Cable Bacteria Take a New Breath Using Long-Distance Electricity

Abstract

Recently, a new group of multicellular microorganisms was discovered, called 'cable bacteria', which are capable of generating and mediating electrical currents across centimetre-scale distances. By transporting electrons from cell to cell, cable bacteria can harvest electron donors and electron acceptors that are widely separated in space, thus providing them with a competitive advantage for survival in aquatic sediments. The underlying process of long-distance electron transport challenges some long-held ideas about the energy metabolism of multicellular organisms and entails a whole new type of electrical cooperation between cells. This review summarizes the current knowledge about these intriguing multicellular bacteria. Cable bacteria are a newly discovered group of multicellular bacteria that generate and mediate electrical currents along their long filamentous body.Long-distance electron transport by cable bacteria bridges centimeter distances and extends the known length scale of biological electron transport by orders of magnitude.Long-distance electron transport allows cable bacteria to harvest electron donors and electron acceptors in widely separated locations, thus challenging long-held ideas on redox zonation in subsurface environments.By generating electrical currents, cable bacteria induce measurable electrical fields and potentials within their environment, and turn aquatic sediments into a living battery.Their widespread occurrence and strong imprint on local biogeochemistry suggests that cable bacteria are important in the cycling of carbon, sulfur, and other elements.