4-hydroxybenzoyl-CoA reductase, beta subunit (IPR017608)

Short name: 4hydrxbenzoyl-CoA_Rdtase_bsu

Overlapping homologous superfamilies

Family relationships



4-Hydroxybenzoyl-CoA reductase (4-HBCR) is a member of the xanthine oxidase (XO) family of molybdenum cofactor containing enzymes. It catalyses the irreversible removal of a phenolic hydroxy group by reduction, yielding water and benzoyl-CoA, which is a common intermediate in the anaerobic degradation of aromatic compounds.

4-HBCR has a heterodimer subunit compositon of alpha2-beta2-gamma2. 4-HBCR contains two molybdopterins, four [2Fe-2S], two [4Fe-4S] clusters and two FADs [PMID: 14747735]. A ferredoxin with two [4Fe-4S] clusters functions as the natural electron donor. The enzyme is reversibly inactivated by cyanide, titanium(III) citrate and dithionite. Dithionite and azide bind directly to equatorial ligation sites of the Mo atom [PMID: 18393440].

This entry represents the second largest chain, beta (HcrB, 35kDa), of the enzyme 4-hydroxybenzoyl-CoA reductase. In Thauera aromatica, there is an additional domain in the beta-subunit, which probably has an extra iron-sulphur cluster [PMID: 9490068].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.