Forms part of the oxidative pyrimidine-degrading pathway in some microorganisms, along with EC 3.5.2.1 (barbiturase) and EC 3.5.1.95 (N-malonylurea hydrolase). Mammals, plants and other microorganisms utilize the reductive pathway, comprising EC 1.3.1.1 [dihydrouracil dehydrogenase (NAD+)] or EC 1.3.1.2 [dihydropyrimidine dehydrogenase (NADP+)], EC 3.5.2.2 (dihydropyrimidinase) and EC 3.5.1.6 (beta-ureidopropionase), with the ultimate degradation products being an L-amino acid, NH3 and CO2 [5].
History
EC 1.17.99.4 created 1961 as EC 1.2.99.1, transferred 1984 to EC 1.1.99.19, transferred 2006 to EC 1.17.99.4
Novel amidohydrolytic reactions in oxidative pyrimidine metabolism: analysis of the barbiturase reaction and discovery of a novel enzyme, ureidomalonase.