Post-expression strategies for structural investigations of membrane proteins. (June 2015)

• Record Type: Journal Article
• Authors: Columbus, Linda
• Is Part Of: Current opinion in structural biology. Volume 32(2015)
• Page Start: 131
• Page End: 138
• Publication Date: 2015-06
• Subjects: Molecular biology -- Periodicals; 570
• DOI: 10.1016/j.sbi.2015.04.005
• Languages: English
• ISSNs: 0959-440X

Abstract

Highlights: Post-expression modifications have enabled membrane protein structure determination. Limited proteolysis removes flexible regions. Deglycosylation removes heterogeneous post-translational modifications. Cysteine alkylation prevents disulfide dimers and higher order oligomers. Other modifications allow the structure determination of alternative conformations. Abstract : Currently, membrane proteins only comprise 1.5% of the protein data bank and, thus, still remain a challenge for structural biologists. Expression, stabilization in membrane mimics (e.g. detergent), heterogeneity (conformational and chemical), and crystallization in the presence of a membrane mimic are four major bottlenecks encountered. In response, several post-expression protein modifications have been utilized to facilitate structure determination of membrane proteins. This review highlights four approaches: limited proteolysis, deglycosylation, cysteine alkylation, and lysine methylation. Combined these approaches have facilitated the structure determination of more than 40 membrane proteins and, therefore, are a useful addition to the membrane protein structural biologist's toolkit.