@article {589,
	title = {A hydrogen-based subsurface microbial community dominated by methanogens.},
	journal = {Nature},
	volume = {415},
	year = {2002},
	month = {2002 Jan 17},
	pages = {312-5},
	abstract = {The search for extraterrestrial life may be facilitated if ecosystems can be found on Earth that exist under conditions analogous to those present on other planets or moons. It has been proposed, on the basis of geochemical and thermodynamic considerations, that geologically derived hydrogen might support subsurface microbial communities on Mars and Europa in which methanogens form the base of the ecosystem. Here we describe a unique subsurface microbial community in which hydrogen-consuming, methane-producing Archaea far outnumber the Bacteria. More than 90\% of the 16S ribosomal DNA sequences recovered from hydrothermal waters circulating through deeply buried igneous rocks in Idaho are related to hydrogen-using methanogenic microorganisms. Geochemical characterization indicates that geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. These results demonstrate that hydrogen-based methanogenic communities do occur in Earth{\textquoteright}s subsurface, providing an analogue for possible subsurface microbial ecosystems on other planets.},
	keywords = {Bacteria, DNA, Archaeal, DNA, Bacterial, Ecosystem, Euryarchaeota, Exobiology, Hydrogen, Molecular Sequence Data, Phylogeny, RNA, Ribosomal, 16S, Water Microbiology},
	issn = {0028-0836},
	doi = {10.1038/415312a},
	author = {Chapelle, Francis H and O{\textquoteright}Neill, Kathleen and Bradley, Paul M and Meth{\'e}, Barbara A and Ciufo, Stacy A and Knobel, LeRoy L and Lovley, Derek R}
}
@article {585,
	title = {Reduction of Fe(III) oxide by methanogens in the presence and absence of extracellular quinones.},
	journal = {Environ Microbiol},
	volume = {4},
	year = {2002},
	month = {2002 Feb},
	pages = {115-24},
	abstract = {Five methanogens (Methanosarcina barkeri MS, Methanosphaera cuniculi 1R7, Methanobacterium palustre F, Methanococcus voltaei A3 and Methanolobus vulcani PL-12/M) were investigated for their ability to reduce Fe(III) oxide and the soluble quinone anthraquinone-2,6-disulphonate (AQDS). Two species (M. barkeri and M. voltaei) reduced significant amounts of Fe(III) oxide using hydrogen as the electron donor, and 0.1 mM AQDS greatly accelerated Fe(III) reduction by these organisms. Although Fe(III) appeared to inhibit growth and methanogenesis of some strains, hydrogen partial pressures under donor-limited conditions were much lower (<0.5 Pa) in the presence of Fe(III) than in normal media (1-10 Pa) for all species except for M. vulcani. These results demonstrate that electrons were transferred to Fe(III) by hydrogen-utilizing methanogens even when growth and methanogenesis were inhibited. All species except the obligate methylotroph M. vulcani were able to reduce AQDS when their growth substrates were present as electron donors, and rates were highest when organisms used hydrogen as the electron donor. Purified soil humic acids could also be reduced by the AQDS-reducing methanogens. The ability of methanogens to interact with extracellular quinones, humic acids and Fe(III) oxides raises the possibility that this functional group of organ-isms contributes to Fe(III) and humic acid reduction under certain conditions in the environment and provides an alternative explanation for the inhibition of methanogenesis in some Fe(III)-containing ecosystems.},
	keywords = {Anthraquinones, Euryarchaeota, Ferric Compounds, Humic Substances, Oxidation-Reduction, Species Specificity},
	issn = {1462-2912},
	author = {Bond, Daniel R and Lovley, Derek R}
}
@article {591,
	title = {Bioremediation. Anaerobes to the rescue.},
	journal = {Science},
	volume = {293},
	year = {2001},
	month = {2001 Aug 24},
	pages = {1444-6},
	keywords = {Bacteria, Aerobic, Bacteria, Anaerobic, Biodegradation, Environmental, Euryarchaeota, Ferric Compounds, Genome, Archaeal, Genome, Bacterial, Hydrocarbons, Aromatic, Hydrocarbons, Chlorinated, Metals, Methane, Nitrates, Oxidation-Reduction, Oxygen, Soil Microbiology, Sulfates, Sulfur-Reducing Bacteria, Water Pollutants, Chemical},
	issn = {0036-8075},
	doi = {10.1126/science.1063294},
	author = {Lovley, D R}
}
@article {867,
	title = {Methane production and release from two New England peatlands.},
	journal = {Int Microbiol},
	volume = {3},
	year = {2000},
	month = {2000 Jun},
	pages = {89-95},
	abstract = {The rate of methane production and release to the atmosphere was determined for two New England peat bogs. Methane production rates from peat sediments, which were measured down to depths of 150 cm, ranged from 1 to 15 micromoles per liter per hour. The highest rates of methane production occurred at depths of 60-100 cm. Methane release from these same peats was quantified from various habitats on the bog using gas collection chambers. The chambers enclose a two-liter volume and cover an area of 0.02 m2. Methane accumulation in the chambers was measured for periods of up to 18 days. Methane release was related to pH and habitat zone. The lowest rates of methane release were from those portions of the bogs that had pH values below 5.0. Peak methane release occurred during or immediately after ice melt in both wetlands with release rates as high as 34 mmoles/m2/d. The overall estimate of yearly release of methane from these bog systems is 2,900 and 14,900 moles per year for Arcadia and Hawley Bogs respectively. Both of these bogs have pH environments close to the lowest limit for methanogenesis, and small differences in pH values can have a large impact on both the rate of methane production and the rate of methane release to the atmosphere.},
