title: Crystal structure of the hexameric traffic ATPase of the Helicobacter pylori type IV secretion system.
abstract: The type IV secretion system of Helicobacter pylori consists of 10--15 proteins responsible for transport of the transforming protein CagA into target epithelial cells. Secretion of CagA crucially depends on the hexameric ATPase, HP0525, a member of the VirB11-PulE family. We present the crystal structure of a binary complex of HP0525 bound to ADP. Each monomer consists of two domains formed by the N- and C-terminal halves of the sequence. ADP is bound at the interface between the two domains. In the hexamer, the N- and C-terminal domains form two rings, which together form a chamber open on one side and closed on the other. A model is proposed in which HP0525 functions as an inner membrane pore, the closure and opening of which is regulated by ATP binding and ADP release.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: H J
authors.initials: HJ
authors.lastname: Yeo
authors.forename: S N
authors.initials: SN
authors.lastname: Savvides
authors.forename: A B
authors.initials: AB
authors.lastname: Herr
authors.forename: E
authors.initials: E
authors.lastname: Lanka
authors.forename: G
authors.initials: G
authors.lastname: Waksman
mesh_terms: D000244:Adenosine Diphosphate / Q000737:chemistry / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D000942:Antigens, Bacterial; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D016480:Helicobacter pylori / Q000201:enzymology* / Q000378:metabolism / Q000472:pathogenicity; D006860:Hydrogen Bonding; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D008954:Models, Biological; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D021122:Protein Subunits; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D037521:Virulence Factors
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D008565:Membrane Proteins; D021122:Protein Subunits; D011994:Recombinant Proteins; D037521:Virulence Factors; C080866:cagA protein, Helicobacter pylori; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases