3beta-hydroxy-5beta-steroid dehydrogenase explained

3beta-hydroxy-5beta-steroid dehydrogenase
Ec Number:	1.1.1.277

In enzymology, a 3beta-hydroxy-5beta-steroid dehydrogenase is an enzyme that catalyzes the chemical reaction

3beta-hydroxy-5beta-pregnane-20-one + NADP⁺

\rightleftharpoons 5beta-pregnan-3,20-dione + NADPH + H⁺

Thus, the two substrates of this enzyme are 3beta-hydroxy-5beta-pregnane-20-one and NADP⁺, whereas its 3 products are 5beta-pregnan-3,20-dione, NADPH, 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 3beta-hydroxy-5beta-steroid:NADP⁺ 3-oxidoreductase. Other names in common use include 3beta-hydroxysteroid 5beta-oxidoreductase, and 3beta-hydroxysteroid 5beta-progesterone oxidoreductase.

References

• Stuhlemmer U, Kreis W . 1996 . Cardenolide formation and activity of pregnane-modifying enzymes in cell suspension cultures, shoot cultures and leaves of Digitalis lanata . Plant Physiol. Biochem. . 34 . 85 - 91 .
• Seitz HU, Gaertner DE . 1994 . Enzymes in cardenolide-accumulating shoot cultures of Digitalis purpurea . Plant Cell . 38 . 337 - 344 . 10.1007/bf00033894.
• Lindemann P, Luckner M . 1997 . Biosynthesis of pregnane derivatives in somatic embryos of Digitalis lanata . . 46 . 507 - 513 . 10.1016/S0031-9422(97)00315-4 . 3 .