title: Creatinine deiminase (EC 3.5.4.21) from bacterium BN11: purification, properties and applicability in a serum/urine creatinine assay.
abstract: Creatinine deiminase (EC 3.5.4.21) from the anaerobic microorganism BN11 has been purified to homogeneity by ammonium sulfate fractionation, gel filtration on Sephacryl-S-300 superfine and chromatography on DEAE-Sepharose C1 6B. The final enzyme preparation had a specific activity of 78 units per mg protein. Analysis of creatinine deiminase by polyacrylamide gradient gel electrophoresis and fast-flow-liquid-chromatography gave a relative molecular mass of 285 kDa and 288 kDa, respectively. By treatment with sodium dodecylsulfate and 2-mercaptoethanol creatinine deiminase was dissociated yielding one polypeptide with a relative molecular mass of 47.5 kDa. The enzyme was entirely specific for creatinine and showed a Km value of 0.15 mM. Creatinine deiminase was used to determine the concentration of creatinine in serum and urine using a manual method and an automated system.
authors.affiliation: Zentrum Innere Medizin, Georg-August-Universität Göttingen, FRG.
authors.forename: E M
authors.initials: EM
authors.lastname: Gottschalk
authors.forename: H
authors.initials: H
authors.lastname: Hippe
authors.forename: F
authors.initials: F
authors.lastname: Patzke
mesh_terms: D000619:Aminohydrolases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D000645:Ammonium Sulfate; D001322:Autoanalysis / Q000379:methods; D001421:Bacteria, Anaerobic / Q000201:enzymology*; D002845:Chromatography; D003013:Clostridium / Q000201:enzymology; D003404:Creatinine / Q000032:analysis* / Q000097:blood / Q000652:urine; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D005051:Eubacterium / Q000201:enzymology; D005590:Fractional Precipitation; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D003404:Creatinine; D000619:Aminohydrolases; C023157:creatinine deiminase; D000645:Ammonium Sulfate