A glycyl radical enzyme enables hydrogen sulfide production by the human intestinal bacterium Bilophila wadsworthia
Abstract
This paper describes a pathway for anaerobic bacterial metabolism of taurine (2-aminoethanesulfonate), an abundant substrate in the human intestinal microbiota, by the intestinal bacterium and opportunistic pathogen, Bilophila wadsworthia. This metabolism converts taurine to the toxic metabolite hydrogen sulfide (H2S), an activity associated with inflammatory bowel disease and colorectal cancer. A critical enzyme in this pathway is isethionate sulfite-lyase, a member of the glycyl radical enzyme family. This enzyme catalyzes a novel, radical-based C-S bond-cleavage reaction to convert isethionate (2-hydroxyethanesulfonate) to sulfite and acetaldehyde. This discovery improves our understanding of H2S production in the human body and may also offer new approaches for controlling intestinal H2S production and B. wadsworthia infections.
- Publication:
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Proceedings of the National Academy of Science
- Pub Date:
- February 2019
- DOI:
- 10.1073/pnas.1815661116
- Bibcode:
- 2019PNAS..116.3171P