biostudies-literatureWalker DJFUnited States Department of Defense | United States Army | U.S. Army Research, Development and Engineering Command | Army Research OfficeThis research was supported in part by the Army Research Office.Novo Nordisk Fonden837-846https://www.ebi.ac.uk/biostudies/studies/S-EPMC7031330biostudies-literatureUnknown14(3)Syntrophic interspecies electron exchange is essential for the stable functioning of diverse anaerobic microbial communities. Hydrogen/formate interspecies electron transfer (HFIT), in which H₂ and/or formate function as diffusible electron carriers, has been considered to be the primary mechanism for electron transfer because most common syntrophs were thought to lack biochemical components, such as electrically conductive pili (e-pili), necessary for direct interspecies electron transfer (DIET). Here we report that Syntrophus aciditrophicus, one of the most intensively studied microbial models for HFIT, produces e-pili and can grow via DIET. Heterologous expression of the putative S. aciditrophicus type IV pilin gene in Geobacter sulfurreducens yielded conductive pili of the sThe ISME journalSyntrophus conductive pili demonstrate that common hydrogen-donating syntrophs can have a direct electron transfer option.PMC7031330W911NF-17-1-0345NNF15OC0015220McInerney MJRotaru AEZhu JLovley DRNevin KPWard JENonnenmann SSWalker DJFHolmes DEWoodard TLUeki TfalseSyntrophus conductive pili demonstrate that common hydrogen-donating syntrophs can have a direct electron transfer option.Syntrophic interspecies electron exchange is essential for the stable functioning of diverse anaerobic microbial communities. Hydrogen/formate interspecies electron transfer (HFIT), in which H₂ and/or formate function as diffusible electron carriers, has been considered to be the primary mechanism for electron transfer because most common syntrophs were thought to lack biochemical components, such as electrically conductive pili (e-pili), necessary for direct interspecies electron transfer (DIET). Here we report that Syntrophus aciditrophicus, one of the most intensively studied microbial models for HFIT, produces e-pili and can grow via DIET. Heterologous expression of the putative S. aciditrophicus type IV pilin gene in Geobacter sulfurreducens yielded conductive pili of the s2020-01-01T00:00:00Z2020 Mar2025-04-19T02:19:49.493Z2021-03-03T08:14:16ZS-EPMC70313303189679210.1038/s41396-019-0575-9