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.
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
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
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 Anaeromyxobacterdehalogens 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
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
