Reaction catalyzed by 3alpha(or 20beta)-hydroxysteroid dehydrogenase (1.1.1.53)
+
NADPH
+
=
+
NADP+
17alpha-hydroxyprogesterone
+
NADPH
+
H+
=
17alpha,20beta-dihydroxy-pregn-4-ene-3-one
+
NADP+
