Elucidation of a pH-folding switch in the Pseudomonas syringae effector protein AvrPto.

ABSTRACT: Pathogenic bacteria have developed extraordinary strategies for invading host cells. The highly conserved type III secretion system (T3SS) provides a regulated conduit between the bacterial and host cytoplasm for delivery of a specific set of bacterial effector proteins that serve to disrupt host signaling and metabolism for the benefit of the bacterium. Remarkably, the inner diameter of the T3SS apparatus requires that effector proteins pass through in at least a partially unfolded form. AvrPto, an effector protein of the plant pathogen Pseudomonas syringae, adopts a helical bundle fold of low stability (DeltaG(F-->U) = 2 kcal/mol at pH 7, 26.6 degrees C) and offers a model system for chaperone-independent secretion. P. syringae effector proteins encounter a pH gradient as they translocat

SUBMITTER: Dawson JE 

PROVIDER: S-EPMC2689006 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature