title: Stereospecific formation of (24R,25R)-3 alpha,7 alpha,12 alpha,24-tetrahydroxy-5 beta-cholestan-26-oic acid catalyzed with a peroxisomal bifunctional D-3-hydroxyacyl-CoA dehydratase/D-3-hydroxyacyl-CoA dehydrogenase.
abstract: The absolute configuration of 3 alpha,7 alpha,12 alpha, 24-tetrahydroxy-5 beta-cholestan-26-oic acid CoA ester (V-CoA) produced by the incubation of (24E)-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholest-24-en-26-oic acid CoA ester (24E-THC-CoA) with D-3-hydroxyacyl-CoA dehydratase/D-3-hydroxyacyl-CoA dehydrogenase (D-bifunctional protein) was investigated. When 24E-THC-CoA was incubated with D-bifunctional protein the formation of only one isomer (24R,25R-isomer) of four possible stereoisomers of V-CoA was observed, which suggested the cis-addition of water to a side chain double bond of 24E-THC-CoA. The dehydration reaction of V-CoA catalyzed by D-bifunctional protein was also observed when (24R,25R)-V-CoA was used as a substrate. The other three isomers (24R,25S-, 24S,25R- and 24S,25S-isomers) were not dehydrated with D-bifunctional protein. These results showed that D-bifunctional protein catalyzes stereospecifically the hydration and dehydration step in bile acid biosynthesis.
authors.affiliation: Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kurosawa
authors.forename: M
authors.initials: M
authors.lastname: Sato
authors.forename: T
authors.initials: T
authors.lastname: Yoshimura
authors.forename: L L
authors.initials: LL
authors.lastname: Jiang
authors.forename: T
authors.initials: T
authors.lastname: Hashimoto
authors.forename: M
authors.initials: M
authors.lastname: Tohma
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases; D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000378:metabolism*; D000818:Animals; D001647:Bile Acids and Salts / Q000096:biosynthesis; D002793:Cholic Acids / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004746:Enoyl-CoA Hydratase / Q000378:metabolism*; D006836:Hydro-Lyases / Q000378:metabolism*; D066298:In Vitro Techniques; D008862:Microsomes, Liver / Q000201:enzymology; D009097:Multienzyme Complexes / Q000378:metabolism*; D064029:Peroxisomal Multifunctional Protein-2; D011506:Proteins / Q000378:metabolism; D051381:Rats; D012503:Saponins / Q000378:metabolism*; D013237:Stereoisomerism; D014166:Transferases / Q000378:metabolism; D014315:Triterpenes
chemical_list: C096561:3,7,12,19-tetrahydroxycholanoic acid; D001647:Bile Acids and Salts; D002793:Cholic Acids; D009097:Multienzyme Complexes; D011506:Proteins; D012503:Saponins; D014315:Triterpenes; C106188:dammarenediol; D015067:17-Hydroxysteroid Dehydrogenases; D015094:3-Hydroxyacyl CoA Dehydrogenases; C491286:Hsd17b4 protein, rat; D014166:Transferases; D006836:Hydro-Lyases; D064029:Peroxisomal Multifunctional Protein-2; D004746:Enoyl-CoA Hydratase