Family

Urocanase (IPR023637)

Short name: Urocanase

Family relationships

None.

Description

Urocanase [PMID: 7944380] (also known as imidazolonepropionate hydrolase or urocanate hydratase) is the enzyme that catalyses the second step in the degradation of histidine, the hydration of urocanate into imidazolonepropionate: urocanate + H2O = 4,5-dihydro-4-oxo-5-imidazolepropanoate Urocanase is found in some bacteria (gene hutU) [PMID: 4990470], in the liver of many vertebrates, and has also been found in the plant Trifolium repens (white clover). Urocanase is a protein of about 60 Kd, it binds tightly to NAD+ and uses it as an electrophil cofactor. A conserved cysteine has been found to be important for the catalytic mechanism and could be involved in the binding of the NAD+.

This enzyme is a symmetric homodimer with tightly bound NAD+ cofactors. Each subunit consists of a typical NAD-binding domain inserted into a larger core domain that forms the dimer interface [PMID: 15313616].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0016153 urocanate hydratase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
TIGRFAMs
PIRSF
SUPERFAMILY
Pfam
PANTHER
HAMAP