Fluorogenic substrates and pre-column derivatization for monitoring the activity of bile salt hydrolase from Clostridium perfringens

The bile acid pool has a profound impact on human health and disease. The intestinal microbiota initiates the metabolism of conjugated bile acids through a critical first step catalyzed by bacterial bile salt hydrolase (BSH) and provides unique contributions to the diversity of bile acids. There has been great interest in surveying BSH activity. We compared two substrates with either 2-(7-amino-4-methyl-coumarinyl)acetic acid or 7-amino-4-methyl-coumarin as fluorescent reporters of BSH activity. The BSH-catalyzed conversion of the natural substrate taurocholic acid was followed through an HPLC-based assay by applying 7-nitrobenzo[c] [1,2,5]oxadiazole as scavenger for taurine, released in the enzymatic reaction. Hence, a new opportunity to monitor the activity of bile salt hydrolases was introduced.

Automated summary

The bile acid pool has a significant impact on human health and disease. The intestinal microbiota plays a critical role in the metabolism and diversity of bile acids through the action of bacterial bile salt hydrolase (BSH). This study introduces a new method to monitor BSH activity using fluorescent reporters and an HPLC-based assay.