title: Characterization of 6 alpha-hydroxylation of taurochenodeoxycholic acid in pig liver.
abstract: The properties of the species-specific 6 alpha-hydroxylation of taurochenodeoxycholic acid were studied in subcellular fractions from pig liver. The hydroxylation was observed in microsomes but not in mitochondria. A partially purified cytochrome P-450 fraction in the presence of NADPH-cytochrome P-450 reductase, NADPH, and phospholipid catalyzed 6 alpha-hydroxylation of taurochenodeoxycholic acid at a 160-fold higher rate than the microsomes. This cytochrome P-450 fraction did not catalyze 6 alpha-hydroxylation of 5 beta-cholestane-3 alpha,7 alpha-diol or testosterone, nor did it catalyze 7 alpha-hydroxylation of cholesterol.
mesh_terms: D000818:Animals; D002635:Chenodeoxycholic Acid / Q000031:analogs & derivatives*; D002784:Cholesterol / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D006900:Hydroxylation; D008099:Liver / Q000378:metabolism*; D008862:Microsomes, Liver / Q000378:metabolism; D008930:Mitochondria, Liver / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000378:metabolism; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism; D013552:Swine; D013655:Taurochenodeoxycholic Acid / Q000378:metabolism*; D013739:Testosterone / Q000378:metabolism
chemical_list: D002635:Chenodeoxycholic Acid; D013739:Testosterone; D013655:Taurochenodeoxycholic Acid; D003577:Cytochrome P-450 Enzyme System; D002784:Cholesterol; D006899:Mixed Function Oxygenases; D009251:NADPH-Ferrihemoprotein Reductase