Fig. 7: Predicted electromethanogenic pathway of Methanomasilliicoccus luminyensis.

Extracellular electrons from C. malenominatum or cathode are accepted by the M. luminyensis Pili and transferred to, or directed accepted by the membrane bound Fpo-like complex. Electrons are then transferred to membrane associated HdrD to reduce heterodisulfide CoM-S-S-CoB for methane production from methanol (MeOH) or trimethylamine (TMA). Protein icons shadowed in purple, blue and gray represent the encoding genes to be up- and down-regulated, and no change when M. luminyensis uses extracellular electron versus H2. MT methylotransferase, MCR methyl-CoM reductase.