5β-Reductase

'''5β-Reductase''', or '''Δ⁴-3-oxosteroid 5β-reductase''' ({{EC number|1.3.1.3}}, ''3-oxo-Δ⁴-steroid 5β-reductase'', ''androstenedione 5β-reductase'', ''cholestenone 5β-reductase'', ''cortisone 5β-reductase'', ''cortisone Δ⁴-5β-reductase'', ''steroid 5β-reductase'', ''testosterone 5β-reductase'', ''Δ⁴-3-ketosteroid 5β-reductase'', ''Δ⁴-5β-reductase'', ''Δ⁴-hydrogenase'', ''4,5β-dihydrocortisone:NADP⁺ Δ⁴-oxidoreductase'', ''3-oxo-5β-steroid:NADP⁺ Δ⁴-oxidoreductase'') is an enzyme with systematic name ''5β-cholestan-3-one:NADP⁺ 4,5-oxidoreductase''.<ref>{{cite journal | vauthors = Dorfman RI, Forchielli E | title = Separation of delta 4-5 alpha-hydrogenases from rat liver homogenates | journal = The Journal of Biological Chemistry | volume = 223 | issue = 1 | pages = 443–8 | date = November 1956 | doi = 10.1016/S0021-9258(18)65153-1 | doi-access = free | pmid = 13376613 }}</ref><ref>{{cite journal | vauthors = Brown-Grant K, Forchielli E, Dorfman RI | title = The delta4-hydrogenases of guinea pig adrenal gland | journal = The Journal of Biological Chemistry | volume = 235 | pages = 1317–20 | date = May 1960 | issue = 5 | doi = 10.1016/S0021-9258(18)69405-0 | doi-access = free | pmid = 13805063 }}</ref><ref>{{cite journal | title = Enzymatic introduction of double bonds into steroid ring A |author = Levy, H.R. |author2 = Talalay, P. |name-list-style = amp |journal = J. Am. Chem. Soc. |year = 1957 |volume = 79 |issue = 10 |pages = 2658–2659 |doi=10.1021/ja01567a089 |bibcode = 1957JAChS..79.2658L }}</ref><ref>{{cite journal | vauthors = Tomkins GM | title = The enzymatic reduction of delta 4-3-ketosteroids | journal = The Journal of Biological Chemistry | volume = 225 | issue = 1 | pages = 13–24 | date = March 1957 | doi = 10.1016/S0021-9258(18)64906-3 | doi-access = free | pmid = 13416214 }}</ref><ref>{{cite journal | vauthors = Sugimoto Y, Yoshida M, Tamaoki B | title = Purification of 5 beta-reductase from hepatic cytosol fraction of chicken | journal = The Journal of Steroid Biochemistry and Molecular Biology | volume = 37 | issue = 5 | pages = 717–24 | date = December 1990 | pmid = 2278855 | doi = 10.1016/0960-0760(90)90356-p | s2cid = 54431282 }}</ref><ref>{{cite journal | vauthors = Okuda A, Okuda K | title = Purification and characterization of delta 4-3-ketosteroid 5 beta-reductase | journal = The Journal of Biological Chemistry | volume = 259 | issue = 12 | pages = 7519–24 | date = June 1984 | doi = 10.1016/S0021-9258(17)42821-3 | doi-access = free | pmid = 6736016 }}</ref><ref>{{cite journal | vauthors = Charbonneau A, The VL | title = Genomic organization of a human 5beta-reductase and its pseudogene and substrate selectivity of the expressed enzyme | journal = Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression | volume = 1517 | issue = 2 | pages = 228–35 | date = January 2001 | pmid = 11342103 | doi = 10.1016/s0167-4781(00)00278-5 }}</ref><ref>{{cite journal | vauthors = Kondo KH, Kai MH, Setoguchi Y, Eggertsen G, Sjöblom P, Setoguchi T, Okuda KI, Björkhem I | title = Cloning and expression of cDNA of human delta 4-3-oxosteroid 5 beta-reductase and substrate specificity of the expressed enzyme | journal = European Journal of Biochemistry | volume = 219 | issue = 1–2 | pages = 357–63 | date = January 1994 | pmid = 7508385 | doi = 10.1111/j.1432-1033.1994.tb19947.x | doi-access = free }}</ref>

{{Short description|Class of enzymes}} {{Infobox enzyme | Name = Δ⁴-3-Oxosteroid 5β-reductase | EC_number = 1.3.1.3 | CAS_number = 2604034 | GO_code = | image = | width = | caption = }}

This enzyme catalyses the following general chemical reaction:

:5β-cholestan-3-one + NADP⁺ <math>\rightleftharpoons</math> cholest-4-en-3-one + NADPH + H⁺

For example, it interconverts 5β-dihydrocortisone and cortisone:<ref name=KEGG>{{KEGG enzyme|1.3.1.3}}</ref><ref>{{cite journal | vauthors = Furuebisu M, Deguchi S, Okuda K | title = Identification of cortisone 5 beta-reductase as delta 4-3-ketosteroid 5 beta-reductase | journal = Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology | volume = 912 | issue = 1 | pages = 110–4 | date = March 1987 | pmid = 3828348 | doi = 10.1016/0167-4838(87)90253-6 }}</ref>

{{chemrxn|width=60%| {{chemrxn/cpd|dihydrocortisone }} {{chemrxn/txt| + NADP⁺ }} {{chemrxn/arw|direction=reversible|fwd_out={{chem2|H+}}|rev_in={{chem2|H+}} }} {{chemrxn/cpd|cortisone }} {{chemrxn/txt|+ NADPH}} }}

The human enzyme efficiently acts on progesterone, 17α-hydroxyprogesterone, androstenedione, and testosterone to transform them into 5β-reduced metabolites. It can also act on aldosterone, corticosterone, and cortisol.<ref name=KEGG/>

== See also == * 5α-Reductase * Steroidogenic enzyme

== References == {{Reflist}}

== External links == * {{MeshName|Delta4-3-oxosteroid+5beta-reductase}}

{{CH-CH oxidoreductases}} {{Enzymes}} {{Portal bar|Biology|border=no}}

Category:EC 1.3.1