@article {482,
	title = {Sustained removal of uranium from contaminated groundwater following stimulation of dissimilatory metal reduction.},
	journal = {Environ Sci Technol},
	volume = {42},
	year = {2008},
	month = {2008 Apr 15},
	pages = {2999-3004},
	abstract = {Previous field studies on in situ bioremediation of uranium-contaminated groundwater in an aquifer in Rifle, Colorado identified two distinct phases following the addition of acetate to stimulate microbial respiration. In phase I, Geobacter species are the predominant organisms, Fe(III) is reduced, and microbial reduction of soluble U(VI) to insoluble U(IV) removes uranium from the groundwater. In phase II, Fe(III) is depleted, sulfate is reduced, and sulfate-reducing bacteria predominate. Long-term monitoring revealed an unexpected third phase during which U(VI) removal continues even after acetate additions are stopped. All three of these phases were successfully reproduced in flow-through sediment columns. When sediments from the third phase were heat sterilized, the capacity for U(VI) removal was lost. In the live sediments U(VI) removed from the groundwater was recovered as U(VI) in the sediments. This contrasts to the recovery of U(IV) in sediments resulting from the reduction of U(VI) to U(IV) during the Fe(III) reduction phase in acetate-amended sediments. Analysis of 16S rRNA gene sequences in the sediments in which U(VI) was being adsorbed indicated that members of the Firmicutes were the predominant organisms whereas no Firmicutes sequences were detected in background sediments which did not have the capacity to sorb U(VI), suggesting that the U(VI) adsorption might be due to the presence of these living organisms or at least their intact cell components. This unexpected enhanced adsorption of U(VI) onto sediments following the stimulation of microbial growth in the subsurface may potentially enhance the cost effectiveness of in situ uranium bioremediation.},
	keywords = {Acetates, Adsorption, Bacteria, Colorado, Geologic Sediments, Oxidation-Reduction, RNA, Ribosomal, 16S, Sulfates, Uranium, Water Pollutants, Radioactive, Water Supply},
	issn = {0013-936X},
	author = {N{\textquoteright}guessan, Lucie A and Vrionis, Helen A and Resch, Charles T and Long, Philip E and Lovley, Derek R}
}
@article {532,
	title = {Geobacter bemidjiensis sp. nov. and Geobacter psychrophilus sp. nov., two novel Fe(III)-reducing subsurface isolates.},
	journal = {Int J Syst Evol Microbiol},
	volume = {55},
	year = {2005},
	month = {2005 Jul},
	pages = {1667-74},
	abstract = {Fe(III)-reducing isolates were recovered from two aquifers in which Fe(III) reduction is known to be important. Strain Bem(T) was enriched from subsurface sediments collected in Bemidji, MN, USA, near a site where Fe(III) reduction is important in aromatic hydrocarbon degradation. Strains P11, P35(T) and P39 were isolated from the groundwater of an aquifer in Plymouth, MA, USA, in which Fe(III) reduction is important because of long-term inputs of acetate as a highway de-icing agent to the subsurface. All four isolates were Gram-negative, slightly curved rods that grew best in freshwater media. Strains P11, P35(T) and P39 exhibited motility via means of monotrichous flagella. Analysis of the 16S rRNA and nifD genes indicated that all four strains are delta-proteobacteria and members of the Geobacter cluster of the Geobacteraceae. Differences in phenotypic and phylogenetic characteristics indicated that the four isolates represent two novel species within the genus Geobacter. All of the isolates coupled the oxidation of acetate to the reduction of Fe(III) [iron(III) citrate, amorphous iron(III) oxide, iron(III) pyrophosphate and iron(III) nitrilotriacetate]. All four strains utilized ethanol, lactate, malate, pyruvate and succinate as electron donors and malate and fumarate as electron acceptors. Strain Bem(T) grew fastest at 30 degrees C, whereas strains P11, P35(T) and P39 grew equally well at 17, 22 and 30 degrees C. In addition, strains P11, P35(T) and P39 were capable of growth at 4 degrees C. The names Geobacter bemidjiensis sp. nov. (type strain Bem(T)=ATCC BAA-1014(T)=DSM 16622(T)=JCM 12645(T)) and Geobacter psychrophilus sp. nov. (strains P11, P35(T) and P39; type strain P35(T)=ATCC BAA-1013(T)=DSM 16674(T)=JCM 12644(T)) are proposed.},
	keywords = {Bacterial Proteins, Bacterial Typing Techniques, Cold Temperature, DNA, Bacterial, DNA, Ribosomal, Ferric Compounds, Fresh Water, Genes, rRNA, Geobacter, Geologic Sediments, Massachusetts, Minnesota, Molecular Sequence Data, Oxidation-Reduction, RNA, Ribosomal, 16S, Species Specificity, Water Supply},
	issn = {1466-5026},
	doi = {10.1099/ijs.0.63417-0},
	author = {Nevin, Kelly P and Holmes, Dawn E and Woodard, Trevor L and Hinlein, Erich S and Ostendorf, David W and Lovley, Derek R}
}
@article {560,
	title = {Diversity of Geobacteraceae species inhabiting metal-polluted freshwater lake sediments ascertained by 16S rDNA analyses.},
	journal = {Microb Ecol},
	volume = {46},
	year = {2003},
	month = {2003 Aug},
	pages = {257-69},
	abstract = {The abundance, distribution, and phylogenetic diversity of members of the Fe(III)-reducing family Geobacteraceae were studied along a gradient of metal contaminants in Lake Coeur d{\textquoteright}Alene, Idaho. Partial 16S rRNA gene fragments were amplified by PCR using primers directed toward conserved regions of the gene within the family Geobacteraceae. Analysis of amplicons separated by denaturing gradient gel electrophoresis (DGGE) suggested within-site variation was as great as between-site variation. Amplicons were cloned and grouped by RFLP type and DGGE migration distance and representatives were sequenced. Grouping clones with 3\% or less sequence dissimilarity, 15 distinct phylotypes were identified compared to 16 distinct DGGE bands. Only 1 phylotype was recovered from all sites. This clone, B14, is most closely related to Geobacter metallireducens and constituted a greater portion of the pristine community than of the contaminated communities. A second phylotype, Q2, predominated in the contaminated communities and was notably absent from the pristine libraries. Clone Q2 presents a high degree of sequence similarity to two Geobacter spp. previously isolated from this region of Lake Coeur d{\textquoteright}Alene. Six phylotypes were unique to the contaminated sediments, whereas two were found only in the pristine sediments. Indices of diversity (Shannon and Simpson) were consistently higher when calculated with DGGE data than when clone library data were used. Most-probable-number PCR and real-time PCR suggested that the Geobacteraceae phylotypes were spread relatively evenly across all three sites along the gradient. Our data indicate that the Geobacteraceae are diverse and abundant in Lake Coeur d{\textquoteright}Alene sediments, regardless of metals content. These results provide insight into the ability of dissimilatory Fe(III)-reducing bacteria to colonize habitats with elevated metal concentrations, and they have important implications for the management and remediation of metal-contaminated sites.},
	keywords = {Cloning, Molecular, Geobacter, Geologic Sediments, Phylogeny, Polymerase Chain Reaction, Population Dynamics, RNA, Ribosomal, 16S, Water Pollutants, Water Supply},
	issn = {0095-3628},
	author = {Cummings, D E and Snoeyenbos-West, O L and Newby, D T and Niggemyer, A M and Lovley, D R and Achenbach, L A and Rosenzweig, R F}
}
@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 {616,
	title = {Geothrix fermentans gen. nov., sp. nov., a novel Fe(III)-reducing bacterium from a hydrocarbon-contaminated aquifer.},
	journal = {Int J Syst Bacteriol},
	volume = {49 Pt 4},
	year = {1999},
	month = {1999 Oct},
	pages = {1615-22},
	abstract = {In an attempt to understand better the micro-organisms involved in anaerobic degradation of aromatic hydrocarbons in the Fe(III)-reducing zone of petroleum-contaminated aquifers, Fe(III)-reducing micro-organisms were isolated from contaminated aquifer material that had been adapted for rapid oxidation of toluene coupled to Fe(III) reduction. One of these organisms, strain H-5T, was enriched and isolated on acetate/Fe(III) medium. Strain H-5T is a Gram-negative strict anaerobe that grows with various simple organic acids such as acetate, propionate, lactate and fumarate as alternative electron donors with Fe(III) as the electron acceptor. In addition, strain H-5T also oxidizes long-chain fatty acids such as palmitate with Fe(III) as the sole electron acceptor. Strain H-5T can also grow by fermentation of citrate or fumarate in the absence of an alternative electron acceptor. The primary end-products of citrate fermentation are acetate and succinate. In addition to various forms of soluble and insoluble Fe(III), strain H-5T grows with nitrate, Mn(IV), fumarate and the humic acid analogue 2,6-anthraquinone disulfonate as alternative electron acceptors. As with other organisms that can oxidize organic compounds completely with the reduction of Fe(III), cell suspensions of strain H-5T have absorbance maxima indicative of a c-type cytochrome(s). It is proposed that strain H-5T represents a novel genus in the Holophaga-Acidobacterium phylum and that it should be named Geothrix fermentans sp. nov., gen. nov.},
	keywords = {Biodegradation, Environmental, DNA, Bacterial, DNA, Ribosomal, Ferric Compounds, Geologic Sediments, Gram-Negative Anaerobic Bacteria, Molecular Sequence Data, Oxidation-Reduction, Petroleum, Phylogeny, RNA, Ribosomal, 16S, Water Microbiology, Water Pollutants, Chemical, Water Supply},
	issn = {0020-7713},
	author = {Coates, J D and Ellis, D J and Gaw, C V and Lovley, D R}
}
