A Microbiome Atlas

Microbiome-encoded β-glucuronidase, GUS, enzymes play important roles in human health by metabolizing drugs in the gastrointestinal, GI, tract. The numbers, types, and diversity of these proteins in the human GI microbiome, however, remain undefined.

Published in the journal Structure, researchers in the Redinbo Group, in collaboration with colleagues at the University of Florida, present an atlas of GUS enzymes comprehensive for the Human Microbiome Project GI database.

The group members identify 3,013 total and 279 unique microbiome-encoded GUS proteins clustered into six unique structural categories. They assign their taxonomy, assess cellular localization, reveal the inter-individual variability within the 139 individuals sampled, and discover 112 novel microbial GUS enzymes.

A representative in vitro panel of the most common GUS proteins by read abundances highlights structural and functional variabilities within the family, including their differential processing of smaller glucuronides and larger carbohydrates.

The information outlined in this study could form a basis for personalized medicine and predictive efforts to identify patients at risk for chemotherapy-induced diarrhea, for example. Such knowledge may facilitate regimen-tailoring to enhance anti-tumor efficacy while avoiding dose-limiting GI toxicities, or could suggest dietary changes that could improve microbiota composition before treatment.

Taken together, the data and methodologies presented provide a roadmap for the annotation of diverse microbiome-encoded catalytic and non-catalytic functions, and open the door to new eras of discovery in understanding mammalian-microbial mutualism.