title: Crystal structure of Helicobacter pylori neutrophil-activating protein with a di-nuclear ferroxidase center in a zinc or cadmium-bound form.
abstract: Helicobacter pylori neutrophil-activating protein (HP-NAP) is a Dps-like iron storage protein forming a dodecameric shell, and promotes adhesion of neutrophils to endothelial cells. The crystal structure of HP-NAP in a Zn(2+)- or Cd(2+)-bound form reveals the binding of two zinc or two cadmium ions and their bridged water molecule at the ferroxidase center (FOC). The two zinc ions are coordinated in a tetrahedral manner to the conserved residues among HP-NAP and Dps proteins. The two cadmium ions are coordinated in a trigonal-bipyramidal and distorted octahedral manner. In both structures, the second ion is more weakly coordinated than the first. Another zinc ion is found inside of the negatively-charged threefold-related pore, which is suitable for metal ions to pass through.
authors.affiliation: School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan. h-yokoya@u-shizuoka-ken.ac.jp
authors.forename: Hideshi
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Osamu
authors.initials: O
authors.lastname: Tsuruta
authors.forename: Naoya
authors.initials: N
authors.lastname: Akao
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fujii
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D002104:Cadmium / Q000737:chemistry*; D002570:Ceruloplasmin / Q000737:chemistry*; D018360:Crystallography, X-Ray; D011487:Protein Conformation; D015032:Zinc / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; C092412:neutrophil-activating protein A, Helicobacter pylori; D002104:Cadmium; D002570:Ceruloplasmin; D015032:Zinc