KEGG   ENZYME: 1.14.99.38Help
Entry
EC 1.14.99.38               Enzyme                                 
Name
cholesterol 25-hydroxylase;
cholesterol 25-monooxygenase
Class
Oxidoreductases;
Acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2;
Miscellaneous
BRITE hierarchy
Sysname
cholesterol,hydrogen-donor:oxygen oxidoreductase (25-hydroxylating)
Reaction(IUBMB)
cholesterol + AH2 + O2 = 25-hydroxycholesterol + A + H2O [RN:R07218]
Reaction(KEGG)
Substrate
cholesterol [CPD:C00187];
AH2 [CPD:C00030];
O2 [CPD:C00007]
Product
25-hydroxycholesterol [CPD:C15519];
A [CPD:C00028];
H2O [CPD:C00001]
Comment
Unlike most other sterol hydroxylases, this enzyme is not a cytochrome P-450. Instead, it uses diiron cofactors to catalyse the hydroxylation of hydrophobic substrates [1]. The diiron cofactor can be either Fe-O-Fe or Fe-OH-Fe and is bound to the enzyme through interactions with clustered histidine or glutamate residues [4,5]. In cell cultures, this enzyme down-regulates cholesterol synthesis and the processing of sterol regulatory element binding proteins (SREBPs).
Pathway
Primary bile acid biosynthesis
Orthology
K10223  
cholesterol 25-hydroxylase
Genes
HSA: 
9023(CH25H)
PTR: 
450584(CH25H)
PPS: 
100974384(CH25H)
GGO: 
101125247(CH25H)
PON: 
100452872(CH25H)
MCC: 
694532(CH25H)
MMU: 
12642(Ch25h)
RNO: 
309527(Ch25h)
CFA: 
AML: 
FCA: 
101098893(CH25H)
BTA: 
506132(CH25H)
SSC: 
100157868
ECB: 
100062138
SHR: 
100930151(CH25H)
OAA: 
100078582
GGA: 
423788(CH25H)
MGP: 
100550290
TGU: 
100222744
ACS: 
100554078 100568259
XTR: 
100494906 100497262
DRE: 
336673(ch25hl1.1) 494109(ch25h)
TRU: 
101065133
OLA: 
101157212 101164274
BFO: 
BRAFLDRAFT_116078
SPU: 
583592
 » show all
Taxonomy
Reference
1  [PMID:9852097]
  Authors
Lund EG, Kerr TA, Sakai J, Li WP, Russell DW.
  Title
cDNA cloning of mouse and human cholesterol 25-hydroxylases, polytopic membrane proteins that synthesize a potent oxysterol regulator of lipid metabolism.
  Journal
J. Biol. Chem. 273 (1998) 34316-27.
  Organism
Homo sapiens [GN:hsa], Mus musculus [GN:mmu]
Reference
2  [PMID:11967195]
  Authors
Chen JJ, Lukyanenko Y, Hutson JC.
  Title
25-hydroxycholesterol is produced by testicular macrophages during the early postnatal period and influences differentiation of Leydig cells in vitro.
  Journal
Biol. Reprod. 66 (2002) 1336-41.
  Organism
Rattus norvegicus [GN:rno]
Reference
3  [PMID:12390873]
  Authors
Lukyanenko Y, Chen JJ, Hutson JC.
  Title
Testosterone regulates 25-hydroxycholesterol production in testicular macrophages.
  Journal
Biol. Reprod. 67 (2002) 1435-8.
  Organism
Rattus norvegicus [GN:rno]
Reference
4  [PMID:7947683]
  Authors
Fox BG, Shanklin J, Ai J, Loehr TM, Sanders-Loehr J.
  Title
Resonance Raman evidence for an Fe-O-Fe center in stearoyl-ACP desaturase. Primary sequence identity with other diiron-oxo proteins.
  Journal
Biochemistry. 33 (1994) 12776-86.
Reference
5  [PMID:12543708]
  Authors
Russell DW.
  Title
The enzymes, regulation, and genetics of bile acid synthesis.
  Journal
Annu. Rev. Biochem. 72 (2003) 137-74.
  Organism
Homo sapiens [GN:hsa]
Other DBs
ExplorEnz - The Enzyme Database: 
IUBMB Enzyme Nomenclature: 
ExPASy - ENZYME nomenclature database: 
BRENDA, the Enzyme Database: 
CAS: 
60202-07-5
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