Enzymes and cancer. Preparation and some properties of guanase from rabbit liver.
1. Guanase has been purified 200-fold in 20% yield from the supernatant fraction of rabbit-liver homogenates, by using ammonium sulphate fractionation, calcium phosphate-gel adsorption and chromatography on DEAE-cellulose and Sephadex G-200. 2. K(m) with guanine as substrate at the optimum pH of 7.7 was found to be 1.05x10(-5)m. Q(10) was 1.4 between 23 degrees and 48 degrees . 3. Substrate activity and pH optima of compounds related to guanine have been studied. 8-Azaguanine, 1-methylguanine, thioguanine and 1-methylthioguanine are all substrates.
D000619:Aminohydrolases / Q000378:metabolism*; D000818:Animals; D011232:Chemical Precipitation; D002845:Chromatography; D002850:Chromatography, Gel; D006147:Guanine / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008099:Liver / Q000201:enzymology*; D009369:Neoplasms / Q000378:metabolism; D011817:Rabbits
D006147:Guanine; D000619:Aminohydrolases