	keywords = {Anaerobiosis, Euryarchaeota, Hydrogen-Ion Concentration, Methane, New England, Soil, Soil Microbiology},
	issn = {1139-6709},
	author = {Duval, B and Goodwin, S}
}
@article {872,
	title = {Acetate catabolism in the dissimilatory iron-reducing isolate GS-15.},
	journal = {J Bacteriol},
	volume = {173},
	year = {1991},
	month = {1991 Apr},
	pages = {2704-6},
	abstract = {Acetate-grown GS-15 whole-cell suspensions were disrupted with detergent and assayed for enzymes associated with acetate catabolism. Carbon monoxide dehydrogenase and formate dehydrogenase were not observed in GS-15. Catabolic levels of acetokinase and phosphotransacetylase were observed. Enzyme activities of the citric acid cycle, i.e., isocitrate dehydrogenase, 2-oxoglutarate sythase, succinate dehydrogenase, fumarase, and malate dehydrogenase, were observed.},
	keywords = {Acetate Kinase, Acetates, Acetyl Coenzyme A, Bacteria, Carbon Monoxide, Citric Acid Cycle, Electron Transport, Euryarchaeota, Fumarate Hydratase, Isocitrate Dehydrogenase, Ketone Oxidoreductases, Malate Dehydrogenase, Phosphate Acetyltransferase, Pseudomonas aeruginosa, Succinate Dehydrogenase},
	issn = {0021-9193},
	author = {Champine, J E and Goodwin, S}
}
@article {669,
	title = {Identification of methyl coenzyme M as an intermediate in methanogenesis from acetate in Methanosarcina spp.},
	journal = {J Bacteriol},
	volume = {160},
	year = {1984},
	month = {1984 Nov},
	pages = {521-5},
	abstract = {The transfer of the methyl group of acetate to coenzyme M (2-mercaptoethanesulfonic acid; HS-CoM) during the metabolism of acetate to methane was investigated in cultures of Methanosarcina strain TM-1. The organism metabolized CD3COO- to 83\% CD3H and 17\% CD2H2 and produced no CDH3 or CH4. The isotopic composition of coenzyme M in cells grown on CD3COO- was analyzed with a novel gas chromatography-mass spectrometry technique. The cells contained CD3-D-CoM and CD2H-S-CoM) in a proportion similar to that of CD3H to CD2H2. These results, in conjunction with a report (J.K. Nelson and J.G. Ferry, J. Bacteriol. 160:526-532, 1984) that extracts of acetate-grown strain TM-1 contain high levels of CH3-S-CoM methylreductase, indicate that CH3-S-CoM is an intermediate in the metabolism of acetate to methane in this organism.},
	keywords = {Acetates, Deuterium, Euryarchaeota, Gas Chromatography-Mass Spectrometry, Mercaptoethanol, Mesna, Methane, Methylation},
	issn = {0021-9193},
	author = {Lovley, D R and White, R H and Ferry, J G}
}
@article {670,
	title = {Rapidly growing rumen methanogenic organism that synthesizes coenzyme M and has a high affinity for formate.},
	journal = {Appl Environ Microbiol},
	volume = {48},
	year = {1984},
	month = {1984 Jul},
	pages = {81-7},
	abstract = {Methanogenic bacteria with a coccobacillus morphology similar to Methanobrevibacter ruminantium were isolated from the bovine rumen. One isolate, 10-16B, represented a previously undescribed rumen population that, unlike M. ruminantium, synthesized coenzyme M, grew rapidly (mu = 0.24 h-1) on H2-CO2 in a complex medium, had simple nutritional requirements, and metabolized formate at reported rumen concentrations. H2 was metabolized to partial pressures 10-fold lower than those reported for the rumen. After H2 starvation for 26 h, strain 10-16B rapidly resumed growth when H2 was made available. The minimum concentrations of acetate (6 mM) and ammonia (less than 7 mM) that were required for optimal growth were lower than the reported acetate and ammonia concentrations in the rumen. Isoleucine and leucine stimulated growth, but only at concentrations (greater than 50 microM) higher than those reported for the rumen. Another coccobacillary methanogenic organism that synthesized coenzyme M was isolated from a different animal as were organisms that required an exogenous supply of coenzyme M. In general, methanogenic bacteria that required an exogenous supply of coenzyme M had lower maximum growth rates and more complex nutritional requirements than organisms that synthesized the cofactor. The ability of all isolates to metabolize formate below the detection limit of 10 microM indicated that, in contrast to previous reports, methanogenic bacteria have the potential to directly metabolize formate in the rumen. This study demonstrated that there are physiologically diverse populations of coccobacillary methanogenic bacteria in the rumen that can interact competitively and cooperatively.},
	keywords = {Animals, Cattle, Culture Media, Enzyme Induction, Euryarchaeota, Formates, Hydrogen, Male, Mercaptoethanol, Mesna, Rumen, Substrate Specificity},
	issn = {0099-2240},
	author = {Lovley, D R and Greening, R C and Ferry, J G}
}
