@article {3147,
	title = {Molecular analysis of the in situ growth rates of subsurface Geobacter species.},
	journal = {Appl Environ Microbiol},
	volume = {79},
	year = {2013},
	month = {2013 Mar},
	pages = {1646-53},
	abstract = {<p>Molecular tools that can provide an estimate of the in situ growth rate of Geobacter species could improve understanding of dissimilatory metal reduction in a diversity of environments. Whole-genome microarray analyses of a subsurface isolate of Geobacter uraniireducens, grown under a variety of conditions, identified a number of genes that are differentially expressed at different specific growth rates. Expression of two genes encoding ribosomal proteins, rpsC and rplL, was further evaluated with quantitative reverse transcription-PCR (qRT-PCR) in cells with doubling times ranging from 6.56 h to 89.28 h. Transcript abundance of rpsC correlated best (r(2) = 0.90) with specific growth rates. Therefore, expression patterns of rpsC were used to estimate specific growth rates of Geobacter species during an in situ uranium bioremediation field experiment in which acetate was added to the groundwater to promote dissimilatory metal reduction. Initially, increased availability of acetate in the groundwater resulted in higher expression of Geobacter rpsC, and the increase in the number of Geobacter cells estimated with fluorescent in situ hybridization compared well with specific growth rates estimated from levels of in situ rpsC expression. However, in later phases, cell number increases were substantially lower than predicted from rpsC transcript abundance. This change coincided with a bloom of protozoa and increased attachment of Geobacter species to solid phases. These results suggest that monitoring rpsC expression may better reflect the actual rate that Geobacter species are metabolizing and growing during in situ uranium bioremediation than changes in cell abundance.</p>},
	keywords = {Acetates, Biodegradation, Environmental, DNA, Bacterial, Gene Expression Profiling, Geobacter, Groundwater, In Situ Hybridization, Fluorescence, Molecular Sequence Data, Ribosomal Proteins, Sequence Analysis, DNA, Uranium},
	issn = {1098-5336},
	doi = {10.1128/AEM.03263-12},
	author = {Holmes, Dawn E and Giloteaux, Ludovic and Barlett, Melissa and Chavan, Milind A and Smith, Jessica A and Williams, Kenneth H and Wilkins, Michael and Long, Philip and Lovley, Derek R}
}
@article {471,
	title = {Transcriptome of Geobacter uraniireducens growing in uranium-contaminated subsurface sediments.},
	journal = {ISME J},
	volume = {3},
	year = {2009},
	month = {2009 Feb},
	pages = {216-30},
	abstract = {To learn more about the physiological state of Geobacter species living in subsurface sediments, heat-sterilized sediments from a uranium-contaminated aquifer in Rifle, Colorado, were inoculated with Geobacter uraniireducens, a pure culture representative of the Geobacter species that predominates during in situ uranium bioremediation at this site. Whole-genome microarray analysis comparing sediment-grown G. uraniireducens with cells grown in defined culture medium indicated that there were 1084 genes that had higher transcript levels during growth in sediments. Thirty-four c-type cytochrome genes were upregulated in the sediment-grown cells, including several genes that are homologous to cytochromes that are required for optimal Fe(III) and U(VI) reduction by G. sulfurreducens. Sediment-grown cells also had higher levels of transcripts, indicative of such physiological states as nitrogen limitation, phosphate limitation and heavy metal stress. Quantitative reverse transcription PCR showed that many of the metabolic indicator genes that appeared to be upregulated in sediment-grown G. uraniireducens also showed an increase in expression in the natural community of Geobacter species present during an in situ uranium bioremediation field experiment at the Rifle site. These results demonstrate that it is feasible to monitor gene expression of a microorganism growing in sediments on a genome scale and that analysis of the physiological status of a pure culture growing in subsurface sediments can provide insights into the factors controlling the physiology of natural subsurface communities.},
