Bile salt hydrolase–producing bacterium (BSH-producing bacterium)

Bile salt hydrolase–producing bacteria are a broad group of gut microbes distinguished by their production of the enzyme bile salt hydrolase (BSH, EC 3.5.1.24), which catalyzes the hydrolysis (deconjugation) of glycine- or taurine-conjugated bile acids into free bile acids and amino acids. This reaction is the gateway step in gut bile acid transformation and crucial for the formation of secondary bile acids, shaping the gut microbial ecology and diverse aspects of host metabolism, immunity, and cholesterol homeostasis. Major BSH-producing taxa include species of Lactobacillus, Bifidobacterium, Clostridium, Enterococcus, and Bacteroides. The gene and protein product, BSH, is a member of the N-terminal nucleophilic hydrolase family. Interest in BSH-producing bacteria as a therapeutic target stems from their role in cholesterol lowering (via enhanced bile acid deconjugation and excretion), metabolic syndrome, and the potential to modulate gut and hepatic diseases via manipulation of the bile acid pool. However, because this "target" represents a functional microbial group rather than a single molecular entity, it is considered an imprecise molecular target for drug development.

Other names

BSH-producing bacteriaGut microbial bile salt hydrolase–positive bacteriaProbiotic bile salt hydrolase producersMicroorganisms with bile salt hydrolase activity

Inhibitors: Reduce BSH activity, alter bile acid pool composition, increase conjugated bile acids. Probiotic supplementation: Increases BSH activity, enhances deconjugation, may lower cholesterol.