Clifford Nkemnaso Obi^*, Grace Chigozirim Asogwa

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Department of Microbiology, College of Natural Sciences, Michael Okpara University of Agriculture, Umudike, Nigeria.
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Abstract: Electromicrobiology is the study of the interactions between the novel electrical properties of microorganisms and electronic devices. A diversity of microorganisms such as Geobacter and Shewanella species is capable of interacting electrically with the environment. Many recent advances in Electromicrobiology stem from studying Microbial Fuel Cells (MFCs) which are a device designed for the harvesting of electric current from organic compounds. Three types of Microbial Fuel Cells are known which are heterotrophic microbial fuel cells, photosynthetic microbial fuel cells (bio-solar cells) designed to harness the most abundant and promising energy source (solar irradiation) of earth and the hybrid microbial fuel cell. Electric microorganisms especially Sporomusa ovata can use electron derived from electrodes to reduce carbondioxide to multicarbon extracellular organic compounds in a process known as Microbial Electrosynthesis. The mechanism of electron transfer to electrodes by electric microbes is either by the use of electron shuttling molecules, redox-active proteins or via conductive pili. Conductive microorganisms and/or their nanowires have a number of potential practical applications but additional basic research will be necessary for rational applications. This review looks at the Microbial Fuel Cells, the associated mechanisms and applications.

Keywords: Electricity, Electrons, Microbes, Microbial Fuel Cells

Cite this paper: Obi, C. and Asogwa, G. (2015) Electromicrobiology: An Emerging Reality—A Review. Open Access Library Journal, 2, 1-10. doi: 10.4236/oalib.1102088.

References

[1]   Franks, A.E. and Nevin, K.P. (2010) Microbial Fuel Cells: A Current Review. Energies, 3, 899-919.

[2]   Malvankar, N.S., Mester, T., Tuominen, M. and Lovley, D.R. (2012) Supercapacitors Based on c-Type Cytochromes Using Conductive Nanostructured Networks of Living Bacteria. A European Journal of Chemical Physics and Physical Chemistry, 13, 463-468.
http://dx.doi.org/10.1002/cphc.201100865

[3]   Malvankar, N.S., Vargas, M., Nevin, K.P., Franks, A.E. and Leang, C. (2011) Tunable Metallic-Like Conductivity in Nanostructured Biofilms Comprised of Microbial Nanowires. Nature Nanotechnology, 6, 573-579.
http://dx.doi.org/10.1038/nnano.2011.119

[4]   Lovley, D.R. (2006) Bug Juice: Harvesting Electricity with Microorganisms. Nature Reviews Microbiology, 4, 497-508.
http://dx.doi.org/10.1038/nrmicro1442

[5]   Lovley, D.R. and Nevin, K.P. (2011) A Shift in the Current: New Applications and Concepts for Microbe-Electrode Electron Exchange. Current Opinion in Biotechnology, 22, 441.
http://dx.doi.org/10.1016/j.copbio.2011.01.009

[6]   Zhang, T., Gannon, S.M., Nevin, K.P., Franks, A.E. and Lovley, D.R. (2010) Stimulating the Anaerobic Degradation of Aromatic Hydrocarbons in Contaminated Sediments by Providing an Electrode as the Electron Acceptor. Environmental Microbiology, 12, 1011-1020.
http://dx.doi.org/10.1111/j.1462-2920.2009.02145.x

[7]   Bradley, R.W., Bombelli, P., Rowden, S. and Howe, C.J. (2012) Biological Photovoltaics: Intra- and Extra-Cellular Electron Transport by Cyanobacteria. Biochemical Society Transactions, 40, 1302-1307.
http://dx.doi.org/10.1042/BST20120118

[8]   Gregory, K.B., Bond, D.R. and Lovley, D.R. (2004) Graphite Electrodes as Electron Donors for Anaerobic Respiration. Environmental Microbiology, 6, 596.
http://dx.doi.org/10.1111/j.1462-2920.2004.00593.x

[9]   Steinbusch, K.J.J., Hamelers, H.V.M., Schaap, J.D., Kampman, C. and Buisman, C.J.N. (2010) A Kinetic Perspective on Extracellular Electron Transfer by Anode-Respiring Bacteria. FEMS Microbiology Reviews, 34, 3-17.
http://dx.doi.org/10.1111/j.1574-6976.2009.00191.x

[10]   McInerney, M.J., Sieber, J.R. and Gunsalus, R.P. (2009) Syntrophy in Anaerobic Global Carbon Cycles. Current Opinion in Biotechnology, 20, 623-634.
http://dx.doi.org/10.1016/j.copbio.2009.10.001

[11]   Morita, M., Malvankar, N.S., Franks, A.E., Summers, Z.M., Giloteaux, L., Rotaru, A.E., Rotaru, C. and Lovley, D.R. (2011) Potential for Direct Interspecies Electron Transfer in Methanogenic Wastewater Digester Aggregates. mBio, 2, e00159-11.
http://dx.doi.org/10.1128/mBio.00159-11

[12]   Lovley, D.R. and Phillips, E.J.P. (1988) Novel Mode of Microbial Energy Metabolism: Organic Carbon Oxidation Coupled to Dissimilatory Reduction of Iron or Manganese. Applied and Environmental Microbiology, 54, 1472-1480.

[13]   Nevin, K.P. and Lovley, D.R. (2000) Lack of Production of Electron-Shuttling Compounds or Solubilization of Fe(III) during Reduction of Insoluble Fe(III) Oxide by Geobacter metallireducens. Applied and Environmental Microbiology, 66, 2248-2251.
http://dx.doi.org/10.1128/AEM.66.5.2248-2251.2000

[14]   Reguera, G., Nevin, K.P., Nicoll, J.S., Covalla, S.F., Woodard, T.L. and Lovley, D.R. (2006) Biofilm and Nanowire Production Leads to Increased Current in Geobacter sulfurreducens Fuel Cells. Applied and Environmental Microbiology, 72, 7345-7348.
http://dx.doi.org/10.1128/AEM.01444-06

[15]   Bond, D.R., Holmes, D.E., Tender, L.M. and Lovley, D.R. (2002) Electrode-Reducing Microorganisms That Harvest Energy from Marine Sediments. Science, 295, 483-485.
http://dx.doi.org/10.1126/science.1066771

[16]   Nevin, K.P., Richter, H., Covalla, S.F., Johnson, J.P. and Woodard, T.L. (2008) Power Output and Columbic Efficiencies from Biofilms of Geobactersulfurreducens Comparable to Mixed Community Microbial Fuel Cells. Environmental Microbiology, 10, 2505-2514.
http://dx.doi.org/10.1111/j.1462-2920.2008.01675.x

[17]   Lovley, D.R. (2012) Electromicrobiology. Annual Review of Microbiology, 66, 391-409.
http://dx.doi.org/10.1146/annurev-micro-092611-150104

[18]   Rosenbaum, M. and Angenent, L.T. (2010) Cathodes as Electron Donors for Microbial Metabolism: Which Extracellular Electron Transfer Mechanism Are Involved? Current Opinion in Biotechnology, 21, 259-264.
http://dx.doi.org/10.1016/j.copbio.2010.03.010

[19]   Logan, B.E., Hamelers, B., Rozendal, R., Schroder, U., Keller, J., Freguia, S., Aelterman, P., Verstraete, W. and Rabaey, K. (2006) Microbial Fuel Cells: Methodology and Technology. Environmental Science & Technology, 17, 5181-5192.
http://dx.doi.org/10.1021/es0605016

[20]   Rabaey, K. and Verstraete, W. (2005) Microbial Electrosynthesis: Revisiting the Electrical Route for Microbial Production. Nature Reviews Microbiology, 8, 706-716.
http://dx.doi.org/10.1038/nrmicro2422

[21]   Borole, A.P., Reguera, G., Ringeisen, B., Wang, Z., Feng, Y. and Kim, B.H. (2011) Electroactive Biofilms: Current Status and Future Research Needs. Energy & Environmental Science, 4, 4813-4834.
http://dx.doi.org/10.1039/c1ee02511b

[22]   Strik, D., Timmers, R.A., Helder, M., Steinbusch, K., Hamelers, H. and Buisman, C.J.N. (2011) Microbial Solar Cells: Applying Photosynthetic and Electrochemically Active Organisms. Trends in Biotechnology, 29, 41-49.
http://dx.doi.org/10.1016/j.tibtech.2010.10.001

[23]   Nevin, K.P., Woodard, T.L., Franks, A.E., Summers, Z.M. and Lovley, D.R. (2010) Microbial Electrosynthesis: Feeding Microbes Electricity to Convert Carbon Dioxide and Water to Multicarbon Extracellular Organic Compounds. mBio, 1, e00103-10.
http://dx.doi.org/10.1128/mbio.00103-10

[24]   Lewis, N.S. and Nocera, D.G. (2006) Powering the Planet: Chemical Challenges in Solar Energy Utilization. Proceedings of the National Academy of Sciences of the United States of America, 103, 15729-15735.
http://dx.doi.org/10.1073/pnas.0603395103

[25]   Lovley, D.R. (2010) Powering Microbes with Electricity: Direct Electron Transfer from Electrodes to Microbes. Environmental Microbiology, 10, 1758-2229.

[26]   Strycharz, S.M. (2010) Reductive Dechlorination of 2-Chlorophenol by Anaeromyxobacter dehalogens with an Electrode Serving as the Electron Donor. Environmental Microbiology Reports, 2, 289-294.
http://dx.doi.org/10.1111/j.1758-2229.2009.00118.x

[27]   Cheng, S., Xing, D., Call, D.F. and Logan, B.E. (2009) Direct Biological Conversion of Electrical Current into Methane by Electromethanogenesis. Environmental Science & Technology, 43, 3953-3958.
http://dx.doi.org/10.1021/es803531g

[28]   Lovley, D.R. (2008) The Microbe Electric: Conversion of Organic Matter to Electricity. Current Opinion in Biotechnology, 19, 564-571.
http://dx.doi.org/10.1016/j.copbio.2008.10.005

[29]   Lovley, D.R., Ueki, T., Zhang, T., Malvankar, N.S. and Shrestha, P.M. (2011) Geobacter: The Microbe Electric’s Physiology, Ecology, and Practical Applications. Advances in Microbial Physiology, 59, 1-100.
http://dx.doi.org/10.1016/B978-0-12-387661-4.00004-5

[30]   Reguera, G., McCarthy, K.D., Mehta, T., Nicoll, J.S. and Tuominen, M.T. (2005) Extracellular Electron Transfer via Microbial Nanowires. Nature, 435, 1098-1101.
http://dx.doi.org/10.1038/nature03661

[31]   Leropoulos, I., Greenman, J. and Melhuish, C. (2010) Improved Energy Output Levels from Small-Scale Microbial Fuel Cells. Bioelectrochemistry, 78, 44-50.
http://dx.doi.org/10.1016/j.bioelechem.2009.05.009