title: The gut anaerobe Faecalibacterium prausnitzii uses an extracellular electron shuttle to grow at oxic-anoxic interphases.
abstract: Faecalibacterium prausnitzii is one of the most abundant bacteria in the human gut ecosystem and it is an important supplier of butyrate to the colonic epithelium. Low numbers of faecalibacteria have been associated with inflammatory bowel disease. Despite being extremely oxygen sensitive, F. prausnitzii is found adherent to the gut mucosa where oxygen diffuses from epithelial cells. This paradox is now explained on the basis of gas tube experiments, flavin-dependent reduction of 5,5'-dithiobis-2-nitrobenzoate and microbial fuel cell experiments. The results show that F. prausnitzii employs an extracellular electron shuttle of flavins and thiols to transfer electrons to oxygen. Both compounds are present in the healthy human gut. Our observations may have important implications for the treatment of patients with Crohn's disease, for example, with flavin- or antioxidant rich diets, and they provide a novel key insight in host-microbe interactions at the gut barrier.
authors.affiliation: Department of Medical Microbiology, University Medical Center Groningen, University of Groningen, The Netherlands.
authors.forename: M Tanweer
authors.initials: MT
authors.lastname: Khan
authors.forename: Sylvia H
authors.initials: SH
authors.lastname: Duncan
authors.forename: Alfons J M
authors.initials: AJ
authors.lastname: Stams
authors.forename: Jan Maarten
authors.initials: JM
authors.lastname: van Dijl
authors.forename: Harry J
authors.initials: HJ
authors.lastname: Flint
authors.forename: Hermie J M
authors.initials: HJ
authors.lastname: Harmsen
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D004583:Electrons; D005110:Extracellular Space / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006094:Gram-Positive Bacteria / Q000254:growth & development* / Q000378:metabolism*; D006801:Humans; D010100:Oxygen / Q000378:metabolism*; D012256:Riboflavin / Q000378:metabolism
chemical_list: D010100:Oxygen; D012256:Riboflavin