3alpha(17beta) hydroxysteroid dehydrogenase (NAD )

In enzymology, a 3alpha(17beta)-hydroxysteroid dehydrogenase (NAD⁺) (EC 1.1.1.239) is an enzyme that catalyzes the chemical reaction

Thus, the two substrates of this enzyme are testosterone and NAD⁺, whereas its 3 products are androst-4-ene-3,17-dione, NADH, and H⁺.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD⁺ or NADP⁺ as acceptor. The systematic name of this enzyme class is 3alpha(or 17beta)-hydroxysteroid:NAD⁺ oxidoreductase. Other names in common use include 3alpha,17beta-hydroxy steroid dehydrogenase, 3alpha(17beta)-HSD, and 3alpha(17beta)-hydroxysteroid dehydrogenase (NAD⁺). This enzyme participates in androgen and estrogen metabolism.