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Your query returned 8 entries. Printable version
EC | 1.1.1.149 | ||||||||||||||||||
Accepted name: | 20α-hydroxysteroid dehydrogenase | ||||||||||||||||||
Reaction: | 17α,20α-dihydroxypregn-4-en-3-one + NAD(P)+ = 17α-hydroxyprogesterone + NAD(P)H + H+ | ||||||||||||||||||
Other name(s): | 20α-hydroxy steroid dehydrogenase; 20α-HSD; 20α-HSDH | ||||||||||||||||||
Systematic name: | 20α-hydroxysteroid:NAD(P)+ 20-oxidoreductase | ||||||||||||||||||
Comments: | Re-specific with respect to NAD(P)+ (cf. EC 1.1.1.62 17β-estradiol 17-dehydrogenase). | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9040-08-8 | ||||||||||||||||||
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EC | 1.3.1.3 | ||||||||||||||||||
Accepted name: | Δ4-3-oxosteroid 5β-reductase | ||||||||||||||||||
Reaction: | a 3-oxo-5β-steroid + NADP+ = a 3-oxo-Δ4-steroid + NADPH + H+ | ||||||||||||||||||
For diagram of cholesterol catabolism (rings a, B and c), click here | |||||||||||||||||||
Other name(s): | 3-oxo-Δ4-steroid 5β-reductase; 5β-reductase; androstenedione 5β-reductase; cholestenone 5β-reductase; cortisone 5β-reductase; cortisone β-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; 5β-cholestan-3-one:NADP+ 4,5-oxidoreductase | ||||||||||||||||||
Systematic name: | 3-oxo-5β-steroid:NADP+ 4,5-oxidoreductase | ||||||||||||||||||
Comments: | The enzyme from human efficiently catalyses the reduction of progesterone, androstenedione, 17α-hydroxyprogesterone and testosterone to 5β-reduced metabolites; it can also act on aldosterone, corticosterone and cortisol, but to a lesser extent [8]. The bile acid intermediates 7α,12α-dihydroxy-4-cholesten-3-one and 7α-hydroxy-4-cholesten-3-one can also act as substrates [9]. | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9029-08-7 | ||||||||||||||||||
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EC | 1.14.13.54 | ||||||||||||||||||
Accepted name: | ketosteroid monooxygenase | ||||||||||||||||||
Reaction: | a ketosteroid + NADPH + H+ + O2 = a steroid ester/lactone + NADP+ + H2O (general reaction) (1) progesterone + NADPH + H+ + O2 = testosterone acetate + NADP+ + H2O (2) androstenedione + NADPH + H+ + O2 = testololactone + NADP+ + H2O (3) 17α-hydroxyprogesterone + NADPH + H+ + O2 = androstenedione + acetate + NADP+ + H2O |
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Glossary: | progesterone = pregn-4-ene-3,20-dione testosterone acetate = 3-oxoandrost-4-en-17β-yl acetate androstenedione = androst-4-ene-3,17-dione testololactone = 3-oxo-13,17-secoandrost-4-eno-17,13α-lactone 17α-hydroxyprogesterone = 17α-hydroxypregn-4-ene-3,20-dione |
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Other name(s): | steroid-ketone monooxygenase; progesterone, NADPH2:oxygen oxidoreductase (20-hydroxylating, ester-producing); 17α-hydroxyprogesterone, NADPH2:oxygen oxidoreductase (20-hydroxylating, side-chain cleaving); androstenedione, NADPH2:oxygen oxidoreductase (17-hydroxylating, lactonizing) | ||||||||||||||||||
Systematic name: | ketosteroid,NADPH:oxygen oxidoreductase (20-hydroxylating, ester-producing/20-hydroxylating, side-chain cleaving/17-hydroxylating, lactonizing) | ||||||||||||||||||
Comments: | A single FAD-containing enzyme catalyses three types of monooxygenase (Baeyer-Villiger oxidation) reaction. The oxidative esterification of a number of derivatives of progesterone to produce the corresponding 17α-hydroxysteroid 17-acetate ester, such as testosterone acetate, is shown in Reaction (1). The oxidative lactonization of a number of derivatives of androstenedione to produce the 13,17-secoandrosteno-17,13α-lactone, such as testololactone, is shown in Reaction (2). The oxidative cleavage of the 17β-side-chain of 17α-hydroxyprogesterone to produce androstenedione and acetate is shown in Reaction (3). Reaction (1) is also catalysed by EC 1.14.99.4 (progesterone monooxygenase), and Reactions (2) and (3) correspond to that catalysed by EC 1.14.99.12 (androst-4-ene-3,17-dione monooxygenase). The possibility that a single enzyme is responsible for the reactions ascribed to EC 1.14.99.4 and EC 1.14.99.12 in other tissues cannot be excluded. | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9044-53-5 | ||||||||||||||||||
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EC | 1.14.14.16 | ||||||||||||||||||
Accepted name: | steroid 21-monooxygenase | ||||||||||||||||||
