In enzymology, a glycerate dehydrogenase (EC1.1.1.29) is an enzyme that catalyzes the chemical reaction

Thus, the two substrates of this enzyme are (R)-glycerate and NAD, whereas its 3 products are hydroxypyruvate, NADH, and H. However, in nature these enzymes have the ability to catalyze the reverse reaction as well. That is, hydroxypyruvate, NADH, and H can act as the substrates while (R)-glycerate and NAD are formed as products. Additionally, NADPH can take the place of NADH in this reaction.