modulates gating; and the proton pump bacteriorhodopsin adapts its cytosolic half to allow proton pumping. All these conformational changes triggered either by chemical or by physical cues, require mechanical flexibility or elasticity of certain protein domains. While the methods to determine protein structure, X-ray crystallography above all, have been dramatically improved over the last decades, the number of tools that directly measure the mechanical flexibility of proteins and protein domains is still limited. In this tutorial, after a brief introduction to protein structure, we present some of the available techniques to estimate protein flexibility, then focusing on atomic force microscopy (AFM). We describe the principles of the technique and its various imaging and force spectroscopy modes of operation that allow probing the elasticity of proteins, protein domains and their surrounding environment.

【 授权许可】

CC BY   
© Rico et al.; licensee BioMed Central Ltd. 2013