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G. Gales,
N. Chehider,
C. Joulian,
F. Battaglia-Brunet,
J.-L. Cayol,
A. Postec,
J. Borgomano,
I. Neria-Gonzalez,
B. P. Lomans, B. Ollivier,
D. Alazard
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ABSTRACT: An anaerobic, halophilic, and fermentative bacterium, strain S200T, was isolated from a core sample of a deep hypersaline oil reservoir. Cells were rod-shaped, non-motile, and stained Gram-positive.
It grew at NaCl concentrations ranging from 6 to 26% (w/v), with optimal growth at 15% (w/v) NaCl, and at temperatures between
25 and 47°C with an optimum at 40–45°C. The optimum pH was 7.3 (range 6.2–8.8; no growth at pH 5.8 and pH 9). The doubling
time in optimized growth conditions was 3.5h. Strain S200T used exclusively carbohydrates as carbon and energy sources. The end products of glucose degradation were lactate, formate,
ethanol, acetate, H2, and CO2. The predominant cellular fatty acids were non-branched fatty acids C16:1, C16:0, and C14:0. The G+C mole% of the DNA was 32.7%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain S200T formed a distinct lineage within the family Halobacteroidaceae, order Halanaerobiales, and was most closely related to Halanaerobaculum tunisiense DSM 19997T and Halobacteroides halobius DSM 5150T, with sequence similarity of 92.3 and 91.9%, respectively. On the basis of its physiological and genotypic properties, strain
S200T is proposed to be assigned to a novel species of a novel genus, for which the name Halanaerocella petrolearia is proposed. The type strain of Halanaerocella petrolearia is strain S200T (=DSM 22693T=JCM 16358T).
KeywordsAnaerobic–Halophilic–Taxonomy–
Halanaerocella petrolearia
–Oil reservoir
Extremophiles 04/2012; 15(5):565-571. · 2.94 Impact Factor
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ABSTRACT: While developing a low-sulphate system combining indirect chromate-reduction by biologically-produced hydrogen sulphide and
direct biological chromate-reduction to treat chromate-bearing waters, the aim of the present work was to evaluate the influence
of sulphate and H2 starvation on chromate reduction. Chromate-reduction was performed under continuous-feed conditions in a fixed-film column
bioreactor originally inoculated with a bacterial consortium containing Desulfomicrobium norvegicum, and fed with H2. With 500mg l−1 of sulphate in the feed solution, total chromate-reduction was observed in the effluent whereas sulphate-reduction was strongly
decreased, as also confirmed by measurements of isotopic ratios for sulphur. In the absence of sulphate, a chromate-reduction
activity was still observed but was lower than in the presence of sulphate, and chromate-reduction was H2-dependent. Molecular biology techniques revealed the composition of the bacterial population in the effluent. D. norvegicum together with other micro-organisms of the Bacteria domain were detected. They include members related to the genera Acinetobacter, Acetobacterium and Rhodocyclus. Even when sulphate-reduction was strongly decreased, the presence of sulphate enhances the efficiency of the H2-dependent chromate-reduction. A H2- and CO2-consuming bacterial population may be used in a globally autotrophic process to reduce chromate at low sulphate concentration,
thus avoiding excess sulphide production.
Water Air and Soil Pollution 04/2012; 183(1):341-353. · 1.63 Impact Factor
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G Gales,
N Chehider,
C Joulian,
F Battaglia-Brunet,
J-L Cayol,
A Postec,
J Borgomano,
I Neria-Gonzalez,
B P Lomans, B Ollivier,
D Alazard
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ABSTRACT: An anaerobic, halophilic, and fermentative bacterium, strain S200(T), was isolated from a core sample of a deep hypersaline oil reservoir. Cells were rod-shaped, non-motile, and stained Gram-positive. It grew at NaCl concentrations ranging from 6 to 26% (w/v), with optimal growth at 15% (w/v) NaCl, and at temperatures between 25 and 47°C with an optimum at 40-45°C. The optimum pH was 7.3 (range 6.2-8.8; no growth at pH 5.8 and pH 9). The doubling time in optimized growth conditions was 3.5 h. Strain S200(T) used exclusively carbohydrates as carbon and energy sources. The end products of glucose degradation were lactate, formate, ethanol, acetate, H(2), and CO(2). The predominant cellular fatty acids were non-branched fatty acids C(16:1), C(16:0), and C(14:0). The G + C mole% of the DNA was 32.7%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain S200(T) formed a distinct lineage within the family Halobacteroidaceae, order Halanaerobiales, and was most closely related to Halanaerobaculum tunisiense DSM 19997(T) and Halobacteroides halobius DSM 5150(T), with sequence similarity of 92.3 and 91.9%, respectively. On the basis of its physiological and genotypic properties, strain S200(T) is proposed to be assigned to a novel species of a novel genus, for which the name Halanaerocella petrolearia is proposed. The type strain of Halanaerocella petrolearia is strain S200(T) (=DSM 22693(T) = JCM 16358(T)).
