Levar, Caleb2018-01-102018-01-102015-10https://hdl.handle.net/11299/192663University of Minnesota Ph.D. dissertation. October 2015. Major: Microbiology, Immunology and Cancer Biology. Advisor: Daniel Bond. 1 computer file (PDF); x, 148 pages.Geobacter sulfurreducens is a Gram negative δ-proteobacteria with the ability to couple the internal oxidation of a carbon and electron donor with the external reduction of extracellular electron acceptors. Extracellular electron acceptors utilized by G. sulfurreducens include insoluble Fe(III)- and Mn(IV)-oxides, electrodes poised at accepting potentials, and a variety of soluble acceptors including humic acids and chelated metals. These substrates exist over a redox potential window greater than 0.5 V, suggesting that respiratory flexibility to efficiently take advantage of electron acceptors with different redox potentials would be a useful trait. The data presented within this thesis demonstrate that G. sulfurreducens uses multiple electron transfer pathways for the reduction of extracellular electron acceptors of different redox potentials.enelectron transferGeobacteriron oxideredox potentialThesis or Dissertation