ENZYME

ENZYME entry: EC 1.10.99.2

Accepted Name

Ribosyldihydronicotinamide dehydrogenase (quinone).

Alternative Name(s)

N-ribosyldihydronicotinamide dehydrogenase (quinone).

NAD(P)H:quinone oxidoreductase 2.

NQO(2).

NRH:quinone oxidoreductase 2.

QR2.

Quinone reductase 2.

Reaction catalysed

1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone <=> 1-(beta-D-ribofuranosyl)nicotinamide + a hydroquinone

Cofactor(s)

FAD; Zinc.

Comment(s)

Unlike EC 1.6.5.2, this quinone reductase cannot use NADH or NADPH; instead it uses N-ribosyl- and N-alkyldihydronicotinamides.
Polycyclic aromatic hydrocarbons, such as benz[a]anthracene, and the estrogens 17-beta-estradiol and diethylstilbestrol are potent inhibitors, but dicoumarol is only a very weak inhibitor.
This enzyme can catalyze both 2-electron and 4-electron reductions, but one-electron acceptors, such as potassium ferricyanide, cannot be reduced.

Cross-references

BRENDA

EC2PDB

ExplorEnz

PRIAM enzyme-specific profiles

KEGG Ligand Database for Enzyme Nomenclature

IUBMB Enzyme Nomenclature