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Structural and functional studies indicate that the EPEC effector, EspG, directly binds p21-activated kinase.

ABSTRACT: Bacterial pathogens secrete effectors into their hosts that subvert host defenses and redirect host processes. EspG is a type three secretion effector with a disputed function that is found in enteropathogenic Escherichia coli. Here we show that EspG is structurally similar to VirA, a Shigella virulence factor; EspG has a large, conserved pocket on its surface; EspG binds directly to the amino-terminal inhibitory domain of human p21-activated kinase (PAK); and mutations to conserved residues in the surface pocket disrupt the interaction with PAK.

SUBMITTER: Germane KL

PROVIDER: S-EPMC3040069 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Structural and functional studies indicate that the EPEC effector, EspG, directly binds p21-activated kinase.

Germane Katherine L KL Spiller Benjamin W BW

Biochemistry 20110124 6

Bacterial pathogens secrete effectors into their hosts that subvert host defenses and redirect host processes. EspG is a type three secretion effector with a disputed function that is found in enteropathogenic Escherichia coli. Here we show that EspG is structurally similar to VirA, a Shigella virulence factor; EspG has a large, conserved pocket on its surface; EspG binds directly to the amino-terminal inhibitory domain of human p21-activated kinase (PAK); and mutations to conserved residues in ...[more]

PMID: 21235237

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