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3alpha(or 20beta)-hydroxysteroid dehydrogenase

In enzymology, a 3alpha(or 20beta)-hydroxysteroid dehydrogenase () is an enzyme that catalyzes the chemical reaction

The two substrates of this enzyme are 3α-androstanediol and oxidised nicotinamide adenine dinucleotide (NAD<sup>+</sup>). Its products are dihydrotestosterone, reduced NADH, and a proton.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD<sup>+</sup> or NADP<sup>+</sup> as acceptor. The systematic name of this enzyme class is 3alpha(or 20beta)-hydroxysteroid:NAD<sup>+</sup> oxidoreductase. Other names in common use include cortisone reductase, (R)-20-hydroxysteroid dehydrogenase, dehydrogenase, 20beta-hydroxy steroid, Delta4-3-ketosteroid hydrogenase, 20beta-hydroxysteroid dehydrogenase, 3alpha,20beta-hydroxysteroid:NAD<sup>+</sup>-oxidoreductase, NADH-20beta-hydroxysteroid dehydrogenase, and 20beta-HSD. This enzyme participates in bile acid biosynthesis and c21-steroid hormone metabolism.

Structural studies

As of late 2007, 6 structures have been solved for this class of enzymes, with PDB accession codes , , , , , and .

References