Reaction: | a C21 steroid + [reduced NADPH—hemoprotein reductase] + O2 = a 21-hydroxy-C21-steroid + [oxidized NADPH—hemoprotein reductase] + H2O | ||||||||||||||||||
Other name(s): | steroid 21-hydroxylase; 21-hydroxylase; P450c21; CYP21A2 (gene name) | ||||||||||||||||||
Systematic name: | steroid,NADPH—hemoprotein reductase:oxygen oxidoreductase (21-hydroxylating) | ||||||||||||||||||
Comments: | A P-450 heme-thiolate protein responsible for the conversion of progesterone and 17α-hydroxyprogesterone to their respective 21-hydroxylated derivatives, 11-deoxycorticosterone and 11-deoxycortisol. Involved in the biosynthesis of the hormones aldosterone and cortisol. The electron donor is EC 1.6.2.4, NADPH—hemoprotein reductase. | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9029-68-9 | ||||||||||||||||||
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EC | 1.14.14.19 | ||||||||||||||||||
Accepted name: | steroid 17α-monooxygenase | ||||||||||||||||||
Reaction: | a C21-steroid + [reduced NADPH—hemoprotein reductase] + O2 = a 17α-hydroxy-C21-steroid + [oxidized NADPH—hemoprotein reductase] + H2O |
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Other name(s): | steroid 17α-hydroxylase; cytochrome P-450 17α; cytochrome P-450 (P-450 17α,lyase); 17α-hydroxylase-C17,20 lyase; CYP17; CYP17A1 (gene name) | ||||||||||||||||||
Systematic name: | steroid,NADPH—hemoprotein reductase:oxygen oxidoreductase (17α-hydroxylating) | ||||||||||||||||||
Comments: | Requires NADPH and EC 1.6.2.4, NADPH—hemoprotein reductase. A microsomal hemeprotein that catalyses two independent reactions at the same active site - the 17α-hydroxylation of pregnenolone and progesterone, which is part of glucocorticoid hormones biosynthesis, and the conversion of the 17α-hydroxylated products via a 17,20-lyase reaction to form androstenedione and dehydroepiandrosterone, leading to sex hormone biosynthesis (EC 1.14.14.32, 17α-hydroxyprogesterone deacetylase). The ratio of the 17α-hydroxylase and 17,20-lyase activities is an important factor in determining the directions of steroid hormone biosynthesis towards biosynthesis of glucocorticoid or sex hormones. | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9029-67-8 | ||||||||||||||||||
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EC | 1.14.14.32 | ||||||||||||||||||
Accepted name: | 17α-hydroxyprogesterone deacetylase | ||||||||||||||||||
Reaction: | (1) 17α-hydroxyprogesterone + [reduced NADPH—hemoprotein reductase] + O2 = androstenedione + acetate + [oxidized NADPH—hemoprotein reductase] + H2O (2) 17α-hydroxypregnenolone + [reduced NADPH—hemoprotein reductase] + O2 = 3β-hydroxyandrost-5-en-17-one + acetate + [oxidized NADPH—hemoprotein reductase] + H2O |
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Glossary: | androstenedione = androst-4-ene-3,17-dione | ||||||||||||||||||
Other name(s): | C-17/C-20 lyase; 17α-hydroxyprogesterone acetaldehyde-lyase; CYP17; CYP17A1 (gene name); 17α-hydroxyprogesterone 17,20-lyase | ||||||||||||||||||
Systematic name: | 17α-hydroxyprogesterone,NADPH—hemoprotein reductase:oxygen oxidoreductase (17α-hydroxylating, acetate-releasing) | ||||||||||||||||||
Comments: | A microsomal cytochrome P-450 (heme-thiolate) protein that catalyses two independent reactions at the same active site - the 17-hydroxylation of pregnenolone and progesterone, which is part of glucocorticoid hormones biosynthesis (EC 1.14.14.19), and the conversion of the 17-hydroxylated products via a 17,20-lyase reaction to form androstenedione and 3β-hydroxyandrost-5-en-17-one, leading to sex hormone biosynthesis. The activity of this reaction is dependent on the allosteric interaction of the enzyme with cytochrome b5 without any transfer of electrons from the cytochrome [2,4]. The enzymes from different organisms differ in their substrate specificity. While the enzymes from pig, hamster, and rat accept both 17α-hydroxyprogesterone and 17α-hydroxypregnenolone, the enzymes from human, bovine, sheep, goat, and bison do not accept the former, and the enzyme from guinea pig does not accept the latter [1]. | ||||||||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 62213-24-5 | ||||||||||||||||||
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EC | 1.14.99.10 | ||||||||||||||||||
Transferred entry: | steroid 21-monooxygenase. Now EC 1.14.14.16, steroid 21-monooxygenase | ||||||||||||||||||
EC | 4.1.2.30 | ||||||||||||||||||
Transferred entry: | 17α-hydroxyprogesterone aldolase. Now EC 1.14.14.32, 17α-hydroxyprogesterone deacetylase | ||||||||||||||||||