title: Occurrence of two distinct succinate thiokinases in animal tissues.
abstract: Although succinate thiokinase from mammalian sources has hitherto been described as showing substrate specificity for guanine nucleotide, a range of mammalian tissues has here been found to display succinate thiokinase activity with both guanine and adenine nucleotides as substrates. Evidence is presented for the existence of two distinct succinate thiokinases and this is confirmed by their separation by affinity chromatography. Each enzyme is specific for one nucleotide and is inhibited by the non-substrate nucleotide. The physiological roles of the two enzymes is yet to be established.
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002417:Cattle; D002846:Chromatography, Affinity; D003066:Coenzyme A Ligases / Q000302:isolation & purification*; D006153:Guanosine Diphosphate / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism; D008928:Mitochondria / Q000201:enzymology; D012756:Sheep; D013379:Substrate Specificity; D013389:Succinate-CoA Ligases / Q000302:isolation & purification*; D013552:Swine
chemical_list: D006153:Guanosine Diphosphate; D000244:Adenosine Diphosphate; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D003066:Coenzyme A Ligases; D013389:Succinate-CoA Ligases