CATH Classification

Domain Context

CATH Clusters

Superfamily NADP-dependent oxidoreductase domain
Functional Family Aldo-keto reductase family 1 member C3

Enzyme Information

1.3.1.3
Delta(4)-3-oxosteroid 5-beta-reductase.
based on mapping to UniProt P51857
(1) 5-beta-cholestan-3-one + NADP(+) = cholest-4-en-3-one + NADPH. (2) 17,21-dihydroxy-5-beta-pregnane-3,11,20-trione + NADP(+) = cortisone + NADPH.
-!- The enzyme from human efficiently catalyzes the reduction of progesterone, androstenedione, 17-alpha-hydroxyprogesterone and testosterone to 5-beta-reduced metabolites; it can also act on aldosterone, corticosterone and cortisol, but to a lesser extent. -!- The bile acid intermediates 7-alpha,12-alpha-dihydroxy-4-cholesten-3- one and 7-alpha-hydroxy-4-cholesten-3-one can also act as substrates.

UniProtKB Entries (1)

P51857
AK1D1_HUMAN
Homo sapiens
3-oxo-5-beta-steroid 4-dehydrogenase

PDB Structure

PDB 3COT
External Links
Method X-RAY DIFFRACTION
Organism Escherichia
Primary Citation
Crystal Structure of Human Liver {Delta}4-3-Ketosteroid 5{beta}-Reductase (AKR1D1) and Implications for Substrate Binding and Catalysis.
Di Costanzo, L., Drury, J.E., Penning, T.M., Christianson, D.W.
J.Biol.Chem.