Degradation of steroids by intestinal bacteria. I. Deconjugation of bile salts

1. 1. Cholanylglycine hydrolase has been studied in cell fractions from two faecal strains of each of the genera: Enterococcus, Clostridium, Bifidobacterium and Bacteroides. 2. 2. Intracellular and extracellular fractions with bile deconjugating ability have been characterized for substrate specificity, product inhibition, pH optimum and for the effect of a range of inhibitors. 3. 3. All preparations showed similar properties in their response to inhibitors and in their pH optimum of 5–6. All were more stable under reducing conditions. We suggest that anaerobic conditions are necessary in vivo for optimal production and stability of cholanylglycine hydrolase from faecal bacteria.