Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
NC State Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA.
Chembiochem. 2020 Dec 11;21(24):3539-3543. doi: 10.1002/cbic.202000370. Epub 2020 Oct 7.
Animals produce bile to act as an antibacterial agent and to maximize the absorption of lipophilic nutrients in the gut. The physical properties of bile are largely dictated by amphipathic bile salt molecules, which also participate in signaling pathways by modulating physiological processes upon binding host receptors. Upon excretion of bile salts from the gall bladder into the intestine, the gut microbiota can create metabolites with modified signaling capabilities. The category and magnitude of bile salt metabolism can have positive or negative effects on the host. A key modification is bile salt hydrolysis, which is a prerequisite for all additional microbial transformations. We have synthesized five different fluorogenic bile salts for simple and continuous reporting of hydrolysis in both murine and human fecal samples. Our data demonstrate that most gut microbiomes have the highest capacity for hydrolysis of host-produced primary bile salts, but some microbially modified secondary bile salts also display significant turnover.
动物产生胆汁以起到抗菌作用，并最大限度地吸收肠道内的脂溶性营养素。胆汁的物理性质主要由两亲性胆汁盐分子决定，这些分子在与宿主受体结合后，通过调节生理过程，也参与信号通路。当胆汁盐从胆囊排入肠道时，肠道微生物群可以产生具有修饰信号能力的代谢物。胆汁盐代谢的类别和程度可能对宿主产生积极或消极的影响。一个关键的修饰是胆汁盐水解，这是所有其他微生物转化的前提。我们合成了五种不同的荧光胆汁盐，用于简单、连续地报告鼠和人粪便样本中的水解情况。我们的数据表明，大多数肠道微生物组对宿主产生的初级胆汁盐具有最高的水解能力，但一些微生物修饰的次级胆汁盐也显示出显著的周转率。