Extremophiles 09/2011; 15(5):565-71. · 2.94 Impact Factor
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ABSTRACT: Two novel sulfate-reducing bacterial strains, designated E-2(T) and IMP-2, were isolated from geographically distinct locations. Strain E-2(T) was recovered from marine sediments near Sfax (Tunisia), whereas strain IMP-2 originated from oilfield production fluids in the Gulf of Mexico. Cells were Gram-negative, non-sporulated, motile, vibrio-shaped or sigmoid. They were strictly anaerobic, mesophilic and moderately halophilic. Sulfate, sulfite, thiosulfate and elemental sulfur served as electron acceptors, but not nitrate or nitrite. H(2) (with acetate as carbon source), formate, fumarate, lactate, malate, pyruvate, succinate and fructose were used as electron donors in the presence of sulfate as terminal electron acceptor. Lactate was oxidized incompletely to acetate. Fumarate and pyruvate were fermented. Desulfoviridin and c-type cytochromes were present. 16S rRNA gene sequence analysis of the two strains showed that they were phylogenetically similar (99.0 % similarity) and belonged to the genus Desulfovibrio, with Desulfovibrio indonesiensis and Desulfovibrio gabonensis as their closest phylogenetic relatives. The G+C content of the DNA was respectively 60.4 and 62.7 mol% for strains E-2(T) and IMP-2. DNA-DNA hybridization experiments revealed that the novel strains had a high genomic relatedness, suggesting that they belong to the same species. We therefore propose that the two isolates be affiliated to a novel species of the genus Desulfovibrio, Desulfovibrio marinus sp. nov. The type strain is strain E-2(T) (=DSM 18311(T) =JCM 14040(T)).
International journal of systematic and evolutionary microbiology 10/2007; 57(Pt 9):2167-70. · 2.27 Impact Factor
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ABSTRACT: A disc-shaped methanogenic bacterium designated strain SEBR 4847T (T=type strain) was isolated from a sample collected from an African offshore oil field. Strain SEBR 4847T was non-motile, had a G+C content of 50 mol% and produced methane from H2+CO2, formate, and CO2+propanol. Strain SEBR 4847T grew optimally at 37°C; no growth was observed at 25°C or 45°C. It grew in the presence of up to 50 g/l NaCl; 10–30 g/l was required for optimal growth. The optimum pH for growth was 7.0. Doubling time was about 10 h under optimal conditions. Based on 16S rRNA sequence analysis, the isolate was identified as a new species of the genus Methanoplanus and designated Methanoplanus petrolearius sp. nov. The type strain is SEBR 4847T (=OCM 486).
FEMS Microbiology Letters 01/2006; 147(1):51 - 56. · 2.04 Impact Factor
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ABSTRACT: Mesophilic, hydrogenotrophic, sulfate-reducing bacteria were isolated from a deep-sea hydrothermal chimney sample collected at 13 degrees N on the East-Pacific Rise at a depth of 2,600 m. Two strains (BL5 and H9) were found to be phylogenetically similar to Desulfovibrio profundus (similarity >99%), whereas two other strains (H1 and AM13T) were found to be phylogenetically distinct (similarity 96.4%) from Desulfovibrio zosterae, their closest relative. Strain AM13T was characterized further. It was a barophilic, Gram-negative, non-sporulating, motile, vibrio-shaped or sigmoid bacterium possessing desulfoviridin. It grew at temperatures ranging from 20 to 40 degrees C, with an optimum at 35 degrees C in the presence of 2.5% NaCl. The pH range for growth was 6.7-8.2 with an optimum around 7.8. Strain AM13T utilized H2/CO2, lactate, formate, ethanol, choline and glycerol as electron donors. Electron acceptors were sulfate, sulfite and thiosulfate, but not elemental sulfur or nitrate. The G + C content of DNA was 47 mol%. Strain AM13T (= DSM 14728T = CIP107303T) differed from D. zosterae not only phylogenetically, but also genomically (DNA-DNA reassociation value between the two bacteria was 23.8%) and phenotypically. This isolate is therefore proposed as the type strain of a novel species of the genus Desulfovibrio, Desulfovibrio hydrothermalis sp. nov.
