Bile acids (BA), the major components of bile, are biological detergents that facilitate the emulsification and solubilization of dietary lipids and also display potent antimicrobial activity, the bacterial membranes being their main targets. Considering the complicated nature of the stress produced by bile and BA, the microorganism tolerance requires different defence mechanisms including the presence of efflux pumps, bile salt hydrolase (BSH) enzyme, the intrinsic capacity of cells to maintain intracellular homeostasis and modifications in the architecture and composition of the cell membrane. Besides, the expression of proteins involved in carbohydrate and fatty acid metabolism, amino acid and nitrogenous base biosynthesis, and general stress response are commonly affected by the presence of bile. Among the microbial transformations, deconjugation of BA by BSH is the most important. Several studies indicate that BSH activity affects both the host physiology and the microbiota. In fact, it was strongly suggested that BSH could play an important role in the colonization and survival of bacteria in the gut. Also, recent work has shown that BSH and free BA participate in a variety of metabolic processes that include regulation of dietary lipid absorption, cholesterol metabolism, and energy and inflammation homeostasis.

In this review we summarize recent advances in the understanding of the mechanisms involved in the tolerance of bacteria to bile, with special emphasis on the contributions of studies applying an omic approach. Besides, the physiological and ecological role of BSH enzyme and its relevance to human health as well as the function of bile acid as metabolic regulator are also discussed.

胆汁酸（BA）是胆汁的主要成分，是生物清洁剂，可促进膳食脂质的乳化和增溶，并具有强大的抗菌活性，细菌膜是其主要目标。考虑到胆汁和BA产生的应激的复杂性质，对微生物的耐受性需要不同的防御机制，包括外排泵，胆汁盐水解酶（BSH）酶的存在，细胞维持细胞内稳态的固有能力以及结构和结构的改变。细胞膜的组成。此外，胆汁的存在通常会影响参与碳水化合物和脂肪酸代谢，氨基酸和氮基生物合成以及一般应激反应的蛋白质的表达。在微生物转化中，BSH对BA的解偶联作用是最重要的。多项研究表明，BSH活性会影响宿主生理和微生物群。实际上，强烈建议BSH在肠道细菌的定殖和存活中起重要作用。同样，最近的研究表明，BSH和游离BA参与多种代谢过程，包括调节饮食中的脂质吸收，胆固醇代谢以及能量和炎症稳态。

在这次审查中，我们总结了参与细菌的耐受胆汁，特别强调研究施加捐款的机制的了解最新进展OMIC方法。此外，还讨论了BSH酶的生理和生态作用及其与人体健康的关系，以及胆汁酸作为代谢调节剂的功能。