title: Crystal structures of apo and metal-bound forms of the UreE protein from Helicobacter pylori: role of multiple metal binding sites.
abstract: The crystal structure of the urease maturation protein UreE from Helicobacter pylori has been determined in its apo form at 2.1 A resolution, bound to Cu(2+) at 2.7 A resolution, and bound to Ni(2+) at 3.1 A resolution. Apo UreE forms dimers, while the metal-bound enzymes are arranged as tetramers that consist of a dimer of dimers associated around the metal ion through coordination by His102 residues from each subunit of the tetramer. Comparison of independent subunits from different crystal forms indicates changes in the relative arrangement of the N- and C-terminal domains in response to metal binding. The improved ability of engineered versions of UreE containing hexahistidine sequences at either the N-terminal or C-terminal end to provide Ni(2+) for the final metal sink (urease) is eliminated in the H102A version. Therefore, the ability of the improved Ni(2+)-binding versions to deliver more nickel is likely an effect of an increased local concentration of metal ions that can rapidly replenish transferred ions bound to His102.
authors.affiliation: Department of Biochemistry, McGill University, Montreal, Quebec, Canada H3G 1Y6.
authors.forename: Rong
authors.initials: R
authors.lastname: Shi
authors.forename: Christine
authors.initials: C
authors.lastname: Munger
authors.forename: Abdalin
authors.initials: A
authors.lastname: Asinas
authors.forename: Stéphane L
authors.initials: SL
authors.lastname: Benoit
authors.forename: Erica
authors.initials: E
authors.lastname: Miller
authors.forename: Allan
authors.initials: A
authors.lastname: Matte
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Maier
authors.forename: Miroslaw
authors.initials: M
authors.lastname: Cygler
mesh_terms: D001051:Apoenzymes / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D003300:Copper / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D016480:Helicobacter pylori / Q000201:enzymology*; D008958:Models, Molecular; D009532:Nickel / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D055503:Protein Multimerization
chemical_list: D001051:Apoenzymes; D001426:Bacterial Proteins; D002352:Carrier Proteins; C090404:UreE protein, Bacteria; D003300:Copper; D009532:Nickel