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Electricity Production By Geobacter Sulfurreducens Attached To Electrodes, Daniel R. Bond, Derek Lovley
Electricity Production By Geobacter Sulfurreducens Attached To Electrodes, Daniel R. Bond, Derek Lovley
Derek Lovley
Previous studies have suggested that members of the Geobacteraceae can use electrodes as electron acceptors for anaerobic respiration. In order to better understand this electron transfer process for energy production, Geobacter sulfurreducens was inoculated into chambers in which a graphite electrode served as the sole electron acceptor and acetate or hydrogen was the electron donor. The electron-accepting electrodes were maintained at oxidizing potentials by connecting them to similar electrodes in oxygenated medium (fuel cells) or to potentiostats that poised electrodes at +0.2 V versus an Ag/AgCl reference electrode (poised potential). When a small inoculum of G. sulfurreducens was introduced into …
Enrichment Of Members Of The Family Geobacteraceae Associated With Stimulation Of Dissimilatory Metal Reduction In Uranium-Contaminated Aquifer Sediments, Dawn E. Holmes, Kevin T. Finneran, Regina A. O'Neil, Derek Lovley
Enrichment Of Members Of The Family Geobacteraceae Associated With Stimulation Of Dissimilatory Metal Reduction In Uranium-Contaminated Aquifer Sediments, Dawn E. Holmes, Kevin T. Finneran, Regina A. O'Neil, Derek Lovley
Derek Lovley
Stimulating microbial reduction of soluble U(VI) to insoluble U(IV) shows promise as a strategy for immobilizing uranium in uranium-contaminated subsurface environments. In order to learn more about which microorganisms might be involved in U(VI) reduction in situ, the changes in the microbial community when U(VI) reduction was stimulated with the addition of acetate were monitored in sediments from three different uranium-contaminated sites in the floodplain of the San Juan River in Shiprock, N.Mex. In all three sediments U(VI) reduction was accompanied by concurrent Fe(III) reduction and a dramatic enrichment of microorganisms in the family Geobacteraceae, which are known U(VI)- and …
Mechanisms For Accessing Insoluble Fe(Iii) Oxide During Dissimilatory Fe(Iii) Reduction By Geothrix Fermentans, Kelly P. Nevin, Derek Lovley
Mechanisms For Accessing Insoluble Fe(Iii) Oxide During Dissimilatory Fe(Iii) Reduction By Geothrix Fermentans, Kelly P. Nevin, Derek Lovley
Derek Lovley
Mechanisms for Fe(III) oxide reduction were investigated in Geothrix fermentans, a dissimilatory Fe(III)-reducing microorganism found within the Fe(III) reduction zone of subsurface environments. Culture filtrates of G. fermentans stimulated the reduction of poorly crystalline Fe(III) oxide by washed cell suspensions, suggesting that G. fermentans released one or more extracellular compounds that promoted Fe(III) oxide reduction. In order to determine if G. fermentans released electron-shuttling compounds, poorly crystalline Fe(III) oxide was incorporated into microporous alginate beads, which prevented contact between G. fermentans and the Fe(III) oxide. G. fermentans reduced the Fe(III) within the beads, suggesting that one of the compounds that …
Use Of Fe(Iii) As An Electron Acceptor To Recover Previously Uncultured Hyperthermophilesl Isolation And Characterization Of Geothermobacterium Ferrireducens Gen.Nov., Sp. Nov., Kazem Kashefi, Dawn E. Holmes, Anna-Louise Reysenbach, Derek Lovley
Use Of Fe(Iii) As An Electron Acceptor To Recover Previously Uncultured Hyperthermophilesl Isolation And Characterization Of Geothermobacterium Ferrireducens Gen.Nov., Sp. Nov., Kazem Kashefi, Dawn E. Holmes, Anna-Louise Reysenbach, Derek Lovley
Derek Lovley
It has recently been recognized that the ability to use Fe(III) as a terminal electron acceptor is a highly conserved characteristic in hyperthermophilic microorganisms. This suggests that it may be possible to recover as-yet-uncultured hyperthermophiles in pure culture if Fe(III) is used as an electron acceptor. As part of a study of the microbial diversity of the Obsidian Pool area in Yellowstone National Park, Wyo., hot sediment samples were used as the inoculum for enrichment cultures in media containing hydrogen as the sole electron donor and poorly crystalline Fe(III) oxide as the electron acceptor. A pure culture was recovered on …
Analysis Of The Genetic Potential And Gene Expression Of Microbial Communities Involved In The In Situ Bioremediation Of Uranium And Harvesting Electrical Energy From Organic Matter, Derek Lovley
Derek Lovley
The goal of this genomes-to-life project is to develop models that can describe the functioning of the microbial communities involved in the in situ bioremediation of uranium-contaminated groundwater and harvesting electricity from waste organic matter. Previous studies have demonstrated that the microbial communities involved in uranium bioremediation and energy harvesting are both dominated by microorganisms in the family Geobacteraceae and that these Geobacteraceae are responsible for the uranium bioremediation and electron transfer to electrodes. The research plan is diagrammed below. Examples of how both pure culture and environmental genomic studies have dramatically changed the concepts of how Geobacteraceae-dominated subsurface communities …