Two molecular forms of thymidine kinase in the cytosol of regenerating rat liver.
Two forms (Peak A and Peak B) of thymidine kinase [EC 2.7.1.75] from regenerating rat liver cytosol were resolved and partially purified by Deae-cellulose chromatography. Both fractions were identical with respect to their substrate requirement, pH optima, metal requirements, and molecular weight, as judged by their sedimentation in sucrose density gradient centrifugation. Peak B differed from Peak A in heat sensitivity, inhibition by dCTP and Km for thymidine and ATP. Peak B enzyme was the only enzyme found in normal adult liver and Peak A enzyme was the form increasing predominantly in regenerating liver.
D000818:Animals; D002413:Cations, Divalent; D003600:Cytosol / Q000201:enzymology; D004789:Enzyme Activation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008115:Liver Regeneration; D008274:Magnesium / Q000494:pharmacology; D008297:Male; D008930:Mitochondria, Liver / Q000201:enzymology; D051381:Rats; D013347:Subcellular Fractions / Q000201:enzymology; D013696:Temperature; D013937:Thymidine Kinase / Q000302:isolation & purification / Q000378:metabolism*
D002413:Cations, Divalent; D007527:Isoenzymes; D013937:Thymidine Kinase; D008274:Magnesium