View source for Biology:5beta-cholestane-3alpha,7alpha-diol 12alpha-hydroxylase

{{short description|Class of enzymes}}
{{infobox enzyme
| Name       = 5beta-cholestane-3alpha,7alpha-diol 12alpha-hydroxylase
| EC_number  = 1.14.13.96
| CAS_number =
| GO_code    = 
| image      = 
| width      = 
| caption    =  
}}

In [[Biology:Enzymology|enzymology]], a '''5beta-cholestane-3alpha,7alpha-diol 12alpha-hydroxylase''' ({{EC number|1.14.13.96}}) is an [[Biology:Enzyme|enzyme]] that [[Chemistry:Catalysis|catalyzes]] the [[Chemistry:Chemical reaction|chemical reaction]]

:5beta-cholestane-3alpha,7alpha-diol + NADPH + H<sup>+</sup> + O<sub>2</sub> <math>\rightleftharpoons</math> 5beta-cholestane-3alpha,7alpha,12alpha-triol + NADP<sup>+</sup> + H<sub>2</sub>O

The 4 [[Biology:Substrate (biochemistry)|substrates]] of this enzyme are 5beta-cholestane-3alpha,7alpha-diol, [[Chemistry:Nicotinamide adenine dinucleotide phosphate|NADPH]], [[Physics:Hydrogen ion|H<sup>+</sup>]], and [[Chemistry:Oxygen|O<sub>2</sub>]], whereas its 3 [[Chemistry:Product|products]] are 5beta-cholestane-3alpha,7alpha,12alpha-triol, [[Chemistry:Nicotinamide adenine dinucleotide phosphate|NADP<sup>+</sup>]], and [[Chemistry:Water|H<sub>2</sub>O]].

== Nomenclature ==

This enzyme belongs to the family of [[Biology:Oxidoreductase|oxidoreductase]]s, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with NADH or NADPH as one donor, and incorporation of one atom o oxygen into the other donor.  The [[Biology:List of enzymes|systematic name]] of this enzyme class is 5beta-cholestane-3alpha,7alpha-diol,NADPH:oxygen oxidoreductase (12alpha-hydroxylating). Other names in common use include 5beta-cholestane-3alpha,7alpha-diol 12alpha-monooxygenase, sterol 12alpha-hydroxylase (ambiguous), CYP8B1, and cytochrome P450 8B1.

== References ==
{{reflist}}

== Further reading ==
{{refbegin}}
* {{cite journal | vauthors = 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 = European Journal of Biochemistry | volume = 125 | issue = 2 | pages = 423–9 | date = July 1982 | pmid = 6811268 | doi = 10.1111/j.1432-1033.1982.tb06700.x | doi-access =  }}
* {{cite journal | vauthors = Hansson R, Wikvall K | title = Hydroxylations in biosynthesis and metabolism of bile acids. Catalytic properties of different forms of cytochrome P-450 | journal = The Journal of Biological Chemistry | volume = 255 | issue = 4 | pages = 1643–9 | date = February 1980 | pmid = 6766451 }}
* {{cite journal | vauthors = 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 = Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids | volume = 1634 | issue = 3 | pages = 86–96 | date = November 2003 | pmid = 14643796 | doi = 10.1016/j.bbalip.2003.09.002 }}
* {{cite journal | vauthors = Lukacin R, Matern U, Junghanns KT, Heskamp ML, Britsch L, Forkmann G, Martens S | title = Purification and antigenicity of flavone synthase I from irradiated parsley cells | journal = Archives of Biochemistry and Biophysics | volume = 393 | issue = 1 | pages = 177–83 | date = September 2001 | pmid = 11516175 | doi = 10.1006/abbi.2001.2491 }}
* {{cite journal | vauthors = 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 = Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids | volume = 1583 | issue = 1 | pages = 63–73 | date = June 2002 | pmid = 12069850 | doi = 10.1016/s1388-1981(02)00186-5 }}
* {{cite journal | vauthors = Russell DW | title = The enzymes, regulation, and genetics of bile acid synthesis | journal = Annual Review of Biochemistry | volume = 72 | issue = 1 | pages = 137–74 | date = 2003 | pmid = 12543708 | doi = 10.1146/annurev.biochem.72.121801.161712 }}
{{refend}}

{{Dioxygenases}}
{{Enzymes}}

[[Category:EC 1.14.13]]
[[Category:NADPH-dependent enzymes]]
[[Category:Enzymes of unknown structure]]



{{Sourceattribution|5beta-cholestane-3alpha,7alpha-diol 12alpha-hydroxylase}}