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Crystal structure of the C-terminal domain of the Salmonella type III secretion system export apparatus protein InvA.

ABSTRACT: InvA is a prominent inner-membrane component of the Salmonella type III secretion system (T3SS) apparatus, which is responsible for regulating virulence protein export in pathogenic bacteria. InvA is made up of an N-terminal integral membrane domain and a C-terminal cytoplasmic domain that is proposed to form part of a docking platform for the soluble export apparatus proteins notably the T3SS ATPase InvC. Here, we report the novel crystal structure of the C-terminal domain of Salmonella InvA which shows a compact structure composed of four subdomains. The overall structure is unique although the first and second subdomains exhibit structural similarity to the peripheral stalk of the A/V-type ATPase and a ring building motif found in other T3SS proteins respectively.

SUBMITTER: Worrall LJ

PROVIDER: S-EPMC2868250 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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Crystal structure of the C-terminal domain of the Salmonella type III secretion system export apparatus protein InvA.

Worrall Liam J LJ Vuckovic Marija M Strynadka Natalie C J NC

Protein science : a publication of the Protein Society 20100501 5

InvA is a prominent inner-membrane component of the Salmonella type III secretion system (T3SS) apparatus, which is responsible for regulating virulence protein export in pathogenic bacteria. InvA is made up of an N-terminal integral membrane domain and a C-terminal cytoplasmic domain that is proposed to form part of a docking platform for the soluble export apparatus proteins notably the T3SS ATPase InvC. Here, we report the novel crystal structure of the C-terminal domain of Salmonella InvA wh ...[more]

PMID: 20306492

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