ID   1.3.1.3
DE   Delta(4)-3-oxosteroid 5-beta-reductase.
AN   3-oxo-Delta(4)-steroid 5-beta-reductase.
AN   5-beta-reductase.
AN   Androstenedione 5-beta-reductase.
AN   Cholestenone 5-beta-reductase.
AN   Cortisone 5-beta-reductase.
AN   Cortisone beta-reductase.
AN   Cortisone Delta(4)-5-beta-reductase.
AN   Delta(4)-3-ketosteroid 5-beta-reductase.
AN   Delta(4)-5-beta-reductase.
AN   Delta(4)-hydrogenase.
AN   Steroid 5-beta-reductase.
AN   Testosterone 5-beta-reductase.
CA   (1) 5-beta-cholestan-3-one + NADP(+) = cholest-4-en-3-one + NADPH.
CA   (2) 17,21-dihydroxy-5-beta-pregnane-3,11,20-trione + NADP(+) = cortisone
CA   + NADPH.
CC   -!- The enzyme from human efficiently catalyzes the reduction of
CC       progesterone, androstenedione, 17-alpha-hydroxyprogesterone and
CC       testosterone to 5-beta-reduced metabolites; it can also act on
CC       aldosterone, corticosterone and cortisol, but to a lesser extent.
CC   -!- The bile acid intermediates 7-alpha,12-alpha-dihydroxy-4-cholesten-3-
CC       one and 7-alpha-hydroxy-4-cholesten-3-one can also act as substrates.
PR   PROSITE; PDOC00061;
DR   P51857, AK1D1_HUMAN;  Q8VCX1, AK1D1_MOUSE;  Q9TV64, AK1D1_RABIT;
DR   P31210, AK1D1_RAT  ;
//