Redox conduction in biofilms: From respiration to living electronics

Recent studies of electrochemically active bacteria paint a mechanistic picture where multistep hopping of electrons can be driven by redox gradients, allowing electron conduction over length scales previously thought impossible in biological systems. This review explores these observations from an electrochemical and biophysical perspective, with emphasis on the role of metalloproteins such as the multiheme extracellular electron transport conduits thought to mediate this transport. Since these conduits naturally evolved to interact with external surfaces, a fundamental understanding has special implications for a new generation of bioelectrochemical technologies and living electronics that wire bacteria to electrodes.