Bile acids long have been known to play a role in human metabolism. Synthesized from cholesterol in the liver, bile acids are involved in digestive processes, particularly in absorbing fat. They also are modified extensively by bacteria, which greatly expand the types of bile acids found in the host.
For most of a century, scientists believed that was the end of the bile-acid story. Recent technological advances, however, have led to a greater understanding of the origins of bile acids as well as their chemical relationships to the organisms in the gut microbiome and their host. Deploying some of these technologies, a team led by Penn State researchers has uncovered the mechanism by which bacteria generate a wide variety of new bile acid species, the functions of which are not yet clear.
The researchers, who published their results recently in Nature, identified a new role for an old…
