Desulfosporosinus facilitated the electrode-driven dechlorination by Dehalococcoides via interspecies hydrogen transfer

Microbial communities involving electroactive bacteria assist in bioelectrochemical dechlorination by Dehalococcoides (Dhc.). To understand the interactions between electroactive bacteria and Dhc., the functional electroactive bacteria which potentially contributed to bioelectrochemical dechlorination by Dhc. was enriched by inoculating the cathode cell with Dhc. and paddy soil. Furthermore, the predicted functional species, Desulfosporosinus meridiei was co-cultured with Dhc. under an applied voltage of -0.3 V (versus a standard hydrogen electrode). The results show that long-term dechlorination stability can be lasted more than 200 days via the interaction between Dhc. and soil microorganisms. Dehalococcoides/Desulfosporosinus co-cultures improved the approximately 4 times higher maximum ethylene production rate than that in the monoculture of Dhc.. Desulfosporosinus enhanced the dechlorination by Dhc. mainly via interspecies hydrogen transfer. The study provides an important theoretical basis for revealing the function of electroactive bacteria on the bioelectrochemical dehalogenation.