2QOM: The Crystal Structure of the E.coli Espp Autotransporter Beta-domain

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.
PDB ID: 2QOMDownload
MMDB ID: 60568
PDB Deposition Date: 2007/7/20
Updated in MMDB: 2007/11 
Experimental Method:
x-ray diffraction
Resolution: 2.66  Å
Source Organism:
Similar Structures:
Biological Unit for 2QOM: monomeric; determined by author and by software (PQS)
Molecular Components in 2QOM
Label Count Molecule
Protein (1 molecule)
Serine Protease Espp
(Gene: espP)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB