Identification of CYP3A4 as the major enzyme responsible for 25-hydroxylation of 5β-cholestane-3α, 7α, 12α-triol in human liver microsomes
C Furster, K Wikvall - Biochimica et Biophysica Acta (BBA)-Molecular and …, 1999 - Elsevier
Human liver microsomes catalyze an efficient 25-hydroxylation of 5β-cholestane-3α, 7α, 12α-
triol. The hydroxylation is involved in a minor, alternative pathway for side-chain degradation
in the biosynthesis of cholic acid. The enzyme responsible for the microsomal 25-
hydroxylation has been unidentified. In the present study, recombinant expressed human P-
450 enzymes have been used to screen for 25-hydroxylase activity towards 5β-cholestane-
3α, 7α, 12α-triol. High activity was found with CYP3A4, but also with CYP3A5 and to a minor …
triol. The hydroxylation is involved in a minor, alternative pathway for side-chain degradation
in the biosynthesis of cholic acid. The enzyme responsible for the microsomal 25-
hydroxylation has been unidentified. In the present study, recombinant expressed human P-
450 enzymes have been used to screen for 25-hydroxylase activity towards 5β-cholestane-
3α, 7α, 12α-triol. High activity was found with CYP3A4, but also with CYP3A5 and to a minor …