The Identification of Cable Bacteria Attached to the Anode of a Benthic Microbial Fuel Cell: Evidence of Long Distance Extracellular Electron Transport to Electrodes
Multicellular, filamentous, sulfur-oxidizing bacteria, known as cable bacteria, were discovered attached to fibers of a carbon brush electrode serving as an anode of a benthic microbial fuel cell (BMFC). The BMFC had been operated in a temperate estuarine environment for over a year before collectin...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2017-10-01
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| Series: | Frontiers in Microbiology |
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| Online Access: | http://journal.frontiersin.org/article/10.3389/fmicb.2017.02055/full |
| _version_ | 1811313424263544832 |
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| author | Clare E. Reimers Cheng Li Michael F. Graw Paul S. Schrader Michael Wolf |
| author_facet | Clare E. Reimers Cheng Li Michael F. Graw Paul S. Schrader Michael Wolf |
| author_sort | Clare E. Reimers |
| collection | DOAJ |
| description | Multicellular, filamentous, sulfur-oxidizing bacteria, known as cable bacteria, were discovered attached to fibers of a carbon brush electrode serving as an anode of a benthic microbial fuel cell (BMFC). The BMFC had been operated in a temperate estuarine environment for over a year before collecting anode samples for scanning electron microscopy and phylogenetic analyses. Individual filaments were attached by single terminus cells with networks of pilus-like nano-filaments radiating out from these cells, across the anode fiber surface, and between adjacent attachment locations. Current harvesting by the BMFC poised the anode at potentials of ~170–250 mV vs. SHE, and these surface potentials appear to have allowed the cable bacteria to use the anode as an electron acceptor in a completely anaerobic environment. A combination of catalyzed reporter deposition fluorescent in situ hybridization (CARD-FISH) and 16S rRNA gene sequence analysis confirmed the phylogeny of the cable bacteria and showed that filaments often occurred in bundles and in close association with members of the genera Desulfuromonas. However, the Desulfobulbaceae Operational Taxonomic Units (OTUs) from the 16S sequencing did not cluster closely with other putative cable bacteria sequences suggesting that the taxonomic delineation of cable bacteria is far from complete. |
| first_indexed | 2024-04-13T10:53:35Z |
| format | Article |
| id | doaj.art-9407b51e6bc946f7ab98d3263a7f4f5b |
| institution | Directory Open Access Journal |
| issn | 1664-302X |
| language | English |
| last_indexed | 2024-04-13T10:53:35Z |
| publishDate | 2017-10-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Microbiology |
| spelling | doaj.art-9407b51e6bc946f7ab98d3263a7f4f5b2022-12-22T02:49:35ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2017-10-01810.3389/fmicb.2017.02055291990The Identification of Cable Bacteria Attached to the Anode of a Benthic Microbial Fuel Cell: Evidence of Long Distance Extracellular Electron Transport to ElectrodesClare E. Reimers0Cheng Li1Michael F. Graw2Paul S. Schrader3Michael Wolf4College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR, United StatesCollege of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR, United StatesCollege of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR, United StatesCollege of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR, United StatesTeledyne Benthos, North Falmouth, MA, United StatesMulticellular, filamentous, sulfur-oxidizing bacteria, known as cable bacteria, were discovered attached to fibers of a carbon brush electrode serving as an anode of a benthic microbial fuel cell (BMFC). The BMFC had been operated in a temperate estuarine environment for over a year before collecting anode samples for scanning electron microscopy and phylogenetic analyses. Individual filaments were attached by single terminus cells with networks of pilus-like nano-filaments radiating out from these cells, across the anode fiber surface, and between adjacent attachment locations. Current harvesting by the BMFC poised the anode at potentials of ~170–250 mV vs. SHE, and these surface potentials appear to have allowed the cable bacteria to use the anode as an electron acceptor in a completely anaerobic environment. A combination of catalyzed reporter deposition fluorescent in situ hybridization (CARD-FISH) and 16S rRNA gene sequence analysis confirmed the phylogeny of the cable bacteria and showed that filaments often occurred in bundles and in close association with members of the genera Desulfuromonas. However, the Desulfobulbaceae Operational Taxonomic Units (OTUs) from the 16S sequencing did not cluster closely with other putative cable bacteria sequences suggesting that the taxonomic delineation of cable bacteria is far from complete.http://journal.frontiersin.org/article/10.3389/fmicb.2017.02055/fullcable bacteriamicrobial fuel cellsulfur oxidationfilamentspiliextracellular electron transfer |
| spellingShingle | Clare E. Reimers Cheng Li Michael F. Graw Paul S. Schrader Michael Wolf The Identification of Cable Bacteria Attached to the Anode of a Benthic Microbial Fuel Cell: Evidence of Long Distance Extracellular Electron Transport to Electrodes Frontiers in Microbiology cable bacteria microbial fuel cell sulfur oxidation filaments pili extracellular electron transfer |
| title | The Identification of Cable Bacteria Attached to the Anode of a Benthic Microbial Fuel Cell: Evidence of Long Distance Extracellular Electron Transport to Electrodes |
| title_full | The Identification of Cable Bacteria Attached to the Anode of a Benthic Microbial Fuel Cell: Evidence of Long Distance Extracellular Electron Transport to Electrodes |
| title_fullStr | The Identification of Cable Bacteria Attached to the Anode of a Benthic Microbial Fuel Cell: Evidence of Long Distance Extracellular Electron Transport to Electrodes |
| title_full_unstemmed | The Identification of Cable Bacteria Attached to the Anode of a Benthic Microbial Fuel Cell: Evidence of Long Distance Extracellular Electron Transport to Electrodes |
| title_short | The Identification of Cable Bacteria Attached to the Anode of a Benthic Microbial Fuel Cell: Evidence of Long Distance Extracellular Electron Transport to Electrodes |
| title_sort | identification of cable bacteria attached to the anode of a benthic microbial fuel cell evidence of long distance extracellular electron transport to electrodes |
| topic | cable bacteria microbial fuel cell sulfur oxidation filaments pili extracellular electron transfer |
| url | http://journal.frontiersin.org/article/10.3389/fmicb.2017.02055/full |
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