Pathways & interactions
Aldehyde oxidase/xanthine dehydrogenase, molybdopterin binding domain superfamily (IPR037165)
Short name: AldOxase/xan_DH_Mopterin-bd_sf
- Aldehyde oxidase/xanthine dehydrogenase, molybdopterin binding (IPR008274)
- Carbon-monoxide dehydrogenase, large subunit (IPR012780)
- Xanthine dehydrogenase, molybdopterin binding subunit (IPR014309)
- 4-hydroxybenzoyl-CoA reductase, alpha subunit (IPR017607)
- Xanthine dehydrogenase D subunit (IPR017609)
- Selenium-dependent xanthine dehydrogenase (IPR017697)
- Molybdenum-binding protein YgfN/XdhD (IPR017699)
Aldehyde oxidase (EC:18.104.22.168) catalyses the conversion of an aldehyde in the presence of oxygen and water to an acid and hydrogen peroxide. The enzyme is a homodimer, and requires FAD, molybdenum and two 2FE-2S clusters as cofactors. Xanthine dehydrogenase (EC:22.214.171.124) catalyses the hydrogenation of xanthine to urate, and also requires FAD, molybdenum and two 2FE-2S clusters as cofactors. This activity is often found in a bifunctional enzyme with xanthine oxidase (EC:126.96.36.199) activity too. The enzyme can be converted from the dehydrogenase form to the oxidase form irreversibly by proteolysis or reversibly through oxidation of sulphydryl groups.
The aldehyde oxido-reductase (Mop) from the sulphate reducing anaerobic Gram-negative bacterium Desulfovibrio gigas is a homodimer of 907 amino acid residues subunits and is a member of the xanthine oxidase family. The protein contains a molybdopterin cofactor (Mo-co) and two different [2Fe-2S] centres. It is folded into four domains of which the first two bind the iron sulphur centres and the last two are involved in Mo-co binding. Mo-co is a molybdenum molybdopterin cytosine dinucleotide. Molybdopterin forms a tricyclic system with the pterin bicycle annealed to a pyran ring. The molybdopterin dinucleotide is deeply buried in the protein. The cis-dithiolene group of the pyran ring binds the molybdenum, which is coordinated by three more (oxygen) ligands [PMID: 7502041].
This superfamily represents the molybdopterin binding domain.
- SSF56003 (SSF56003)