	keywords = {Colorado, DNA, Bacterial, Environmental Microbiology, Gene Expression Profiling, Geobacter, Geologic Sediments, Molecular Sequence Data, Oligonucleotide Array Sequence Analysis, Sequence Analysis, DNA, Uranium},
	issn = {1751-7370},
	doi = {10.1038/ismej.2008.89},
	author = {Holmes, Dawn E and O{\textquoteright}Neil, Regina A and Chavan, Milind A and N{\textquoteright}guessan, Lucie A and Vrionis, Helen A and Perpetua, Lorrie A and Larrahondo, M Juliana and DiDonato, Raymond and Liu, Anna and Lovley, Derek R}
}
@article {508,
	title = {Geobacter pickeringii sp. nov., Geobacter argillaceus sp. nov. and Pelosinus fermentans gen. nov., sp. nov., isolated from subsurface kaolin lenses.},
	journal = {Int J Syst Evol Microbiol},
	volume = {57},
	year = {2007},
	month = {2007 Jan},
	pages = {126-35},
	abstract = {The goal of this project was to isolate representative Fe(III)-reducing bacteria from kaolin clays that may influence iron mineralogy in kaolin. Two novel dissimilatory Fe(III)-reducing bacteria, strains G12(T) and G13(T), were isolated from sedimentary kaolin strata in Georgia (USA). Cells of strains G12(T) and G13(T) were motile, non-spore-forming regular rods, 1-2 mum long and 0.6 mum in diameter. Cells had one lateral flagellum. Phylogenetic analyses using the 16S rRNA gene sequence of the novel strains demonstrated their affiliation to the genus Geobacter. Strain G12(T) was most closely related to Geobacter pelophilus (94.7 \%) and Geobacter chapellei (94.1 \%). Strain G13(T) was most closely related to Geobacter grbiciae (95.3 \%) and Geobacter metallireducens (95.1 \%). Based on phylogenetic analyses and phenotypic differences between the novel isolates and other closely related species of the genus Geobacter, the isolates are proposed as representing two novel species, Geobacter argillaceus sp. nov. (type strain G12(T)=ATCC BAA-1139(T)=JCM 12999(T)) and Geobacter pickeringii sp. nov. (type strain G13(T)=ATCC BAA-1140(T)=DSM 17153(T)=JCM 13000(T)). Another isolate, strain R7(T), was derived from a primary kaolin deposit in Russia. The cells of strain R7(T) were motile, spore-forming, slightly curved rods, 0.6 x 2.0-6.0 microm in size and with up to six peritrichous flagella. Strain R7(T) was capable of reducing Fe(III) only in the presence of a fermentable substrate. 16S rRNA gene sequence analysis demonstrated that this isolate is unique, showing less than 92 \% similarity to bacteria of the Sporomusa-Pectinatus-Selenomomas phyletic group, including {\textquoteright}Anaerospora hongkongensis{\textquoteright} (90.2 \%), Acetonema longum (90.6 \%), Dendrosporobacter quercicolus (90.9 \%) and Anaerosinus glycerini (91.5 \%). On the basis of phylogenetic analysis and physiological tests, strain R7(T) is proposed to represent a novel genus and species, Pelosinus fermentans gen. nov., sp. nov. (type strain R7(T)=DSM 17108(T)=ATCC BAA-1133(T)), in the Sporomusa-Pectinatus-Selenomonas group.},
	keywords = {Bacterial Typing Techniques, Base Composition, DNA, Bacterial, DNA, Ribosomal, Ferric Compounds, Genes, rRNA, Geobacter, Geologic Sediments, Georgia, Kaolin, Molecular Sequence Data, Oxidation-Reduction, Phylogeny, RNA, Ribosomal, 16S, Russia, Sequence Analysis, DNA, Species Specificity},
	issn = {1466-5026},
	doi = {10.1099/ijs.0.64221-0},
	author = {Shelobolina, Evgenya S and Nevin, Kelly P and Blakeney-Hayward, Jessie D and Johnsen, Claudia V and Plaia, Todd W and Krader, Paul and Woodard, Trevor and Holmes, Dawn E and Vanpraagh, Catherine Gaw and Lovley, Derek R}
}
@article {493,
	title = {Subsurface clade of Geobacteraceae that predominates in a diversity of Fe(III)-reducing subsurface environments.},
	journal = {ISME J},
	volume = {1},
	year = {2007},
	month = {2007 Dec},
	pages = {663-77},
	abstract = {There are distinct differences in the physiology of Geobacter species available in pure culture. Therefore, to understand the ecology of Geobacter species in subsurface environments, it is important to know which species predominate. Clone libraries were assembled with 16S rRNA genes and transcripts amplified from three subsurface environments in which Geobacter species are known to be important members of the microbial community: (1) a uranium-contaminated aquifer located in Rifle, CO, USA undergoing in situ bioremediation; (2) an acetate-impacted aquifer that serves as an analog for the long-term acetate amendments proposed for in situ uranium bioremediation and (3) a petroleum-contaminated aquifer in which Geobacter species play a role in the oxidation of aromatic hydrocarbons coupled with the reduction of Fe(III). The majority of Geobacteraceae 16S rRNA sequences found in these environments clustered in a phylogenetically coherent subsurface clade, which also contains a number of Geobacter species isolated from subsurface environments. Concatamers constructed with 43 Geobacter genes amplified from these sites also clustered within this subsurface clade. 16S rRNA transcript and gene sequences in the sediments and groundwater at the Rifle site were highly similar, suggesting that sampling groundwater via monitoring wells can recover the most active Geobacter species. These results suggest that further study of Geobacter species in the subsurface clade is necessary to accurately model the behavior of Geobacter species during subsurface bioremediation of metal and organic contaminants.},
	keywords = {Biodegradation, Environmental, Ecosystem, Ferric Compounds, Geobacter, Hydrocarbons, Aromatic, Molecular Sequence Data, Oxidation-Reduction, Petroleum, Phylogeny, Polymerase Chain Reaction, RNA, Ribosomal, 16S, Sequence Analysis, DNA, Uranium},
	issn = {1751-7362},
	doi = {10.1038/ismej.2007.85},
	author = {Holmes, Dawn E and O{\textquoteright}Neil, Regina A and Vrionis, Helen A and N{\textquoteright}guessan, Lucie A and Ortiz-Bernad, Irene and Larrahondo, Maria J and Adams, Lorrie A and Ward, Joy A and Nicoll, Julie S and Nevin, Kelly P and Chavan, Milind A and Johnson, Jessica P and Long, Philip E and Lovley, Derek R}
}
@article {547,
	title = {Comparison of 16S rRNA, nifD, recA, gyrB, rpoB and fusA genes within the family Geobacteraceae fam. nov.},
	journal = {Int J Syst Evol Microbiol},
	volume = {54},
	year = {2004},
	month = {2004 Sep},
	pages = {1591-9},
	abstract = {The sequences of five conserved genes, in addition to the 16S rRNA gene, were investigated in 30 members of the Geobacteraceae fam. nov. All members of the Geobacteraceae examined contained nifD, suggesting that they are capable of nitrogen fixation, which may explain their ability to compete effectively in nitrogen-poor subsurface environments undergoing remediation for petroleum or metal contamination. The phylogenies predicted from rpoB, gyrB, fusA, recA and nifD were generally in agreement with the phylogeny predicted from 16S rRNA gene sequences. Furthermore, phylogenetic analysis of concatemers constructed from all five protein-coding genes corresponded closely with the 16S rRNA gene-based phylogeny. This study demonstrated that the Geobacteraceae is a phylogenetically coherent family within the delta-subclass of the Proteobacteria that is composed of three distinct phylogenetic clusters: Geobacter, Desulfuromonas and Desulfuromusa. The sequence data provided here will make it possible to discriminate better between physiologically distinct members of the Geobacteraceae, such as Pelobacter propionicus and Geobacter species, in geobacteraceae-dominated microbial communities and greatly expands the potential to identify geobacteraceae sequences in libraries of environmental genomic DNA.},
	keywords = {Bacterial Proteins, Deltaproteobacteria, Desulfuromonas, DNA Gyrase, DNA, Bacterial, DNA, Ribosomal, DNA-Directed RNA Polymerases, Genes, Bacterial, Genes, rRNA, Geobacter, Molecular Sequence Data, Nitrogen Fixation, Peptide Elongation Factor G, Phylogeny, Rec A Recombinases, RNA, Bacterial, RNA, Ribosomal, 16S, Sequence Analysis, DNA},
	issn = {1466-5026},
	doi = {10.1099/ijs.0.02958-0},
	author = {Holmes, Dawn E and Nevin, Kelly P and Lovley, Derek R}
}
@article {581,
	title = {Geoglobus ahangari gen. nov., sp. nov., a novel hyperthermophilic archaeon capable of oxidizing organic acids and growing autotrophically on hydrogen with Fe(III) serving as the sole electron acceptor.},
	journal = {Int J Syst Evol Microbiol},
	volume = {52},
	year = {2002},
	month = {2002 May},
	pages = {719-28},
	abstract = {A novel, regular to irregular, coccoid-shaped, anaerobic, Fe(III)-reducing microorganism was isolated from the Guaymas Basin hydrothermal system at a depth of 2000 m. Isolation was carried out with a new technique using Fe(III) oxide as the electron acceptor for the recovery of colonies on solid medium. The isolate, designated strain 234T, was strictly anaerobic and exhibited a tumbling motility. The cells had a single flagellum. Strain 234T grew at temperatures between 65 and 90 degrees C, with an optimum at about 88 degrees C. The optimal salt concentration for growth was around 19 g l(-1). The isolate was capable of growth with H2 as the sole electron donor coupled to the reduction of Fe(III) without the need for an organic carbon source. This is the first example of a dissimilatory Fe(III)-reducing micro-organism capable of growing autotrophically on hydrogen. In addition to molecular hydrogen, strain 234T oxidizes pyruvate, acetate, malate, succinate, peptone, formate, fumarate, yeast extract, glycerol, isoleucine, arginine, serine, glutamine, asparagine, stearate, palmitate, valerate, butyrate and propionate with the reduction of Fe(III). This isolate is the first example of a hyperthermophile capable of oxidizing long-chain fatty acids anaerobically. Isolate 234T grew exclusively with Fe(III) as the sole electron acceptor. The G+C content was 58.7 mol\%. Based on detailed analysis of its 16S rDNA sequence, G+C content, distinguishing physiological features and metabolism, strain 234T is proposed to represent a novel genus within the Archaeoglobales. The name proposed for strain 234T is Geoglobus ahangari gen. nov., sp. nov..},
	keywords = {Anaerobiosis, Archaea, Bacterial Typing Techniques, DNA, Ribosomal, Electron Transport, Fatty Acids, Ferric Compounds, Hot Temperature, Hydrogen, Molecular Sequence Data, Oxidation-Reduction, Phylogeny, RNA, Ribosomal, 16S, Sequence Analysis, DNA, Water Microbiology},
	issn = {1466-5026},
	author = {Kashefi, Kazem and Tor, Jason M and Holmes, Dawn E and Gaw Van Praagh, Catherine V and Reysenbach, Anna-Louise and Lovley, Derek R}
}
@article {587,
	title = {Use of Fe(III) as an electron acceptor to recover previously uncultured hyperthermophiles: isolation and characterization of Geothermobacterium ferrireducens gen. nov., sp. nov.},
	journal = {Appl Environ Microbiol},
	volume = {68},
	year = {2002},
	month = {2002 Apr},
	pages = {1735-42},
	abstract = {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 solidified, Fe(III) oxide medium. The isolate, designated FW-1a, is a hyperthermophilic anaerobe that grows exclusively by coupling hydrogen oxidation to the reduction of poorly crystalline Fe(III) oxide. Organic carbon is not required for growth. Magnetite is the end product of Fe(III) oxide reduction under the culture conditions evaluated. The cells are rod shaped, about 0.5 microm by 1.0 to 1.2 microm, and motile and have a single flagellum. Strain FW-1a grows at circumneutral pH, at freshwater salinities, and at temperatures of between 65 and 100 degrees C with an optimum of 85 to 90 degrees C. To our knowledge this is the highest temperature optimum of any organism in the Bacteria. Analysis of the 16S ribosomal DNA (rDNA) sequence of strain FW-1a places it within the Bacteria, most closely related to abundant but uncultured microorganisms whose 16S rDNA sequences have been previously recovered from Obsidian Pool and a terrestrial hot spring in Iceland. While previous studies inferred that the uncultured microorganisms with these 16S rDNA sequences were sulfate-reducing organisms, the physiology of the strain FW-1a, which does not reduce sulfate, indicates that these organisms are just as likely to be Fe(III) reducers. These results further demonstrate that Fe(III) may be helpful for recovering as-yet-uncultured microorganisms from hydrothermal environments and illustrate that caution must be used in inferring the physiological characteristics of at least some thermophilic microorganisms solely from 16S rDNA sequences. Based on both its 16S rDNA sequence and physiological characteristics, strain FW-1a represents a new genus among the Bacteria. The name Geothermobacterium ferrireducens gen. nov., sp. nov., is proposed (ATCC BAA-426).},
	keywords = {Bacterial Typing Techniques, Culture Media, DNA, Ribosomal, Electron Transport, Ferric Compounds, Fresh Water, Geologic Sediments, Gram-Negative Anaerobic Bacteria, Hot Temperature, Molecular Sequence Data, RNA, Ribosomal, 16S, Sequence Analysis, DNA},
	issn = {0099-2240},
	author = {Kashefi, Kazem and Holmes, Dawn E and Reysenbach, Anna-Louise and Lovley, Derek R}
}
