title: Nickel-binding properties of the C-terminal tail peptide of Bacillus pasteurii UreE.
abstract: Urease activation, which is critical to the virulence of many human and animal pathogens, is mediated by several accessory proteins. UreE, the only nickel-binding protein among the urease accessory proteins, catalyzes the activation of urease by transporting nickel ions into the urease active sites. The nickel-binding properties of UreE are still not clear, particularly for the protein from Bacillus pasteurii (Bp). Since the flexible C-terminal tail of BpUreE possesses two conserved histidines, the nickel-binding properties of the tail peptide were examined by circular dichroism spectroscopy, size-exclusion chromatography, and nuclear magnetic resonance spectroscopy. Specific nickel binding leading to alteration of the peptide backbone geometry was clearly observed. Side-chains of the two conserved histidines were identified as the main ligands for nickel coordination. The peptide became dimerized upon nickel binding and the binding stoichiometry was estimated as 1 equivalent of nickel per peptide dimer. Altogether, it is postulated that the C-terminal tail of BpUreE contributes to the nickel binding of the protein in different ways between the dimeric and tetrameric protein folds.
authors.affiliation: National Research Laboratory (MPS), Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, San 56-1, Shillim-Dong, Kwanak-Gu, Seoul 151-742, South Korea.
authors.forename: Hyung-Sik
authors.initials: HS
authors.lastname: Won
authors.forename: Bong-Jin
authors.initials: BJ
authors.lastname: Lee
mesh_terms: D001407:Bacillus / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry*; D002352:Carrier Proteins / Q000737:chemistry*; D002384:Catalysis; D002850:Chromatography, Gel / Q000379:methods; D002942:Circular Dichroism; D009682:Magnetic Resonance Spectroscopy; D009532:Nickel / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D014510:Urease / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D010455:Peptides; C090404:UreE protein, Bacteria; D009532:Nickel; D014510:Urease