Center for Bioinformatics
Oxidoreductases | Transferases | Hydrolases | Lyases | Isomerases | Ligases

Basic Information

Enzyme Number

Official Name

cholestanetriol 26-monooxygenase

Name from literature

sterol 27-hydroxylase

Pathway from literature

the alternative pathway

Pathway from KEGG

Lipid Metabolism; Bile acid biosynthesis; map00120

Cellular Processes; Endocrine System; PPAR signaling pathway; map03320


Mouse (10090)

Genome localization

1 C3|1 43.1 cM[104086 ],


Requires ferrodoxin. Acts on cholesterol, cholest-5-en-3beta,7alpha-diol, 7alpha-hydroxycholest-4-en-3-one, 5beta-cholestane-3alpha,7alpha-diol as well as 5beta-cholestane-3alpha,7alpha,12alpha-triol. With cholesterol as well as 26-hydroxycholesterol, 24-hydroxy- and 25-hydroxycholesterol are also formed. With prolonged treatment, 26-hydroxycholesterol is converted into the corresponding 27-aldehyde and 27-oic acid.

Rate-limiting Description

"They are cholesterol 7alpha-hydroxylase (CYP7A1), the rate limiting enzyme in the classic pathway, sterol 12alpha-hydroxylase (CYP8B1), the key enzyme for synthesis of cholic acid (CA), and sterol 27-hydroxylase (CYP27), the initial enzyme in the alternative pathway." (15936349)

Gene ontology

Gene ontology

GO:0020037 (F) heme binding [Q9DBG1, Q6VVW9 ];
GO:0005506 (F) iron ion binding [Q9DBG1, Q6VVW9 ];
GO:0005789 (C) endoplasmic reticulum membrane [Q6VVW9 ];
GO:0042359 (P) vitamin D metabolic process [Q6VVW9 ];
GO:0047749 (F) cholestanetriol 26-monooxygenase activity [Q9DBG1, Q6VVW9 ];
GO:0009055 (F) electron carrier activity [Q9DBG1, Q6VVW9 ];
GO:0030343 (F) vitamin D3 25-hydroxylase activity [Q6VVW9 ];
GO:0005792 (C) microsome [Q6VVW9 ];
GO:0005743 (C) mitochondrial inner membrane [Q9DBG1 ];
GO:0055114 (P) oxidation reduction [Q9DBG1, Q6VVW9 ];

Subcellular localization


mitochondrion [Q9DBG1 ];

endoplasmic reticulum [Q6VVW9 ];

microsome [Q6VVW9 ];

membrane [Q6VVW9 ];




Entrez Gene


  Copyright 2009, Center for Bioinformatics 
  Last Modified: 2009-03-24  
  Design by Zhao Min