The discovery of filamentous Desulfobulbaceae in 2012 elucidates the cause of the small electric currents measured in the top layer of marine sediment.[1] The currents were first measured in 2010.[2] These organisms, referred to as "cable bacteria", consist in thousands of cells arranged in filaments up to three centimeters in length. They transport electrons from the sediment that is rich in hydrogen sulfide up to the oxygen-rich sediment that is in contact with the water.[1][3][4][5][6] Later investigations revealed their ability to use nitrate or nitrite as final electron acceptor in absence of oxygen[7][8] Since the discovery, cable bacteria have been reported from a wide variety of sediments worldwide.[9] Based on phylogenetic analysis of 16s rRNA and dsrAB genes it was proposed to allocate cable bacteria within two novel candidate genera i.e. Ca. Electrothrix and Ca. Electronema.[10]
^ abPfeffer C, Larsen S, Song J, Dong M, Besenbacher F, Meyer RL, Kjeldsen KU, Schreiber L, Gorby YA, El-Naggar MY, Leung KM, Schramm A, Risgaard-Petersen N, Nielsen LP (November 2012). "Filamentous bacteria transport electrons over centimetre distances". Nature. 491 (7423): 218–21. doi:10.1038/nature11586. PMID23103872.
^Larsen S, Nielsen LP, Schramm A (April 2015). "Cable bacteria associated with long-distance electron transport in New England salt marsh sediment". Environmental Microbiology Reports. 7 (2): 175–9. doi:10.1111/1758-2229.12216. PMID25224178.
^Risgaard-Petersen N, Damgaard LR, Revil A, Nielsen LP (2014-08-01). "Mapping electron sources and sinks in a marine biogeobattery". Journal of Geophysical Research: Biogeosciences. 119 (8): 1475–1486. doi:10.1002/2014jg002673.