New publication in PNAS

Metabolic model for cable bacteria

Since their surprise discovery 7 years ago,  the centimeter-long, electricity-conducting cable bacteria have been equally fascinating and enigmatic to scientists worldwide: unique internal fibers under their skin likely act as wires to transport electrons along the chain of 10.000s of cells constituting a typical cable bacterium. Cable bacteria have been found globally in the seafloor and appear to remove toxic sulfide to the benefit of marine life.  But where did those peculiar living cables originate, and how do they actually work internally? These questions have been approached by an international team lead by professor Andreas Schramm from the Center for Electromicrobiology at Aarhus University which included Michael Wagner and Markus Schmid from DOME, and the results have now been published in PNAS. The paper includes a metabolic model for cable bacteria that contain many unexpected features: The anodic cells oxidize sulfide by reversing the pathway described for sulfate-reducers and the cathodic cells flare off the electrons for oxygen reduction without conserving energy. Why? Have a look at the paper.