Science Daily  March 20, 2024 Extracellular electron transfer (EET) via microbial nanowires drives important environmental processes and biotechnological applications for bioenergy, bioremediation, and bioelectronics. However, the process is not clear. An international team of researchers (USA – Yale University, Portugal) showed that Geobacter sulfurreducens periplasmic cytochromes PpcABCDE inject electrons directly into OmcS nanowires by binding transiently with differing efficiencies, with the least-abundant cytochrome (PpcC) showing the highest efficiency. This defined nanowire-charging pathway was evolutionarily conserved in phylogenetically diverse bacteria capable of EET. OmcS heme reduction potentials were within 200 mV of each other, with a midpoint 82 mV-higher than reported previously. […]