Epimerization of chenodeoxycholic acid to ursodeoxycholic acid by Clostridium baratii isolated from human feces.
Ursodeoxycholic acid-producing bacteria are of clinical and industrial interest due to the multiple beneficial effects of this bile acid on human health. This work reports the first isolation of 7-epimerizing bacteria from feces of a healthy volunteer, on the basis of their capacity to epimerize the primary bile acid, chenodeoxycholic acid, to ursodeoxycholic acid. Five isolates were found to be active starting from unconjugated chenodeoxycholic acid and its tauro-conjugated homologue, but none of these strains could epimerize the glyco-conjugated form. Biochemical testing and 16S ribosomal DNA sequencing converged to show that all five isolates were closely related to Clostridium baratii (99% sequence similarity), suggesting that this bacterial species could be responsible at least partially, for this bioconversion in the human gut.
Lepercq
Pascale
P
Unité d'Ecologie et de Physiologie du Système Digestif, Institut National de la Recherche Agronomique, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France.
Gérard
Philippe
P
Béguet
Fabienne
F
Raibaud
Pierre
P
Grill
Jean-Pierre
JP
Relano
Purification
P
Cayuela
Chantal
C
Juste
Catherine
C
D000368:Aged; D002635:Chenodeoxycholic Acid / Q000737:chemistry / Q000378:metabolism*; D003013:Clostridium / Q000302:isolation & purification / Q000378:metabolism*; D005243:Feces / Q000382:microbiology*; D006801:Humans; D007536:Isomerism; D008297:Male; D014580:Ursodeoxycholic Acid / Q000737:chemistry / Q000378:metabolism*
D002635:Chenodeoxycholic Acid; D014580:Ursodeoxycholic Acid