[Purification and properties of a catalytically active fragment of soluble nucleoside triphosphatase from bovine kidney].
A catalytic fragment of soluble NTPase has been isolated from bovine kidneys.The 236-fold purification was carried out to obtain the preparation with a specific activity of 37.7 U/mg of protein. The purification scheme included the enzyme extraction followed by four column chromatography steps. The catalytic fragment was activated with divalent metal ions, had a pH optimum of 7.0, and possessed specificity for ITP, GTP, UTP and XTP. The apparent K(m) for Mg-ITP, Mg-GTP and Mg-UTP complexes were calculated from Hanes plots to be 1.70 mM, 0.93 mM and 0.48 mM, respectively. As estimated by gel filtration and SDS-PAAGE, the catalytic fragment has Mw 54.7 kDa being composed of two identical polypeptide chains. Our results suppose soluble NTPase from bovine kidney to consist of regulatory and catalytic structural units.
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Makarchikov
D000818:Animals; D055162:Biocatalysis; D002413:Cations, Divalent / Q000737:chemistry; D002417:Cattle; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D006160:Guanosine Triphosphate / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007293:Inosine Triphosphate / Q000737:chemistry; D007668:Kidney / Q000737:chemistry* / Q000201:enzymology; D007700:Kinetics; D043583:Nucleoside-Triphosphatase / Q000737:chemistry* / Q000302:isolation & purification; D010446:Peptide Fragments / Q000737:chemistry* / Q000302:isolation & purification; D021122:Protein Subunits / Q000737:chemistry* / Q000302:isolation & purification; D012265:Ribonucleotides / Q000737:chemistry; D012995:Solubility; D013379:Substrate Specificity; D014544:Uridine Triphosphate / Q000737:chemistry
D002413:Cations, Divalent; D010446:Peptide Fragments; D021122:Protein Subunits; D012265:Ribonucleotides; D007293:Inosine Triphosphate; C065326:xanthosine 5'-triphosphate; D006160:Guanosine Triphosphate; D043583:Nucleoside-Triphosphatase; D014544:Uridine Triphosphate