Reaction: arsenate + glutaredoxin = arsenite + glutaredoxin disulfide + H2O
For diagram of reaction click here.
Systematic name: glutharedoxin:arsenate oxidoreductase
Comments: A molybdoenzyme. The glutaredoxins catalyse glutathione-disulfide oxidoreductions and have a redox-active disulfide/dithiol in the active site (-Cys-Pro-Tyr-Cys-) that forms a disulfide bond in the oxidized form [2, 10]. Glutaredoxins have a binding site for glutathione, which is required to reduce them to the dithiol form [3, 6]. Thioredoxins reduced by NADPH and thioredoxin reductase can act as alternative substrates. The enzyme [1, 4, 7, 9] is part of a system for detoxifying arsenate. Although the arsenite formed is more toxic than arsenate, it can be extruded from some bacteria by EC 22.214.171.124, arsenite-transporting ATPase; in other organisms, arsenite can be methylated by EC 126.96.36.199, arsenite methyltransferase, in a pathway to non-toxic organoarsenical compounds.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, UM-BBD, CAS registry number: 146907-46-2
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