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Autotransporter structure reveals intra-barrel cleavage followed by conformational changes.

ABSTRACT: Autotransporters are virulence factors produced by Gram-negative bacteria. They consist of two domains, an N-terminal 'passenger' domain and a C-terminal beta-domain. beta-domains form beta-barrel structures in the outer membrane while passenger domains are translocated into the extracellular space. In some autotransporters, the two domains are separated by proteolytic cleavage. Using X-ray crystallography, we solved the 2.7-A structure of the post-cleavage state of the beta-domain of EspP, an autotransporter produced by Escherichia coli strain O157:H7. The structure consists of a 12-stranded beta-barrel with the passenger domain-beta-domain cleavage junction located inside the barrel pore, approximately midway between the extracellular and periplasmic surfaces of the outer membrane. The structure reveals an unprecedented intra-barrel cleavage mechanism and suggests that two conformational changes occur in the beta-domain after cleavage, one conferring increased stability on the beta-domain and another restricting access to the barrel pore.

SUBMITTER: Barnard TJ

PROVIDER: S-EPMC2551741 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature

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Autotransporter structure reveals intra-barrel cleavage followed by conformational changes.

Barnard Travis J TJ Dautin Nathalie N Lukacik Petra P Bernstein Harris D HD Buchanan Susan K SK

Nature structural & molecular biology 20071111 12

Autotransporters are virulence factors produced by Gram-negative bacteria. They consist of two domains, an N-terminal 'passenger' domain and a C-terminal beta-domain. beta-domains form beta-barrel structures in the outer membrane while passenger domains are translocated into the extracellular space. In some autotransporters, the two domains are separated by proteolytic cleavage. Using X-ray crystallography, we solved the 2.7-A structure of the post-cleavage state of the beta-domain of EspP, an a ...[more]

PMID: 17994105

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Autotransporter structure reveals intra-barrel cleavage followed by conformational changes.

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Autotransporter structure reveals intra-barrel cleavage followed by conformational changes.

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