2pt7
From Proteopedia
Crystal structure of Cag VirB11 (HP0525) and an inhibitory protein (HP1451)
Overview
Helicobacter pylori is one of the world's most successful human pathogens causing gastric ulcers and cancers. A key virulence factor of H. pylori is the Cag pathogenicity island, which encodes a type IV secretion system. HP0525 is an essential component of the Cag system and acts as an inner membrane associated ATPase. HP0525 forms double hexameric ring structures, with the C-terminal domains (CTDs) forming a closed ring and the N-terminal domains (NTDs) forming a dynamic, open ring. Here, the crystal structure of HP0525 in complex with a fragment of HP1451, a protein of previously unknown function, is reported. The HP1451 construct consists of two domains similar to nucleic acid-binding domains. Two HP1451 molecules bind to the HP0525 NTDs on opposite sides of the hexamer, locking it in the closed form and forming a partial lid over the HP0525 chamber. From the structure, it is suggested that HP1451 acts as an inhibitory factor of HP0525 to regulate Cag-mediated secretion, a suggestion confirmed by results of in vitro ATPase assay and in vivo pull-down experiments.
About this Structure
2PT7 is a Protein complex structure of sequences from Helicobacter pylori. Full crystallographic information is available from OCA.
Reference
Identification, structure and mode of action of a new regulator of the Helicobacter pylori HP0525 ATPase., Hare S, Fischer W, Williams R, Terradot L, Bayliss R, Haas R, Waksman G, EMBO J. 2007 Nov 28;26(23):4926-34. Epub 2007 Nov 1. PMID:17972918 Page seeded by OCA on Sun May 4 13:46:11 2008
