|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Small-Molecule Reactions|
EC Number: 126.96.36.1997
Enzymes and Genes:
|Clostridium scindens VPI 12708 :||3α-hydroxysteroid dehydrogenase 1
3α-hydroxysteroid dehydrogenase 2 : baiA2
3α-hydroxysteroid dehydrogenase 3 : baiA3
|Homo sapiens :||3α hydroxysteroid dehydrogenase III
retinol dehydrogenase 9 : DHRS9
In Pathway: cholate degradation (bacteria, anaerobic)
Note that this reaction equation differs from the official Enzyme Commission reaction equation for this EC number, which can be found here .
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
Enzyme Commission Primary Name: 3α-hydroxysteroid 3-dehydrogenase
Enzyme Commission Synonyms: 3α-hydroxysteroid dehydrogenase, AKR1C4 (gene name), AKR1C2 (gene name), hsdA (gene name)
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): -10.649414 [Latendresse13]
Enzyme Commission Summary:
The enzyme acts on multiple 3α-hydroxysteroids, such as androsterone and 5 α-dihydrotestosterone. The mammalian enzymes are involved in inactivation of steroid hormones, while the bacterial enzymes are involved in steroid degradation. This entry stands for enzymes whose stereo-specificity with respect to NAD+ or NADP+ is not known. [cf. EC 188.8.131.52, 3α-hydroxysteroid 3-dehydrogenase (Si-specific) and EC 184.108.40.206, 3α-hydroxysteroid 3-dehydrogenase (Re-specific)].
Instance reactions of [testosterone + NAD(P)+ → androst-4-ene-3,17-dione + NAD(P)H + H+] (220.127.116.11):
i3: testosterone + NAD+ = androst-4-ene-3,17-dione + NADH + H+ (18.104.22.168)
i4: testosterone + NADP+ ← androst-4-ene-3,17-dione + NADPH + H+ (22.214.171.124)
Instance reactions of [allopregnanolone + NAD(P)+ ↔ 5-α-pregnane-3,20-dione + NAD(P)H + H+] (126.96.36.199):
i1: allopregnanolone + NAD+ → 5-α-pregnane-3,20-dione + NADH + H+ (1.1.-.-)
i2: allopregnanolone + NADP+ ← 5-α-pregnane-3,20-dione + NADPH + H+ (188.8.131.528)
Deyashiki94: Deyashiki Y, Ogasawara A, Nakayama T, Nakanishi M, Miyabe Y, Sato K, Hara A (1994). "Molecular cloning of two human liver 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase isoenzymes that are identical with chlordecone reductase and bile-acid binder." Biochem J 299 ( Pt 2);545-52. PMID: 8172617
Khanna95: Khanna M, Qin KN, Wang RW, Cheng KC (1995). "Substrate specificity, gene structure, and tissue-specific distribution of multiple human 3 alpha-hydroxysteroid dehydrogenases." J Biol Chem 270(34);20162-8. PMID: 7650035
Mobus98: Mobus E, Maser E (1998). "Molecular cloning, overexpression, and characterization of steroid-inducible 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase from Comamonas testosteroni. A novel member of the short-chain dehydrogenase/reductase superfamily." J Biol Chem 273(47);30888-96. PMID: 9812981
Nahoum01: Nahoum V, Gangloff A, Legrand P, Zhu DW, Cantin L, Zhorov BS, Luu-The V, Labrie F, Breton R, Lin SX (2001). "Structure of the human 3alpha-hydroxysteroid dehydrogenase type 3 in complex with testosterone and NADP at 1.25-A resolution." J Biol Chem 276(45);42091-8. PMID: 11514561
Oppermann96: Oppermann UC, Maser E (1996). "Characterization of a 3 alpha-hydroxysteroid dehydrogenase/carbonyl reductase from the gram-negative bacterium Comamonas testosteroni." Eur J Biochem 241(3);744-9. PMID: 8944761
©2015 SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025-3493