Introduction
By [Kyle Bailey]
Metal Respiration
Microbial Fuel Cell (MFC)
Figure 2. A diagram of a (microbial fuel cell) MFC containing a graphite anode that is serving as a final electron acceptor. The bacteria are performing anaerobic microbial oxidation on the various organic compounds present. In the middle of the anaerobic anode and aerobic cathode is a proton diffusion layer that separates them showing that water is formed at the cathode (Franks and Nevin., 2010).
Figure 3. In current producing biofilms bacterial cells conduct electron transfer using membrane bound cytochromes. The bacterial cells use a long range network capable of conducting electron flow from the farthest cells to the closest ones to the anode. Oxidation of the organic substrate leads to a high concentration of protons under the biofilm mass where it is highest towards the anode (Franks and Nevin., 2010).
Figure 4. SEM image of a graphite anode depicting G. fermentans growth in a (microbial fuel cell) MFC (Bond and Lovely,. 2005).
Conclusion
Overall text length at least 3,000 words, with at least 3 figures.
References
1. Coates, John D., Debra J. Ellis, Catherine V Gaw, and Derek R. Lovley. "Geothrix ferrnentans gen. nov., sp. nov., a novel Fe(l1l)-reducing bacterium from a hydrocarbon-contaminated aquifer." international Journal of Systematic Bacteriology. 49 (1999): 161 5-1 622.
2. Franks, Ashley E., and Kelly P. Nevin. "Microbial Fuel Cells, A Current Review." Energies. 3 (2010): 899-919.
3. Bond, Daniel R., and Derek R. Lovley. "Evidence for Involvement of an Electron Shuttle in Electricity Generation by Geothrix fermentans." APPLIED AND ENVIRONMENTAL MICROBIOLOGY. (2005): p. 2186–2189.
4. Nevin, Kelly P., and Derek R. Lovley. "Mechanisms for Accessing Insoluble Fe(III) Oxide during Dissimilatory Fe(III) Reduction by Geothrix fermentans." APPLIED AND ENVIRONMENTAL MICROBIOLOGY. (2002): p. 2294–2299.
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6. [Slonczewski, Joan, and John W. Foster. Microbiology an evolving science. 2nd. ed. New York: W.W Norton & Company, Inc., 2010. 1-1100.]
7. [Kyrpides, Nikos (September 23, 2011). "Geothrix fermentans DSM 14018". Doe Joint Genome Institute. Retrieved October 26, 2012]
8. [Liu, Joanne K.; Mehta-Kolte, Misha; Bond, Daniel R. "Expression and purification of GxcA, a c-type cytochrome involved in metal respiration by the bacterium Geothrix fermentans". University of Minnesota. Retrieved October 25, 2012]
Edited by student of Joan Slonczewski for BIOL 238 Microbiology, 2011, Kenyon College.
