Hydrogen dehydrogenase

In enzymology, a hydrogen dehydrogenase (EC 1.12.1.2) is an enzyme that catalyzes the chemical reaction

Thus, the two substrates of this enzyme are H₂ and NAD⁺, whereas its two products are H⁺ and NADH.

This enzyme belongs to the family of oxidoreductases, specifically those acting on hydrogen as donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is hydrogen:NAD+ oxidoreductase. Other names in common use include H2:NAD+ oxidoreductase, NAD+-linked hydrogenase, bidirectional hydrogenase, and hydrogenase. This enzyme participates in glyoxylate and dicarboxylate metabolism and methane metabolism. It has 6 cofactors: FAD, Iron, FMN, Flavin, Nickel, and Iron-sulfur.