KEGG   ENZYME: 1.14.14.139Help
Entry
EC 1.14.14.139              Enzyme                                 

Name
5beta-cholestane-3alpha,7alpha-diol 12alpha-hydroxylase;
5beta-cholestane-3alpha,7alpha-diol 12alpha-monooxygenase;
sterol 12alpha-hydroxylase (ambiguous);
CYP8B1;
cytochrome P450 8B1
Class
Oxidoreductases;
Acting on paired donors, with incorporation or reduction of molecular oxygen;
With reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen into the other donor
BRITE hierarchy
Sysname
5beta-cholestane-3alpha,7alpha-diol,[reduced NADPH---hemoprotein reductase]:oxygen oxidoreductase (12alpha-hydroxylating)
Reaction(IUBMB)
5beta-cholestane-3alpha,7alpha-diol + [reduced NADPH---hemoprotein reductase] + O2 = 5beta-cholestane-3alpha,7alpha,12alpha-triol + [oxidized NADPH---hemoprotein reductase] + H2O [RN:R07204]
Reaction(KEGG)
Substrate
5beta-cholestane-3alpha,7alpha-diol [CPD:C05452];
[reduced NADPH---hemoprotein reductase] [CPD:C03024];
O2 [CPD:C00007]
Product
5beta-cholestane-3alpha,7alpha,12alpha-triol [CPD:C05454];
[oxidized NADPH---hemoprotein reductase] [CPD:C03161];
H2O [CPD:C00001]
Comment
A cytochrome P-450 (heme-thiolate) protein found in mammals. This is the key enzyme in the biosynthesis of the bile acid cholic acid (3alpha,7alpha,12alpha-trihydroxy-5beta-cholanoic acid). The activity of this enzyme determines the biosynthetic ratio between cholic acid and chenodeoxycholic acid [3]. The enzyme can also hydroxylate the substrate at the 25 and 26 position, but to a lesser extent [1].
History
EC 1.14.14.139 created 2005 as EC 1.14.13.96, transferred 2018 to EC 1.14.14.139
Pathway
ec00120  Primary bile acid biosynthesis
ec01100  Metabolic pathways
Orthology
K07431  sterol 12-alpha-hydroxylase
Genes
HSA: 1582(CYP8B1)
PTR: 736962(CYP8B1)
PPS: 100969929
GGO: 101147556
PON: 100433242
NLE: 100605497
MCC: 717247
MCF: 102132602
CSAB: 103227471(CYP8B1)
RRO: 104670956
RBB: 108532333
CJC: 100402181(CYP8B1)
SBQ: 101037790
MMU: 13124(Cyp8b1)
MCAL: 110302470
MPAH: 110327161
RNO: 81924(Cyp8b1)
MUN: 110554660
CGE: 100770995
NGI: 103747146
CCAN: 109691739
OCU: 100009301(CYP8B1)
TUP: 102479742
CFA: 485619
VVP: 112921604
AML: 100464768
UMR: 103682072
UAH: 113253657
ORO: 101374077
FCA: 101082004
PTG: 102956513
AJU: 106966675
BTA: 538964(CYP8B1)
BOM: 102278686
BIU: 109576421
BBUB: 102407955
PHD: 102335997
CHX: 102173339
OAS: 101119853
SSC: 403328(CYP8B1)
CFR: 102524173
CDK: 105084606
BACU: 103000983
LVE: 103085360
OOR: 101285967
DLE: 111164311
ECB: 100054970
EPZ: 103559259
EAI: 106843165
MYB: 102245777
MYD: 102765424
MNA: 107524319
HAI: 109377081
RSS: 109445294
DRO: 112309563
PALE: 102877747
LAV: 100665029
TMU: 101356001
MDO: 100026549(CYP8B)
PCW: 110217059
OAA: 103166427
GGA: 425055(CYP8B1)
MGP: 100546803
CJO: 107308837
APLA: 101797490
ACYG: 106036789
TGU: 100217899
LSR: 110474519
SCAN: 103812684
GFR: 102041987
FAB: 101809893
PHI: 102112501
PMAJ: 107201006
CCAE: 111925558
CCW: 104686389
ETL: 114064499
FPG: 101924073
FCH: 102052323
CLV: 102083443
EGZ: 104124585
NNI: 104021734
ACUN: 113476903
ASN: 102374897
AMJ: 102573091(CYP8B1)
PSS: 102444673
CMY: 102934823
CPIC: 101950173
XLA: 108718630 108718631(cyp8b1.L) 379482(cyp8b1.S)
XTR: 100488015 100488168(cyp8b1)
NPR: 108788787
DRE: 445281(cyp8b1)
AMEX: 103039627
OLA: 101157008
XMA: 102227191
XCO: 114147167
PRET: 103479711
NFU: 107383849
CSEM: 103396384
SDU: 111231161
HCQ: 109521313
SALP: 111956862
CMK: 103188298
PCAN: 112572139
 » show all
Taxonomy
Reference
1  [PMID:6811268]
  Authors
Hansson R, Wikvall K.
  Title
Hydroxylations in biosynthesis of bile acids. Cytochrome P-450 LM4 and 12alpha-hydroxylation of 5beta-cholestane-3alpha, 7alpha-diol.
  Journal
Eur J Biochem 125:423-9 (1982)
DOI:10.1111/j.1432-1033.1982.tb06700.x
Reference
2  [PMID:6766451]
  Authors
Hansson R, Wikvall K.
  Title
Hydroxylations in biosynthesis and metabolism of bile acids. Catalytic properties of different forms of cytochrome P-450.
  Journal
J Biol Chem 255:1643-9 (1980)
Reference
3  [PMID:14643796]
  Authors
Lundell K, Wikvall K.
  Title
Gene structure of pig sterol 12alpha-hydroxylase (CYP8B1) and expression in fetal liver: comparison with expression of taurochenodeoxycholic acid 6alpha-hydroxylase (CYP4A21).
  Journal
Biochim Biophys Acta 1634:86-96 (2003)
DOI:10.1016/j.bbalip.2003.09.002
  Sequence
[ssc:403328]
Reference
4  [PMID:10747975]
  Authors
del Castillo-Olivares A, Gil G.
  Title
Alpha 1-fetoprotein transcription factor is required for the expression of sterol 12alpha -hydroxylase, the specific enzyme for cholic acid synthesis. Potential role in the bile acid-mediated regulation of gene transcription.
  Journal
J Biol Chem 275:17793-9 (2000)
DOI:10.1074/jbc.M000996200
Reference
5  [PMID:12069850]
  Authors
Yang Y, Zhang M, Eggertsen G, Chiang JY.
  Title
On the mechanism of bile acid inhibition of rat sterol 12alpha-hydroxylase gene (CYP8B1) transcription: roles of alpha-fetoprotein transcription factor and hepatocyte nuclear factor 4alpha.
  Journal
Biochim Biophys Acta 1583:63-73 (2002)
DOI:10.1016/S1388-1981(02)00186-5
Reference
6  [PMID:12543708]
  Authors
Russell DW.
  Title
The enzymes, regulation, and genetics of bile acid synthesis.
  Journal
Annu Rev Biochem 72:137-74 (2003)
DOI:10.1146/annurev.biochem.72.121801.161712
  Sequence
[hsa:1582] [mmu:13124]
Other DBs
ExplorEnz - The Enzyme Database: 1.14.14.139
IUBMB Enzyme Nomenclature: 1.14.14.139
ExPASy - ENZYME nomenclature database: 1.14.14.139
BRENDA, the Enzyme Database: 1.14.14.139

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