title: Age dependent variations in choline and ethanolamine phosphorylating activities of rodents.
abstract: The substrate concentration-velocity relationship as influenced by age of animal was determined. At all stages of growth of rat and mouse ethanolamine kinase activity responded with a hyperbolic pattern to substrate concentration. Choline kinase on the other hand, underwent "enzyme differentiation". In rat liver up to 4 days of age of animal, in mouse liver up to 7 days and in mouse kidney up to 15 days, choline kinase activity responded with a hyperbolic pattern; but from then onwards the response to substrate concentration was sigmoid. The results obtained pointed to the regulatory nature of choline kinase and a possible distinction between the proteins catalyzing the phosphorylation of the two bases.
mesh_terms: D000375:Aging; D000818:Animals; D002794:Choline / Q000378:metabolism*; D002797:Choline Kinase / Q000378:metabolism; D019856:Ethanolamine; D004983:Ethanolamines / Q000378:metabolism*; D007668:Kidney / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D051379:Mice; D010766:Phosphorylation; D010770:Phosphotransferases / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor); D051381:Rats
chemical_list: D004983:Ethanolamines; D019856:Ethanolamine; D010770:Phosphotransferases; D017853:Phosphotransferases (Alcohol Group Acceptor); D002797:Choline Kinase; C020125:ethanolamine kinase; D002794:Choline