IUBMB Enzyme Nomenclature


Accepted name: NAD(P)H dehydrogenase (quinone)

Reaction: NAD(P)H + H+ + a quinone = NAD(P)+ + a hydroquinone

For diagram of reaction click here.

Other name(s): menadione reductase; phylloquinone reductase; quinone reductase; dehydrogenase, reduced nicotinamide adenine dinucleotide (phosphate, quinone); DT-diaphorase; flavoprotein NAD(P)H-quinone reductase; menadione oxidoreductase; NAD(P)H dehydrogenase; NAD(P)H menadione reductase; NAD(P)H-quinone dehydrogenase; NAD(P)H-quinone oxidoreductase; NAD(P)H: (quinone-acceptor)oxidoreductase; NAD(P)H: menadione oxidoreductase; NADH-menadione reductase; naphthoquinone reductase; p-benzoquinone reductase; reduced NAD(P)H dehydrogenase; viologen accepting pyridine nucleotide oxidoreductase; vitamin K reductase; diaphorase; reduced nicotinamide-adenine dinucleotide (phosphate) dehydrogenase; vitamin-K reductase; NAD(P)H2 dehydrogenase (quinone); NQO1; QR1; NAD(P)H:(quinone-acceptor) oxidoreductase

Systematic name: NAD(P)H:quinone oxidoreductase

Comments: A flavoprotein. The enzyme catalyses a two-electron reduction and has a preference for short-chain acceptor quinones, such as ubiquinone, benzoquinone, juglone and duroquinone [6]. The animal, but not the plant, form of the enzyme is inhibited by dicoumarol.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9032-20-6


1. di Prisco, G., Casola, L. and Giuditta, A. Purification and properties of a soluble reduced nicotinamide-adenine dinucleotide (phosphate) dehydrogenase from the hepatopancreas of Octopus vulgaris. Biochem. J. 105 (1967) 455-460. [PMID: 4171422]

2. Giuditta, A. and Strecker, H.J. Purification and some properties of a brain diaphorase. Biochim. Biophys. Acta 48 (1961) 10-19. [PMID: 13705804]

3. Märki, F. and Martius, C. Vitamin K-Reductase, Darsellung und Eigenschaften. Biochem. Z. 333 (1960) 111-135. [PMID: 13765127]

4. Misaka, E. and Nakanishi, K. Studies on menadione reductase of bakers' yeast. I. Purification, crystallization and some properties. J. Biochem. (Tokyo) 53 (1963) 465-471.

5. Wosilait, W.D. The reduction of vitamin K1 by an enzyme from dog liver. J. Biol. Chem. 235 (1960) 1196-1201. [PMID: 13846011]

6. Sparla, F., Tedeschi, G. and Trost, P. NAD(P)H:(quinone-acceptor) oxidoreductase of tobacco leaves is a flavin mononucleotide-containing flavoenzyme. Plant Physiol. 112 (1996) 249-258. [PMID: 12226388]

7. Braun, M., Bungert, S. and Friedrich, T. Characterization of the overproduced NADH dehydrogenase fragment of the NADH:ubiquinone oxidoreductase (complex I) from Escherichia coli. Biochemistry 37 (1998) 1861-1867. [PMID: 9485311]

8. Jaiswal, A.K. Characterization and partial purification of microsomal NAD(P)H:quinone oxidoreductases. Arch. Biochem. Biophys. 375 (2000) 62-68. [PMID: 10683249]

9. Li, R., Bianchet, M.A., Talalay, P. and Amzel, L.M. The three-dimensional structure of NAD(P)H:quinone reductase, a flavoprotein involved in cancer chemoprotection and chemotherapy: mechanism of the two-electron reduction. Proc. Natl. Acad. Sci. USA 92 (1995) 8846-8850. [PMID: 7568029]

[EC created 1961, transferred 1965 to EC, transferred 2005 to EC]

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