title: Urease from Staphylococcus saprophyticus: purification, characterization and comparison to Staphylococcus xylosus urease.
abstract: Urease from Staphylococcus saprophyticus was purified more than 800-fold by liquid chromatography reaching homogeneity, as shown by isoelectric focussing, at a maximum specific activity of 1979 U/mg. The molecular weight of the native enzyme was 420,000; it consisted of subunits with molecular weights of 72,400 (alpha), 20,400 (beta), 13,900 (gamma) in an estimated (alpha beta gamma)4 stoichiometry. In native gradient polyacrylamide gel electrophoresis urease exhibited a multiple activity band pattern with molecular weights ranging from 420,000 to 100,000. In the native enzyme, 4.09 (+/- 0.25) atoms of nickel per molecule were detected. The N-terminal amino acids of the urease subunits were identical to those from Staphylococcus xylosus, and amino acid analysis revealed high similarities in both enzymes; no cysteine was detected after acid hydrolysis of vinylpyridinylated urease. Electron micrographs of negatively stained urease specimens from both staphylococci showed identical size and structure.
authors.affiliation: Lehrstuhl für Mikrobiologie, Universität des Saarlandes, Saarbrücken, Germany.
authors.forename: U K
authors.initials: UK
authors.lastname: Schäfer
authors.forename: H
authors.initials: H
authors.lastname: Kaltwasser
mesh_terms: D000595:Amino Acid Sequence; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009532:Nickel / Q000032:analysis; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D013210:Staphylococcus / Q000201:enzymology*; D014510:Urease / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D009532:Nickel; D014510:Urease