5-beta-reductase

Delta4-3-oxosteroid 5beta-reductase
Identifiers
EC number	1.3.1.3
CAS number	2604034
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Search PMC articles PubMed articles NCBI proteins

Delta4-3-oxosteroid 5beta-reductase (EC 1.3.1.3, 3-oxo-Delta4-steroid 5beta-reductase, 5beta-reductase, androstenedione 5beta-reductase, cholestenone 5beta-reductase, cortisone 5beta-reductase, cortisone beta-reductase, cortisone Delta4-5beta-reductase, steroid 5beta-reductase, testosterone 5beta-reductase, Delta4-3-ketosteroid 5beta-reductase, Delta4-5beta-reductase, Delta4-hydrogenase, 4,5beta-dihydrocortisone:NADP⁺ Delta4-oxidoreductase, 3-oxo-5beta-steroid:NADP⁺ Delta4-oxidoreductase) is an enzyme with systematic name 5beta-cholestan-3-one:NADP⁺ 4,5-oxidoreductase.^{[1][2][3][4][5][6][7][8][9]} This enzyme catalyses the following chemical reaction

(1) 5beta-cholestan-3-one + NADP⁺ $\rightleftharpoons$ cholest-4-en-3-one + NADPH + H⁺

(2) 17,21-dihydroxy-5beta-pregnane-3,11,20-trione + NADP⁺ $\rightleftharpoons$ cortisone + NADPH + H⁺

The human enzyme efficiently acts on progesterone, androstenedione, 17alpha-hydroxyprogesterone and testosterone to 5beta-reduced metabolites. It can also act on aldosterone, corticosterone and cortisol, to some extent.

References

1. Forchielli, E. and Dorfman, R.I. (1956). "Separation of Δ⁴-5α- and Δ⁴-5β-hydrogenases from rat liver homogenates". J. Biol. Chem. 223: 443–448. PMID 13376613.
2. Brown-Grant, K., Forchielli, E. and Dorfman, R.I. (1960). "The Δ⁴-hydrogenases of guinea pig adrenal gland". J. Biol. Chem. 235: 1317–1320. PMID 13805063.
3. Levy, H.R. and Talalay, P. (1957). "Enzymatic introduction of double bonds into steroid ring A". J. Am. Chem. Soc. 79: 2658–2659. doi:10.1021/ja01567a089.
4. Tomkins, G.M. (1957). "The enzymatic reduction of Δ⁴-3-ketosteroids". J. Biol. Chem. 225: 13–24. PMID 13416214.
5. Sugimoto, Y., Yoshida, M. and Tamaoki, B. (1990). "Purification of 5β-reductase from hepatic cytosol fraction of chicken". J. Steroid Biochem. 37: 717–724. doi:10.1016/0960-0760(90)90356-p. PMID 2278855.
6. Furuebisu, M., Deguchi, S. and Okuda, K. (1987). "Identification of cortisone 5β-reductase as Δ⁴-3-ketosteroid 5β-reductase". Biochim. Biophys. Acta 912: 110–114. doi:10.1016/0167-4838(87)90253-6. PMID 3828348.
7. Okuda, A. and Okuda, K. (1984). "Purification and characterization of Δ⁴-3-ketosteroid 5β-reductase". J. Biol. Chem. 259: 7519–7524. PMID 6736016.
8. Charbonneau, A. and The, V.L. (2001). "Genomic organization of a human 5β-reductase and its pseudogene and substrate selectivity of the expressed enzyme". Biochim. Biophys. Acta 1517: 228–235. doi:10.1016/s0167-4781(00)00278-5. PMID 11342103.
9. Kondo, K.H., Kai, M.H., Setoguchi, Y., Eggertsen, G., Sjöblom, P., Setoguchi, T., Okuda, K.I. and Björkhem, I. (1994). "Cloning and expression of cDNA of human Δ⁴-3-oxosteroid 5β-reductase and substrate specificity of the expressed enzyme". Eur. J. Biochem. 219: 357–363. doi:10.1111/j.1432-1033.1994.tb19947.x. PMID 7508385.

External links

• Delta4-3-oxosteroid 5beta-reductase at the US National Library of Medicine Medical Subject Headings (MeSH)