InterPro domain: IPR005025

This domain in found in several flavoproteins such as FMN-dependent NADPH-azoreductase, which catalyses the reductive cleavage of azo bond in aromatic azo compounds to the corresponding amines [ 1 ], and NAD(P)H:quinone oxidoreductase, which reduces quinones to the hydroquinone state to prevent interaction of the semiquinone with O2 and production of superoxide [ 2 ]. In Arabidopsis NADPH:quinone oxidoreductase is involved in detoxification pathways [ 3 ]. NAD(P)H:quinone oxidoreductase prefers NADH over NADPH, while FMN-dependent NADPH-azoreductase requires NADPH, but not NADH, as an electron donor for its activity.

Other proteins with this domain include iron-sulfur flavoproteins [ 4 ] and chromate reductase [ 5 ].

1. Characterization of a thermostable NADPH:FMN oxidoreductase from the mesophilic bacterium Bacillus subtilis. Biochemistry 45, 7083-91
2. Biochemical characterization of WrbA, founding member of a new family of multimeric flavodoxin-like proteins. J. Biol. Chem. 273, 20960-6
3. Cloning and heterologous expression of NAD(P)H:quinone reductase of Arabidopsis thaliana, a functional homologue of animal DT-diaphorase. FEBS Lett. 463, 382-6
4. Iron-sulfur flavoprotein (Isf) from Methanosarcina thermophila is the prototype of a widely distributed family. J. Bacteriol. 183, 6225-33
5. Chromate-reducing properties of soluble flavoproteins from Pseudomonas putida and Escherichia coli. Appl. Environ. Microbiol. 70, 873-82