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Mining electron density for functionally relevant protein polysterism in crystal structures.

ABSTRACT: This review focuses on conceptual and methodological advances in our understanding and characterization of the conformational heterogeneity of proteins. Focusing on X-ray crystallography, we describe how polysterism, the interconversion of pre-existing conformational substates, has traditionally been analyzed by comparing independent crystal structures or multiple chains within a single crystal asymmetric unit. In contrast, recent studies have focused on mining electron density maps to reveal previously 'hidden' minor conformational substates. Functional tests of the importance of minor states suggest that evolutionary selection shapes the entire conformational landscape, including uniquely configured conformational substates, the relative distribution of these substates, and the speed at which the protein can interconvert between them. An increased focus on polysterism may shape the way protein structure and function is studied in the coming years.

SUBMITTER: Fraser JS

PROVIDER: S-EPMC3092063 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Mining electron density for functionally relevant protein polysterism in crystal structures.

Fraser James S JS Jackson Colin J CJ

Cellular and molecular life sciences : CMLS 20101229 11

This review focuses on conceptual and methodological advances in our understanding and characterization of the conformational heterogeneity of proteins. Focusing on X-ray crystallography, we describe how polysterism, the interconversion of pre-existing conformational substates, has traditionally been analyzed by comparing independent crystal structures or multiple chains within a single crystal asymmetric unit. In contrast, recent studies have focused on mining electron density maps to reveal pr ...[more]

PMID: 21190057

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