Reaction: urate + NADH + H+ + O2 = 5-hydroxyisourate + NAD+ + H2O
Other name(s): HpxO enzyme; FAD-dependent urate oxidase; urate hydroxylase
Systematic name: urate,NADH:oxygen oxidoreductase (5-hydroxyisourate forming)
Comments: A flavoprotein. The reaction is part of the purine catabolic pathway in the bacterium Klebsiella pneumoniae. The enzyme is different from EC 18.104.22.168, factor-independent urate hydroxylase, found in most plants, which produces hydrogen peroxide. The product of the enzyme is a substrate for EC 22.214.171.124, hydroxyisourate hydrolase.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
1. O'Leary, S.E., Hicks, K.A., Ealick, S.E. and Begley, T.P. Biochemical characterization of the HpxO enzyme from Klebsiella pneumoniae, a novel FAD-dependent urate oxidase. Biochemistry 48 (2009) 3033-3035. [PMID: 19260710]