NR1H4 and infection: While all FXR KO mice experienced a large decrease in clostridial species from the family Lachnospiraceae, a concurrent infection with H. hepaticus might allow 7α-dehydroxylating, anaerobic bacteria, such as Clostridium scindens VPI 12708, C. hiranonis DSM 13275, and C. hylemonae DSM 15053 [35]–[38], to increase in abundance, and promote LCA synthesis through metabolism of the primary bile acid chenodeoxycholic acid (CDCA) [13].