About Microbial Bile Acids

Recently the Quinn and Dorrestein Labs made the remarkable discovery that our gut bacteria produce a unique set of bile acids that represent a 5th mechanism of bile acid metabolism. These microbial conjugated bile acids (MCBAs) are created by combining various amino acids to the acyl-site of the host produced cholic acid. These compounds have evaded characterization despite over 170 years of research on bile chemistry. They are found particularly in the guts of people with disease, such as Crohne’s disease and cystic fibrosis, and are even present in infants as early as 2-weeks of age. The discovery of these molecules represents a sea change in our understanding of human bile. The Quinn lab is currently investigating how they are produced by our microbiota and their effects on our physiology.