KEGG   ENZYME: 1.14.99.9Help
Entry
EC 1.14.99.9                Enzyme                                 

Name
steroid 17alpha-monooxygenase;
steroid 17alpha-hydroxylase;
cytochrome P-45017alpha;
cytochrome P-450 (P-45017alpha,lyase);
17alpha-hydroxylase-C17,20 lyase;
CYP17;
CYP17A1 (gene name)
Class
Oxidoreductases;
Acting on paired donors, with incorporation or reduction of molecular oxygen;
Miscellaneous
BRITE hierarchy
Sysname
steroid,NADPH---hemoprotein reductase:oxygen oxidoreductase (17alpha-hydroxylating)
Reaction(IUBMB)
a C21-steroid + [reduced NADPH---hemoprotein reductase] + O2 = a 17alpha-hydroxy-C21-steroid + [oxidized NADPH---hemoprotein reductase] + H2O [RN:R02131]
Reaction(KEGG)
Substrate
C21-steroid;
[reduced NADPH---hemoprotein reductase];
O2 [CPD:C00007]
Product
17alpha-hydroxy-C21-steroid;
[oxidized NADPH---hemoprotein reductase];
H2O [CPD:C00001]
Comment
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 17alpha-hydroxylation of pregnenolone and progesterone, which is part of glucocorticoid hormones biosynthesis, and the conversion of the 17alpha-hydroxylated products via a 17,20-lyase reaction to form androstenedione and dehydroepiandrosterone, leading to sex hormone biosynthesis (EC 4.1.2.30, 7alpha-hydroxyprogesterone aldolase). The ratio of the 17alpha-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.
History
EC 1.14.99.9 created 1961 as EC 1.99.1.9, transferred 1965 to EC 1.14.1.7, transferred 1972 to EC 1.14.99.9, modified 2013
Pathway
Steroid hormone biosynthesis
Metabolic pathways
Orthology
K00512  
steroid 17alpha-monooxygenase / 17alpha-hydroxyprogesterone aldolase
Genes
HSA: 
1586(CYP17A1)
PTR: 
450141(CYP17A1)
PPS: 
GGO: 
PON: 
NLE: 
MCC: 
678693(CYP17A1)
MCF: 
CJC: 
100400572(CYP17A1)
MMU: 
13074(Cyp17a1)
RNO: 
25146(Cyp17a1)
CGE: 
NGI: 
HGL: 
OCU: 
TUP: 
CFA: 
477807(CYP17A1)
AML: 
UMR: 
FCA: 
493967(CYP17A1)
PTG: 
BTA: 
BOM: 
PHD: 
CHX: 
OAS: 
101105226 493968(CYP17A1)
SSC: 
403330(CYP17A1)
CFR: 
BACU: 
LVE: 
ECB: 
100034232(CYP17A1)
MYB: 
MYD: 
PALE: 
MDO: 
SHR: 
OAA: 
GGA: 
425056(CYP17A1)
MGP: 
APLA: 
FAB: 
PHI: 
FPG: 
FCH: 
CLV: 
ASN: 
AMJ: 
102567971(CYP17A1)
PSS: 
CMY: 
ACS: 
PBI: 
XLA: 
100036774(cyp17a1)
XTR: 
100145650(cyp17a1)
DRE: 
399692(cyp17a1)
TRU: 
100125766(cyp17a2) 100125798(cyp17a1)
MZE: 
OLA: 
100125816(cyp17) 101170547(cyp17a2)
XMA: 
LCM: 
CMK: 
BFO: 
LGI: 
CIT: 
CIC: 
PVU: 
FVE: 
PXB: 
CSV: 
SOT: 
 » show all
Taxonomy
Reference
1  [PMID:13549484]
  Authors
LYNN WS Jr, BROWN RH.
  Title
The conversion of progesterone to androgens by testes.
  Journal
J. Biol. Chem. 232 (1958) 1015-30.
Reference
2  [PMID:6966286]
  Authors
Yoshida KI, Oshima H, Troen P.
  Title
Studies of the human testis. XIII. Properties of nicotinamide adenine dinucleotide (reduced form)-linked 17 alpha-hydroxylation.
  Journal
J. Clin. Endocrinol. Metab. 50 (1980) 895-9.
Reference
3  [PMID:12693981]
  Authors
Gilep AA, Estabrook RW, Usanov SA
  Title
Molecular cloning and heterologous expression in E. coli of cytochrome P45017alpha. Comparison of structural and functional properties of substrate-specific cytochromes P450 from different species.
  Journal
Biochemistry. (Mosc). 68 (2003) 86-98.
  Sequence
Reference
4  [PMID:17386955]
  Authors
Kolar NW, Swart AC, Mason JI, Swart P
  Title
Functional expression and characterisation of human cytochrome P45017alpha in Pichia pastoris.
  Journal
J. Biotechnol. 129 (2007) 635-44.
Reference
5  [PMID:18707589]
  Authors
Pechurskaya TA, Lukashevich OP, Gilep AA, Usanov SA
  Title
Engineering, expression, and purification of "soluble" human cytochrome P45017alpha and its functional characterization.
  Journal
Biochemistry. (Mosc). 73 (2008) 806-11.
Other DBs
ExplorEnz - The Enzyme Database: 
IUBMB Enzyme Nomenclature: 
ExPASy - ENZYME nomenclature database: 
BRENDA, the Enzyme Database: 
CAS: 
9029-67-8

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