In enzymology, a 3-oxo-5beta-steroid 4-dehydrogenase (EC 1.3.99.6) is an enzyme that catalyzes the chemical reaction: a 3-oxo-5beta-steroid + acceptor ↔ a 3-oxo-Delta4-steroid + reduced acceptor. Thus, the two substrates of this enzyme are 3-oxo-5beta-steroid and acceptor, whereas its two products are 3-oxo-Delta4-steroid and reduced acceptor. This enzyme belongs to the family of oxidoreductases, to be specific, those acting on the CH-CH group of donor with other acceptors.http://www.creative-enzymes.com/product/3oxo5betasteroid-4dehydrogenase-From-Human-Recombinant_3380.html