Eyssen H, De Pauw G, Stragier J, Verhulst A
Appl Environ Microbiol. 1983 Jan;45(1):141-7. doi: 10.1128/aem.45.1.141-147.1983.
Three anaerobic bacteria, isolated from the ceca of rats and mice, converted, through a concerted mechanism, beta-muricholic acid, the predominant bile acid in germfree rats, into omega-muricholic acid. One isolate was a Eubacterium lentum strain; the second and third isolates were tentatively identified as atypical Fusobacterium sp. strains. The conversion of beta-muricholic acid into omega-muricholic acid proceeded in two steps: E. lentum oxidized the 6 beta-hydroxyl group of beta-muricholic acid to a 6-oxo group, which was reduced by either of the two other species to a 6 alpha-hydroxyl group, yielding omega-muricholic acid. This transformation occurred both in vitro and in gnotobiotic rats. Monoassociation of germfree rats with the E. lentum strain gave rise to an unidentified fecal bile acid, probably a derivative of beta-muricholic acid having a double bond in the side chain.
从大鼠和小鼠盲肠中分离出的三种厌氧细菌，通过协同机制将无菌大鼠体内主要的胆汁酸β-鼠胆酸转化为ω-鼠胆酸。其中一种分离菌是迟缓真杆菌菌株；另外两种分离菌初步鉴定为非典型梭杆菌属菌株。β-鼠胆酸向ω-鼠胆酸的转化分两步进行：迟缓真杆菌将β-鼠胆酸的6β-羟基氧化为6-氧代基团，另外两种菌中的任何一种再将其还原为6α-羟基，从而生成ω-鼠胆酸。这种转化在体外和悉生大鼠体内均会发生。无菌大鼠与迟缓真杆菌菌株单联后产生了一种未鉴定的粪便胆汁酸，可能是β-鼠胆酸在侧链上有双键的衍生物。
