Crystal structure of the passenger domain of the Escherichia coli autotransporter EspP.

ABSTRACT: Autotransporters represent a large superfamily of known and putative virulence factors produced by Gram-negative bacteria. They consist of an N-terminal "passenger domain" responsible for the specific effector functions of the molecule and a C-terminal "?-domain" responsible for translocation of the passenger across the bacterial outer membrane. Here, we present the 2.5-Å crystal structure of the passenger domain of the extracellular serine protease EspP, produced by the pathogen Escherichia coli O157:H7 and a member of the serine protease autotransporters of Enterobacteriaceae (SPATEs). Like the previously structurally characterized SPATE passenger domains, the EspP passenger domain contains an extended right-handed parallel ?-helix preceded by an N-terminal globular domain housing the catalytic function of the protease. Of note, however, is the absence of a second globular domain protruding from this ?-helix. We describe the structure of the EspP passenger domain in the context of previous results and provide an alternative hypothesis for the function of the ?-helix within SPATEs.

SUBMITTER: Khan S 

PROVIDER: S-EPMC3215816 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature