@article {579,
	title = {Rapid evolution of redox processes in a petroleum hydrocarbon-contaminated aquifer.},
	journal = {Ground Water},
	volume = {40},
	year = {2002},
	month = {2002 Jul-Aug},
	pages = {353-60},
	abstract = {Ground water chemistry data collected over a six-year period show that the distribution of contaminants and redox processes in a shallow petroleum hydrocarbon-contaminated aquifer has changed rapidly over time. Shortly after a gasoline release occurred in 1990, high concentrations of benzene were present near the contaminant source area. In this contaminated zone, dissolved oxygen in ground water was depleted, and by 1994 Fe(III) reduction and sulfate reduction were the predominant terminal electron accepting processes. Significantly, dissolved methane was below measurable levels in 1994, indicating the absence of significant methanogenesis. By 1996, however, depletion of solid-phase Fe(III)-oxyhydrox ides in aquifer sediments and depletion of dissolved sulfate in ground water resulted in the onset of methanogenesis. Between 1996 and 2000, water-chemistry data indicated that methanogenic metabolism became increasingly prevalent. Molecular analysis of 16S-rDNA extracted from sediments shows the presence of a more diverse methanogenic community inside as opposed to outside the plume core, and is consistent with water-chemistry data indicating a shift toward methanogenesis over time. This rapid evolution of redox processes reflects several factors including the large amounts of contaminants, relatively rapid ground water flow (approximately 0.3 m/day [approximately foot/day]), and low concentrations of microbially reducible Fe(III) oxyhydroxides ( approximately 1 micromol/g) initially present in aquifer sediments. These results illustrate that, under certain hydrologic conditions, redox conditions in petroleum hydrocarbon-contaminated aquifers can change rapidly in time and space, and that the availability of solid-phase Fe(III)-oxyhydroxides affects this rate of change.},
	keywords = {Hydrocarbons, Iron, Methane, Oxidation-Reduction, Petroleum, Soil Pollutants, Solubility, Sulfates, Water Pollutants, Water Supply},
	issn = {0017-467X},
	author = {Chapelle, Francis H and Bradley, Paul M and Lovley, Derek R and O{\textquoteright}Neill, Kathleen and Landmeyer, James E}
}
@article {601,
	title = {Geobacter hydrogenophilus, Geobacter chapellei and Geobacter grbiciae, three new, strictly anaerobic, dissimilatory Fe(III)-reducers.},
	journal = {Int J Syst Evol Microbiol},
	volume = {51},
	year = {2001},
	month = {2001 Mar},
	pages = {581-8},
	abstract = {Recent studies on the diversity and ubiquity of Fe(III)-reducing organisms in different environments led to the isolation and identification of four new dissimilatory Fe(III)-reducers (strains H-2T, 172T, TACP-2T and TACP-5). All four isolates are non-motile, Gram-negative, freshwater, mesophilic, strict anaerobes with morphology identical to that of Geobacter metallireducens strain GS-15T. Analysis of the 16S rRNA sequences indicated that the new isolates belong to the genus Geobacter, in the delta-Proteobacteria. Significant differences in phenotypic characteristics, DNA-DNA homology and G+C content indicated that the four isolates represent three new species of the genus. The names Geobacter hydrogenophilus sp. nov. (strain H-2T), Geobacter chapellei sp. nov. (strain 172T) and Geobacter grbiciae sp. nov. (strains TACP-2T and TACP-5) are proposed. Geobacter hydrogenophilus and Geobacter chapellei were isolated from a petroleum-contaminated aquifer and a pristine, deep, subsurface aquifer, respectively. Geobacter grbiciae was isolated from aquatic sediments. All of the isolates can obtain energy for growth by coupling the oxidation of acetate to the reduction of Fe(III). The four isolates also coupled Fe(III) reduction to the oxidation of other simple, volatile fatty acids. In addition, Geobacter hydrogenophilus and Geobacter grbiciae were able to oxidize aromatic compounds such as benzoate, whilst Geobacter grbiciae was also able to use the monoaromatic hydrocarbon toluene.},
	keywords = {Base Composition, Deltaproteobacteria, Ferric Compounds, Gram-Negative Anaerobic Straight, Curved, and Helical Rods, Hydrocarbons, Iron, Molecular Sequence Data, Nucleic Acid Hybridization, Oxidation-Reduction, RNA, Ribosomal, 16S},
	issn = {1466-5026},
	author = {Coates, J D and Bhupathiraju, V K and Achenbach, L A and Mclnerney, M J and Lovley, D R}
}
@article {641,
	title = {Bioremediation of organic and metal contaminants with dissimilatory metal reduction.},
	journal = {J Ind Microbiol},
	volume = {14},
	year = {1995},
	month = {1995 Feb},
	pages = {85-93},
	abstract = {Dissimilatory metal reduction has the potential to be a helpful mechanism for both intrinsic and engineered bioremediation of contaminated environments. Dissimilatory Fe(III) reduction is an important intrinsic process for removing organic contaminants from aquifers contaminated with petroleum or landfill leachate. Stimulation of microbial Fe(III) reduction can enhance the degradation of organic contaminants in ground water. Dissimilatory reduction of uranium, selenium, chromium, technetium, and possibly other metals, can convert soluble metal species to insoluble forms that can readily be removed from contaminated waters or waste streams. Reduction of mercury can volatilize mercury from waters and soils. Despite its potential, there has as yet been limited applied research into the use of dissimilatory metal reduction as a bioremediation tool.},
	keywords = {Bacteria, Biodegradation, Environmental, Chromium, Hydrocarbons, Iron, Mercury, Metals, Oxidation-Reduction, Selenium, Uranium},
	issn = {0169-4146},
	author = {Lovley, D R}
}
@article {643,
	title = {Stimulated anoxic biodegradation of aromatic hydrocarbons using Fe(III) ligands.},
	journal = {Nature},
	volume = {370},
	year = {1994},
	month = {1994 Jul 14},
	pages = {128-31},
	abstract = {Contamination of ground waters with water-soluble aromatic hydrocarbons, common components of petroleum pollution, often produces anoxic conditions under which microbial degradation of the aromatics is slow. Oxygen is often added to contaminated ground water to stimulate biodegradation, but this can be technically difficult and expensive. Insoluble Fe(III) oxides, which are generally abundant in shallow aquifers, are alternative potential oxidants, but are difficult for microorganisms to access. Here we report that adding organic ligands that bind to Fe(III) dramatically increases its bioavailability, and that in the presence of these ligands, rates of degradation of aromatic hydrocarbons in anoxic aquifer sediments are comparable to those in oxic sediments. We find that even benzene, which is notoriously refractory in the absence of oxygen, can be rapidly degraded. Our results suggest that increasing the bioavailability of Fe(III) by adding suitable ligands provides a potential alternative to oxygen addition for the bioremediation of petroleum-contaminated aquifers.},
	keywords = {Benzene, Biodegradation, Environmental, Ferric Compounds, Hydrocarbons, Ligands, Methane, Nitrilotriacetic Acid, Oxidation-Reduction, Toluene, Water Pollutants, Chemical},
	issn = {0028-0836},
	doi = {10.1038/370128a0},
	author = {Lovley, D R and Woodward, J C and Chapelle, F H}
}
