Nitrate reductase (NAD(P)H) (, assimilatory nitrate reductase, assimilatory NAD(P)H-nitrate reductase, NAD(P)H bispecific nitrate reductase, nitrate reductase (reduced nicotinamide adenine dinucleotide (phosphate)), nitrate reductase NAD(P)H, NAD(P)H-nitrate reductase, nitrate reductase [NAD(P)H<sub>2</sub>], NAD(P)H<sub>2</sub>:nitrate oxidoreductase) is an enzyme with systematic name nitrite:NAD(P)<sup>+</sup> oxidoreductase. This enzyme catalises the following chemical reaction
Nitrate reductase is an iron-sulfur molybdenum flavoprotein.