The overwhelming majority of organisms use oxygen to metabolize energy since oxygen accepts electrons well.
Bacteria living in these oxygen-limited atmospheres replace oxygen with iron. And instead of the metabolic reactions happening inside cells, the microorganism transfers electrons into the external atmosphere on thin protein filaments. They create electrical energy.
A new study by research associates at the University of Massachusetts Amherst reveals that pili—tiny filaments projecting out from microorganism—can be utilized to create wires used in biosensors and bioelectronics. The electrical microorganism uses their pili to conduct electricity long-range, which permits them to meet other microorganisms or minerals in the atmosphere electrically.
Recently, the researchers discovered a member of Archaea, Methanospirillum hungatei, which can conduct electricity. Fortuitously, other researchers had already documented the precise structure of the particular protein filament M. hungatei uses to perform electrical energy over long ranges, so this uncovers extremely promising for the event of “green” digital materials that could be sustainably built by microbes.
The filaments could be provided as “a revolutionary, sustainably generated, electronic materials with broad potential purposes.” Particularly, protein nanowires structured like the filaments from M. hungatei would be a significant advance over the existing empirical design of artificial protein nanowires from electrically conductive bacterial pili. Nanowires generated by microbes have specific properties that have not been seen in different nanowire materials.
Other purposes include bioelectrochemical units or anaerobic digesters that convert waste into natural gas.
Microbial nanowires would be simpler for individuals to wear or have implanted in their bodies because the wires don’t dissolve in wire or biological fluids.