CATH Classification

Domain Context

CATH Clusters

Superfamily Urate Oxidase;
Functional Family

Enzyme Information
2-oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline decarboxylase.
based on mapping to UniProt Q45697
5-hydroxy-2-oxo-4-ureido-2,5-dihydro-1H-imidazole-5-carboxylate = (S)- allantoin + CO(2).
-!- This enzyme is part of the pathway from urate to (S)-allantoin, which is present in bacteria, plants and animals (but not in humans). -!- Formerly EC 4.1.1.n1.
Factor independent urate hydroxylase.
based on mapping to UniProt Q45697
Urate + O(2) + H(2)O = 5-hydroxyisourate + H(2)O(2).
-!- Was previously thought to be a copper protein, but it is now known that the enzymes from soybean (Glycine max), the mold Aspergillus flavus and Bacillus subtilis contains no copper nor any other transition-metal ion. -!- The 5-hydroxyisourate formed decomposes spontaneously to form allantoin and CO(2), although there is an enzyme-catalyzed pathway in which EC catalyzes the first step. -!- The enzyme is different from EC

UniProtKB Entries (1)

Bacillus sp. TB-90
Uric acid degradation bifunctional protein

PDB Structure

External Links
Primary Citation
Crystal structure of urate oxidase from Bacillus SP.
Hibi, T., Nago, T., Nishiya, Y., Oda, J.
To be Published