Uracil/thymine dehydrogenase

Uracil/thymine dehydrogenase (EC 1.17.99.4, uracil oxidase, uracil-thymine oxidase, uracil dehydrogenase) is an enzyme with systematic name uracil:acceptor oxidoreductase. This enzyme catalyses the following chemical reaction

(1) uracil + H₂O + acceptor

\rightleftharpoons

barbiturate + reduced acceptor

(2) thymine + H₂O + acceptor

\rightleftharpoons

5-methylbarbiturate + reduced acceptor

Uracil/thymine dehydrogenase forms part of the oxidative pyrimidine-degrading pathway in some microorganisms.

References

Hayaishi O, Kornberg A (May 1952). "Metabolism of cytosine, thymine, uracil, and barbituric acid by bacterial enzymes". The Journal of Biological Chemistry. 197 (2): 717–32. PMID 12981104.
Wang TP, Lampen JO (February 1952). "Metabolism of pyrimidines by a soil bacterium". The Journal of Biological Chemistry. 194 (2): 775–83. PMID 14927671.
Wang TP, Lampen JO (February 1952). "Uracil oxidase and the isolation of barbituric acid from uracil oxidation". The Journal of Biological Chemistry. 194 (2): 785–91. PMID 14927672.
Lara FJ (August 1952). "On the decomposition of pyrimidines by bacteria. II. Studies with cell-free enzyme preparations". Journal of Bacteriology. 64 (2): 279–85. PMC 169350. PMID 14955523.
Soong CL, Ogawa J, Shimizu S (August 2001). "Novel amidohydrolytic reactions in oxidative pyrimidine metabolism: analysis of the barbiturase reaction and discovery of a novel enzyme, ureidomalonase". Biochemical and Biophysical Research Communications. 286 (1): 222–6. doi:10.1006/bbrc.2001.5356. PMID 11485332.

v t e Other oxidoreductases (EC 1.15–1.21)
1.15: Acting on superoxide as acceptor	Superoxide dismutase SOD1 SOD2 SOD3
1.16: Oxidizing metal ions	Ceruloplasmin (Methionine synthase) reductase
1.17: Acting on CH or CH2 groups	Xanthine oxidase Ribonucleotide reductase 4-Hydroxy-3-methylbut-2-enyl diphosphate reductase 7-Hydroxymethyl chlorophyll a reductase
1.18: Acting on iron–sulfur proteins as donors	Nitrogenase
1.19: Acting on reduced flavodoxin as donor	Nitrogenase (flavodoxin)
1.20: Acting on phosphorus or arsenic in donors	Glutaredoxin GLRX GLRX2 GLRX3 GLRX5
1.21: Acting on X-H and Y-H to form an X-Y bond	Isopenicillin N synthase Columbamine oxidase Reticuline oxidase Sulochrin oxidase (+)-bisdechlorogeodin-forming (-)-bisdechlorogeodin-forming Aureusidin synthase Tetrahydrocannabinolic acid synthase Cannabidiolic acid synthase Dichlorochromopyrrolate synthase

v t e Enzymes
Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Diffusion-limited enzyme Cofactor Enzyme catalysis
Regulation	Allosteric regulation Cooperativity Enzyme inhibitor Enzyme activator
Classification	EC number Enzyme superfamily Enzyme family List of enzymes
Kinetics	Enzyme kinetics Eadie–Hofstee diagram Hanes–Woolf plot Lineweaver–Burk plot Michaelis–Menten kinetics
Types	EC1 Oxidoreductases (list) EC2 Transferases (list) EC3 Hydrolases (list) EC4 Lyases (list) EC5 Isomerases (list) EC6 Ligases (list) EC7 Translocases (list)