Allosteric transitions in the chaperonin GroEL are captured by a dominant normal mode that is most robust to sequence variations.

ABSTRACT: The Escherichia coli chaperonin GroEL, which helps proteins to fold, consists of two heptameric rings stacked back-to-back. During the reaction cycle GroEL undergoes a series of allosteric transitions triggered by ligand (substrate protein, ATP, and the cochaperonin GroES) binding. Based on an elastic network model of the bullet-shaped double-ring chaperonin GroEL-(ADP)(7)-GroES structure (R''T state), we perform a normal mode analysis to explore the energetically favorable collective motions encoded in the R''T structure. By comparing each normal mode with the observed conformational changes in the R''T --> TR'' transition, a single dominant normal mode provides a simple description of this highly intricate allosteric transition. A detailed analysis of this relatively high-frequency mode

SUBMITTER: Zheng W 

PROVIDER: S-EPMC1965427 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature