@article {469,
	title = {Polar lipid fatty acids, LPS-hydroxy fatty acids, and respiratory quinones of three Geobacter strains, and variation with electron acceptor.},
	journal = {J Ind Microbiol Biotechnol},
	volume = {36},
	year = {2009},
	month = {2009 Feb},
	pages = {205-9},
	abstract = {The polar lipid fatty acids, lipopolysaccharide hydroxy-fatty acids, and respiratory quinones of Geobacter metallireducens str. GS-15, Geobacter sulfurreducens str. PCA, and Geobacter bemidjiensis str. Bem are reported. Also, the lipids of G. metallireducens were compared when grown with Fe(3+) or nitrate as electron acceptors and G. sulfurreducens with Fe(3+) or fumarate. In all experiments, the most abundant polar lipid fatty acids were 14:0, i15:0, 16:1 omega 7c, 16:1 omega 5c, and 16:0; lipopolysaccharide hydroxy-fatty acids were dominated by 3oh16:0, 3oh14:0, 9oh16:0, and 10oh16:0; and menaquinone-8 was the most abundant respiratory quinone. Some variation in lipid profiles with strain were observed, but not with electron acceptor.},
	keywords = {Culture Media, Electrons, Environmental Microbiology, Fatty Acids, Ferrous Compounds, Geobacter, Lipids, Lipopolysaccharides, Nitrates, Quinones, Vitamin K 2},
	issn = {1476-5535},
	doi = {10.1007/s10295-008-0486-7},
	author = {Hedrick, D B and Peacock, A D and Lovley, D R and Woodard, T L and Nevin, K P and Long, P E and White, D C}
}
@article {479,
	title = {Power output and columbic efficiencies from biofilms of Geobacter sulfurreducens comparable to mixed community microbial fuel cells.},
	journal = {Environ Microbiol},
	volume = {10},
	year = {2008},
	month = {2008 Oct},
	pages = {2505-14},
	abstract = {It has been previously noted that mixed communities typically produce more power in microbial fuel cells than pure cultures. If true, this has important implications for the design of microbial fuel cells and for studying the process of electron transfer on anode biofilms. To further evaluate this, Geobacter sulfurreducens was grown with acetate as fuel in a continuous flow {\textquoteright}ministack{\textquoteright} system in which the carbon cloth anode and cathode were positioned in close proximity, and the cation-selective membrane surface area was maximized in order to overcome some of the electrochemical limitations that were inherent in fuel cells previously employed for the study of pure cultures. Reducing the size of the anode in order to eliminate cathode limitation resulted in maximum current and power densities per m(2) of anode surface of 4.56 A m(-2) and 1.88 W m(-2) respectively. Electron recovery as current from acetate oxidation was c. 100\% when oxygen diffusion into the system was minimized. This performance is comparable to the highest levels previously reported for mixed communities in similar microbial fuel cells and slightly higher than the power output of an anaerobic sludge inoculum in the same ministack system. Minimizing the volume of the anode chamber yielded a volumetric power density of 2.15 kW m(-3), which is the highest power density per volume yet reported for a microbial fuel cell. Geobacter sulfurreducens formed relatively uniform biofilms 3-18 mum thick on the carbon cloth anodes. When graphite sticks served as the anode, the current density (3.10 A m(-2)) was somewhat less than with the carbon cloth anodes, but the biofilms were thicker (c. 50 mum) with a more complex pillar and channel structure. These results suggest that the previously observed disparity in power production in pure and mixed culture microbial fuel cell systems can be attributed more to differences in the fuel cell designs than to any inherent superior capability of mixed cultures to produce more power than pure cultures.},
	keywords = {Acetic Acid, Biofilms, Carbon, Electricity, Electrodes, Geobacter, Oxidation-Reduction},
	issn = {1462-2920},
	doi = {10.1111/j.1462-2920.2008.01675.x},
	author = {Nevin, K P and Richter, H and Covalla, S F and Johnson, J P and Woodard, T L and Orloff, A L and Jia, H and Zhang, M and Lovley, D R}
}
@article {524,
	title = {Characterization of metabolism in the Fe(III)-reducing organism Geobacter sulfurreducens by constraint-based modeling.},
	journal = {Appl Environ Microbiol},
	volume = {72},
	year = {2006},
	month = {2006 Feb},
	pages = {1558-68},
	abstract = {Geobacter sulfurreducens is a well-studied representative of the Geobacteraceae, which play a critical role in organic matter oxidation coupled to Fe(III) reduction, bioremediation of groundwater contaminated with organics or metals, and electricity production from waste organic matter. In order to investigate G. sulfurreducens central metabolism and electron transport, a metabolic model which integrated genome-based predictions with available genetic and physiological data was developed via the constraint-based modeling approach. Evaluation of the rates of proton production and consumption in the extracellular and cytoplasmic compartments revealed that energy conservation with extracellular electron acceptors, such as Fe(III), was limited relative to that associated with intracellular acceptors. This limitation was attributed to lack of cytoplasmic proton consumption during reduction of extracellular electron acceptors. Model-based analysis of the metabolic cost of producing an extracellular electron shuttle to promote electron transfer to insoluble Fe(III) oxides demonstrated why Geobacter species, which do not produce shuttles, have an energetic advantage over shuttle-producing Fe(III) reducers in subsurface environments. In silico analysis also revealed that the metabolic network of G. sulfurreducens could synthesize amino acids more efficiently than that of Escherichia coli due to the presence of a pyruvate-ferredoxin oxidoreductase, which catalyzes synthesis of pyruvate from acetate and carbon dioxide in a single step. In silico phenotypic analysis of deletion mutants demonstrated the capability of the model to explore the flexibility of G. sulfurreducens central metabolism and correctly predict mutant phenotypes. These results demonstrate that iterative modeling coupled with experimentation can accelerate the understanding of the physiology of poorly studied but environmentally relevant organisms and may help optimize their practical applications.},
	keywords = {Amino Acids, Electron Transport, Escherichia coli, Fumarates, Geobacter, Iron, Models, Biological, Mutation, Oxidation-Reduction, Phenotype, Protons, Quinones, Species Specificity},
	issn = {0099-2240},
	doi = {10.1128/AEM.72.2.1558-1568.2006},
	author = {Mahadevan, R and Bond, D R and Butler, J E and Esteve-Nu{\~n}ez, A and Coppi, M V and Palsson, B O and Schilling, C H and Lovley, D R}
}
@article {531,
	title = {Adaptation to disruption of the electron transfer pathway for Fe(III) reduction in Geobacter sulfurreducens.},
	journal = {J Bacteriol},
	volume = {187},
	year = {2005},
	month = {2005 Sep},
	pages = {5918-26},
	abstract = {Previous studies demonstrated that an outer membrane c-type cytochrome, OmcB, was involved in Fe(III) reduction in Geobacter sulfurreducens. An OmcB-deficient mutant was greatly impaired in its ability to reduce both soluble and insoluble Fe(III). Reintroducing omcB restored the capacity for Fe(III) reduction at a level proportional to the level of OmcB production. Here, we report that the OmcB-deficient mutant gradually adapted to grow on soluble Fe(III) but not insoluble Fe(III). The adapted OmcB-deficient mutant reduced soluble Fe(III) at a rate comparable to that of the wild type, but the cell yield of the mutant was only ca. 60\% of that of the wild type under steady-state culturing conditions. Analysis of proteins and transcript levels demonstrated that expression of several membrane-associated cytochromes was higher in the adapted mutant than in the wild type. Further comparison of transcript levels during steady-state growth on Fe(III) citrate with a whole-genome DNA microarray revealed a significant shift in gene expression in an apparent attempt to adapt metabolism to the impaired electron transport to Fe(III). These results demonstrate that, although there are many other membrane-bound c-type cytochromes in G. sulfurreducens, increased expression of these cytochromes cannot completely compensate for the loss of OmcB. The concept that outer membrane cytochromes are promiscuous reductases that are interchangeable in function appears to be incorrect. Furthermore, the results indicate that there may be different mechanisms for electron transfer to soluble Fe(III) and insoluble Fe(III) oxides in G. sulfurreducens, which emphasizes the importance of studying electron transport to the environmentally relevant Fe(III) oxides.},
	keywords = {Adaptation, Physiological, Bacterial Outer Membrane Proteins, Base Sequence, Cytochromes c, DNA Primers, Electron Transport, Ferric Compounds, Gene Expression Regulation, Bacterial, Geobacter, Kinetics, Oxidation-Reduction, Reverse Transcriptase Polymerase Chain Reaction},
	issn = {0021-9193},
	doi = {10.1128/JB.187.17.5918-5926.2005},
	author = {Leang, Ching and Adams, L A and Chin, K-J and Nevin, K P and Meth{\'e}, B A and Webster, J and Sharma, M L and Lovley, D R}
}
@article {527,
	title = {Outer membrane c-type cytochromes required for Fe(III) and Mn(IV) oxide reduction in Geobacter sulfurreducens.},
	journal = {Appl Environ Microbiol},
	volume = {71},
	year = {2005},
	month = {2005 Dec},
	pages = {8634-41},
	abstract = {The potential role of outer membrane proteins in electron transfer to insoluble Fe(III) oxides by Geobacter sulfurreducens was investigated because this organism is closely related to the Fe(III) oxide-reducing organisms that are predominant in many Fe(III)-reducing environments. Two of the most abundant proteins that were easily sheared from the outer surfaces of intact cells were c-type cytochromes. One, designated OmcS, has a molecular mass of ca. 50 kDa and is predicted to be an outer membrane hexaheme c-type cytochrome. Transcripts for omcS could be detected during growth on Fe(III) oxide, but not on soluble Fe(III) citrate. The omcS mRNA consisted primarily of a monocistronic transcript, and to a lesser extent, a longer transcript that also contained the downstream gene omcT, which is predicted to encode a second hexaheme outer membrane cytochrome with 62.6\% amino acid sequence identity to OmcS. The other abundant c-type cytochrome sheared from the outer surface of G. sulfurreducens, designated OmcE, has a molecular mass of ca. 30 kDa and is predicted to be an outer membrane tetraheme c-type cytochrome. When either omcS or omcE was deleted, G. sulfurreducens could no longer reduce Fe(III) oxide but could still reduce soluble electron acceptors, including Fe(III) citrate. The mutants could reduce Fe(III) in Fe(III) oxide medium only if the Fe(III) chelator, nitrilotriacetic acid, or the electron shuttle, anthraquinone 2,6-disulfonate, was added. Expressing omcS or omcE in trans restored the capacity for Fe(III) oxide reduction. OmcT was not detected among the sheared proteins, and genetic studies indicated that G. sulfurreducens could not reduce Fe(III) oxide when omcT was expressed but OmcS was absent. In contrast, Fe(III) oxide was reduced when omcS was expressed in the absence of OmcT. These results suggest that OmcS and OmcE are involved in electron transfer to Fe(III) oxides in G. sulfurreducens. They also emphasize the importance of evaluating mechanisms for Fe(III) reduction with environmentally relevant Fe(III) oxide, rather than the more commonly utilized Fe(III) citrate, because additional electron transfer components are required for Fe(III) oxide reduction that are not required for Fe(III) citrate reduction.},
	keywords = {Amino Acid Sequence, Bacterial Outer Membrane Proteins, Bacterial Proteins, Base Sequence, Cytochromes c, DNA Primers, Ferric Compounds, Geobacter, Kinetics, Manganese Compounds, Molecular Sequence Data, Oxidation-Reduction, Oxides, Peptide Fragments},
	issn = {0099-2240},
	doi = {10.1128/AEM.71.12.8634-8641.2005},
	author = {Mehta, T and Coppi, M V and Childers, S E and Lovley, D R}
}
@article {557,
	title = {Geobacter sulfurreducens can grow with oxygen as a terminal electron acceptor.},
	journal = {Appl Environ Microbiol},
	volume = {70},
	year = {2004},
	month = {2004 Apr},
	pages = {2525-8},
	abstract = {Geobacter sulfurreducens, previously classified as a strict anaerobe, tolerated exposure to atmospheric oxygen for at least 24 h and grew with oxygen as the sole electron acceptor at concentrations of 10\% or less in the headspace. These results help explain how Geobacter species may survive in oxic subsurface environments, being poised to rapidly take advantage of the development of anoxic conditions.},
	keywords = {Aerobiosis, Anaerobiosis, Electron Transport, Environmental Microbiology, Geobacter, Oxygen},
	issn = {0099-2240},
	author = {Lin, W C and Coppi, M V and Lovley, D 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 {562,
	title = {Genome of Geobacter sulfurreducens: metal reduction in subsurface environments.},
	journal = {Science},
	volume = {302},
	year = {2003},
	month = {2003 Dec 12},
	pages = {1967-9},
	abstract = {The complete genome sequence of Geobacter sulfurreducens, a delta-proteobacterium, reveals unsuspected capabilities, including evidence of aerobic metabolism, one-carbon and complex carbon metabolism, motility, and chemotactic behavior. These characteristics, coupled with the possession of many two-component sensors and many c-type cytochromes, reveal an ability to create alternative, redundant, electron transport networks and offer insights into the process of metal ion reduction in subsurface environments. As well as playing roles in the global cycling of metals and carbon, this organism clearly has the potential for use in bioremediation of radioactive metals and in the generation of electricity.},
	keywords = {Acetates, Acetyl Coenzyme A, Aerobiosis, Anaerobiosis, Bacterial Proteins, Carbon, Chemotaxis, Chromosomes, Bacterial, Cytochromes c, Electron Transport, Energy Metabolism, Genes, Bacterial, Genes, Regulator, Genome, Bacterial, Geobacter, Hydrogen, Metals, Movement, Open Reading Frames, Oxidation-Reduction, Phylogeny},
	issn = {1095-9203},
	doi = {10.1126/science.1088727},
	author = {Meth{\'e}, B A and Nelson, K E and Eisen, J A and Paulsen, I T and Nelson, W and Heidelberg, J F and Wu, D and Wu, M and Ward, N and Beanan, M J and Dodson, R J and Madupu, R and Brinkac, L M and Daugherty, S C and DeBoy, R T and Durkin, A S and Gwinn, M and Kolonay, J F and Sullivan, S A and Haft, D H and Selengut, J and Davidsen, T M and Zafar, N and White, O and Tran, B and Romero, C and Forberger, H A and Weidman, J and Khouri, H and Feldblyum, T V and Utterback, T R and Van Aken, S E and Lovley, D R and Fraser, C M}
}
