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PubMed · 8042901

Urease from Staphylococcus saprophyticus: purification, characterization and comparison to Staphylococcus xylosus urease.

U K Schäfer·H Kaltwasser
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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.

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Amino Acid SequenceMicroscopy, ElectronMolecular Sequence DataNickelSequence Homology, Amino AcidSpecies SpecificityStaphylococcusUreaseComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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U K Schäfer, H Kaltwasser. 1994. Urease from Staphylococcus saprophyticus: purification, characterization and comparison to Staphylococcus xylosus urease.. https://doi.org/10.1007/bf00288948

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