Metatranscriptomics-guided discovery and characterization of a polyphenol-metabolizing gut microbial enzyme
Minwoo Bae, Chi Hieu Le, Raaj S. Mehta, Xueyang Dong, Lindsey M. Pieper, Lorenzo Ramirez, Margaret Alexander, Sina Kiamehr, Peter J. Turnbaugh, Curtis Huttenhower, Andrew T. Chan, Emily P. Balskus
Abstract
Gut microbial catechol dehydroxylases are a largely uncharacterized family of metalloenzymes that potentially impact human health by metabolizing dietary polyphenols. Here, we use metatranscriptomics (MTX) to identify highly transcribed catechol-dehydroxylase-encoding genes in human gut microbiomes. We discover a prevalent, previously uncharacterized catechol dehydroxylase (Gp Hcdh) from Gordonibacter pamelaeae that dehydroxylates hydrocaffeic acid (HCA), an anti-inflammatory gut microbial metabolite derived from plant-based foods. Further analyses suggest that the activity of Gp Hcdh may reduce anti-inflammatory benefits of polyphenol-rich foods. Together, these results show the utility of combining MTX analysis and biochemical characterization for gut microbial enzyme discovery and reveal a potential link between host inflammation and a specific polyphenol-metabolizing gut microbial enzyme.