2qom

Publication Abstract from PubMed

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.

Autotransporter structure reveals intra-barrel cleavage followed by conformational changes.,Barnard TJ, Dautin N, Lukacik P, Bernstein HD, Buchanan SK Nat Struct Mol Biol. 2007 Dec;14(12):1214-20. Epub 2007 Nov 11. PMID:17994105^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.