@article {460,
	title = {Selection of a variant of Geobacter sulfurreducens with enhanced capacity for current production in microbial fuel cells.},
	journal = {Biosens Bioelectron},
	volume = {24},
	year = {2009},
	month = {2009 Aug 15},
	pages = {3498-503},
	abstract = {Geobacter sulfurreducens produces current densities in microbial fuel cells that are among the highest known for pure cultures. The possibility of adapting this organism to produce even higher current densities was evaluated. A system in which a graphite anode was poised at -400 mV (versus Ag/AgCl) was inoculated with the wild-type strain of G. sulfurreducens, strain DL-1. An isolate, designated strain KN400, was recovered from the biofilm after 5 months of growth on the electrode. KN400 was much more effective in current production than strain DL-1. This was apparent with anodes poised at -400 mV, as well as in systems run in true fuel cell mode. KN400 had current (7.6A/m(2)) and power (3.9 W/m(2)) densities that respectively were substantially higher than those of DL1 (1.4A/m(2) and 0.5 W/m(2)). On a per cell basis KN400 was more effective in current production than DL1, requiring thinner biofilms to make equivalent current. The enhanced capacity for current production in KN400 was associated with a greater abundance of electrically conductive microbial nanowires than DL1 and lower internal resistance (0.015 versus 0.130 Omega/m(2)) and mass transfer limitation in KN400 fuel cells. KN400 produced flagella, whereas DL1 does not. Surprisingly, KN400 had much less outer-surface c-type cytochromes than DL1. KN400 also had a greater propensity to form biofilms on glass or graphite than DL1, even when growing with the soluble electron acceptor, fumarate. These results demonstrate that it is possible to enhance the ability of microorganisms to electrochemically interact with electrodes with the appropriate selective pressure and that improved current production is associated with clear differences in the properties of the outer surface of the cell that may provide insights into the mechanisms for microbe-electrode interactions.},
	keywords = {Bioelectric Energy Sources, Electrochemistry, Equipment Design, Equipment Failure Analysis, Geobacter, Species Specificity},
	issn = {1873-4235},
	doi = {10.1016/j.bios.2009.05.004},
	author = {Yi, Hana and Nevin, Kelly P and Kim, Byoung-Chan and Franks, Ashely E and Klimes, Anna and Tender, Leonard M and Lovley, Derek R}
}
@article {523,
	title = {Harvesting energy from the marine sediment-water interface II. Kinetic activity of anode materials.},
	journal = {Biosens Bioelectron},
	volume = {21},
	year = {2006},
	month = {2006 May 15},
	pages = {2058-63},
	abstract = {Here, we report a comparative study on the kinetic activity of various anodes of a recently described microbial fuel cell consisting of an anode imbedded in marine sediment and a cathode in overlying seawater. Using plain graphite anodes, it was demonstrated that a significant portion of the anodic current results from oxidation of sediment organic matter catalyzed by microorganisms colonizing the anode and capable of directly reducing the anode without added exogenous electron-transfer mediators. Here, graphite anodes incorporating microbial oxidants are evaluated in the laboratory relative to plain graphite with the goal of increasing power density by increasing current density. Anodes evaluated include graphite modified by adsorption of anthraquinone-1,6-disulfonic acid (AQDS) or 1,4-naphthoquinone (NQ), a graphite-ceramic composite containing Mn2+ and Ni2+, and graphite modified with a graphite paste containing Fe3O4 or Fe3O4 and Ni2+. It was found that these anodes possess between 1.5- and 2.2-fold greater kinetic activity than plain graphite. Fuel cells were deployed in a coastal site near Tuckerton, NJ (USA) that utilized two of these anodes. These fuel cells generated ca. 5-fold greater current density than a previously characterized fuel cell equipped with a plain graphite anode, and operated at the same site.},
	keywords = {Electrochemistry, Electrodes, Energy-Generating Resources, Ferumoxytol, Geologic Sediments, Kinetics, Oceans and Seas, Seawater},
	issn = {0956-5663},
	doi = {10.1016/j.bios.2006.01.033},
	author = {Lowy, Daniel A and Tender, Leonard M and Zeikus, J Gregory and Park, Doo Hyun and Lovley, Derek R}
}
