Long-distance electron transport occurs globally in marine sediments

Laurine D. W. Burdorf, Anton Tramper, Dorina Seitaj, Lorenz Meire, Silvia Hidalgo-Martinez, Eva-Maria Zetsche, Henricus T. S. Boschker, Filip J. R. Meysman
2016 Biogeosciences Discussions  
Recently, long filamentous bacteria have been reported to conduct electrons over centimetre distances in marine sediments. These so-called cable bacteria perform a novel "electrogenic" form of sulfur oxidation, whereby long-distance electron transport links sulfide oxidation in deeper sediment horizons to oxygen reduction in the upper millimetres of the sediment. Electrogenic sulfur oxidation exerts a strong impact on the sediment biogeochemistry, but it is currently unknown how prevalent the
more » ... how prevalent the process is within the seafloor. Here we provide a state-of-the-art assessment of its global distribution by combining new field observations with previous reports from literature. This synthesis demonstrates that electrogenic sulfur oxidation mediated by long-distance electron transport is a widespread phenomenon in the present-day seafloor. The process is found in different oceanographic regions and climate zones (The Netherlands, Greenland, USA, Australia), and thrives in a range of different coastal habitats (estuaries, salt marshes, mangroves, coastal hypoxic basins, intertidal flats). The combination of a widespread occurrence and a strong local geochemical imprint suggests that electrogenic sulfur oxidation could be an important, and hitherto overlooked, component of the marine cycle of carbon, sulfur and other elements.
doi:10.5194/bg-2016-362 fatcat:ri45nk6bmvdapjww4yrnrfuaha