biostudies-literatureUnknownLucas LNNIDDK NIH HHSNHLBI NIH HHSNIGMS NIH HHSThrough biochemical transformation of host-derived bile acids (BAs), gut bacteria mediate host-microbe crosstalk and sit at the interface of nutrition, the microbiome, and disease. BAs play a crucial role in human health by facilitating the absorption of dietary lipophilic nutrients, interacting with hormone receptors to regulate host physiology, and shaping gut microbiota composition through antimicrobial activity. Bile acid deconjugation by bacterial bile salt hydrolase (BSH) has long been recognized as the first necessary BA modification required before further transformations can occur. Here, we show that BSH activity is common among human gut bacterial isolates spanning seven major phyla. We observed variation in both the extent and the specificity of deconjugation of BAs among the tebioRxiv : the preprint server for biology2025.01.16.633392https://www.ebi.ac.uk/biostudies/studies/S-EPMC11760432biostudies-literatureInvestigation of Bile Salt Hydrolase Activity in Human Gut Bacteria Reveals Production of Conjugated Secondary Bile Acids.PMC11760432R01 HL148577T32 GM135066T32 DK007665Stevenson DAmador-Noguez DMallikarjun JCattaneo LEKerby RLLucas LNRey FEZhang QGangwar BfalseInvestigation of Bile Salt Hydrolase Activity in Human Gut Bacteria Reveals Production of Conjugated Secondary Bile Acids.Through biochemical transformation of host-derived bile acids (BAs), gut bacteria mediate host-microbe crosstalk and sit at the interface of nutrition, the microbiome, and disease. BAs play a crucial role in human health by facilitating the absorption of dietary lipophilic nutrients, interacting with hormone receptors to regulate host physiology, and shaping gut microbiota composition through antimicrobial activity. Bile acid deconjugation by bacterial bile salt hydrolase (BSH) has long been recognized as the first necessary BA modification required before further transformations can occur. Here, we show that BSH activity is common among human gut bacterial isolates spanning seven major phyla. We observed variation in both the extent and the specificity of deconjugation of BAs among the te2025-01-01T00:00:00Z2025 Jan2025-04-04T02:01:25.804Z2025-04-04T02:01:25.804ZS-EPMC117604323986827110.1101/2025.01.16.633392