The type III secretion chaperone SycE promotes a localized disorder-to-order transition in the natively unfolded effector YopE.

ABSTRACT: Many virulence-related, bacterial effector proteins are translocated directly into the cytosol of host cells by the type III secretion (TTS) system. Translocation of most TTS effectors requires binding by specific chaperones in the bacterial cytosol, although how chaperones promote translocation is unclear. To provide insight into the action of such chaperones, we studied the consequences of binding by the Yersinia chaperone SycE to the effector YopE by NMR. These studies examined the intact form of the effector, whereas prior studies have been limited to well ordered fragments. We found that YopE had the characteristics of a natively unfolded protein, with its N-terminal 100 residues, including its chaperone-binding (Cb) region, flexible and disordered in the absence of SycE. SycE binding

SUBMITTER: Rodgers L 

PROVIDER: S-EPMC2475703 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature