Reaction: barbiturate + H2O = 3-oxo-3-ureidopropanoate
For diagram, click here
Glossary: barbiturate = 6-hydroxyuracil
Systematic name: barbiturate amidohydrolase (3-oxo-3-ureidopropanoate-forming)
Comments: Contains zinc and is specific for barbiturate as substrate [3]. Forms part of the oxidative pyrimidine-degrading pathway in some microorganisms, along with EC 1.17.99.4 (uracil/thymine dehydrogenase) and EC 3.5.1.95 (N-malonylurea hydrolase). It was previously thought that the end-products of the reaction were malonate and urea but this has since been disproved [2]. May be involved in the regulation of pyrimidine metabolism, along with EC 2.4.2.9, uracil phosphoribosyltransferase.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9025-16-5
References:
1. Hayaishi, O. and Kornberg, A. Metabolism of cytosine, thymine, uracil, and barbituric acid by bacterial enzymes. J. Biol. Chem. 197 (1952) 717-723. [PMID: 12981104]
2. Soong, C.L., Ogawa, J. and Shimizu, S. Novel amidohydrolytic reactions in oxidative pyrimidine metabolism: analysis of the barbiturase reaction and discovery of a novel enzyme, ureidomalonase. Biochem. Biophys. Res. Commun. 286 (2001) 222-226. [PMID: 11485332]
3. Soong, C.L., Ogawa, J., Sakuradani, E. and Shimizu, S. Barbiturase, a novel zinc-containing amidohydrolase involved in oxidative pyrimidine metabolism. J. Biol. Chem. 277 (2002) 7051-7058. [PMID: 11748240]