International journal of systematic and evolutionary microbiology 01/2003; 53(Pt 1):173-8. · 2.27 Impact Factor
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ABSTRACT: A new gram-positive, facultative anaerobic, microaerophilic bacterium, designated strain M5T, was isolated from a decantation reservoir of olive mill wastewater. The cells were rod-shaped, non-motile, non-spore-forming and catalase-negative. Growth occurred at pH ranging from 4.5 to 9.5, with optimum growth at 7.0. The optimum temperature for growth was around 30 degrees C. Although growth occurred under anaerobic and aerobic conditions, the optimum O2 concentration for growth was determined as 5% in the gas phase of the culture. During anaerobic growth, glucose or lactate were mainly fermented to propionate, acetate and CO2. In the presence of O2 (more than 2%), glucose was oxidized completely to CO2. The G+C content of the DNA was 67.7+/-0.6 mol% and 16S rRNA gene analysis revealed that the new isolate belonged to the cluster of 'dairy' propionibacteria, Propionibacterium acidipropionici being its closest phylogenic relative (97.5% similarity). However, the level of DNA relatedness between strain M5T and P. acidipropionici was 56.2%. Consequently, both the phenotypic (range of substrates used) and genotypic characteristics of strain M5T allow it to be assigned as a new species of the genus Propionibacterium, Propionibacterium microaerophilum sp. nov. The type strain is strain M5T (= CNCM I-2360T = DSM 13435T).
International journal of systematic and evolutionary microbiology 08/2001; 51(Pt 4):1373-82. · 2.27 Impact Factor
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ABSTRACT: 16S rRNA sequencing and sequence analysis of the sole member of the genus Thermobacteroides, Thermobacteroides leptospartum, revealed that it was related to members of cluster III (according to the scheme of Collins et al. 1994) represented exclusively by cellulolytic Clostridium species. Phenotypic studies indicated that Thermobacteroides leptospartum was also able to grow on cellulose, providing further evidence of its affiliation to members of cluster III. Its closest phylogenetic relatives, Clostridium thermolacticum and Clostridium stercorarium, were almost equidistantly placed with a similarity value of 99%. DNA hybridization studies also indicated that Thermobacteroides leptospartum, C. thermolacticum and C. stercorarium were closely related to each other (values of over 95% homology). Similarities based on the comparison of the 16S rRNA gene sequences and DNA homology are sufficiently high to regard all three strains as subspecies of a single species. It is therefore proposed that Thermobacteroides leptospartum and C. thermolacticum be transferred to cluster III as C. stercorarium subsp. leptospartum subsp. nov., comb. nov. and C. stercorarium subsp. thermolacticum subsp. nov., comb. nov., respectively, thus automatically creating C. stercorarium subsp. stercorarium subsp. nov., comb. nov. The transfer of the sole member of Thermobacteroides invalidates the taxonomic status of the genus.
International journal of systematic and evolutionary microbiology 06/2001; 51(Pt 3):1127-31. · 2.27 Impact Factor
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ABSTRACT: A new thermophilic, anaerobic glucose-fermenting, Gram-positive, rod-shaped bacterium, designated strain SEBR 7858T, was isolated from an oilfield water sample. Under optimal conditions on a glucose-containing medium (3% NaCl, 65 degrees C and pH 7.5), the generation time was 2.5 h. No growth occurred at 35 or 80 degrees C, nor at pH 5..5 or 9.0. Strain SEBR 7858T possessed lateral flagella. Spores were undetected but heat-resistant forms were present. Strain SEBR 7858T fermented a range of carbohydrates to acetate, L-alanine, lactate, H2 and CO2. The isolate reduced thiosulfate and elemental sulfur, but not sulfate or sulfite to sulfide. In the presence of thiosulfate, the ratio of acetate produced per mole of glucose consumed increased, suggesting a shift in the use of electron acceptors during carbohydrate metabolism. The DNA G+C content was 41 mol%. Based on 16S rRNA gene sequence analysis, the strain was almost equidistantly related to all members of the genus Thermoanaerobacter (mean similarity 92%). Based on phenotypic, genomic and phylogenetic characteristics, strain SEBR 7858T was clearly different from all members of the genus Thermoanaerobacter and was therefore designated as a new species, Thermoanaerobacter subterraneus sp. nov. The type strain is SEBR 7858T (= CNCM 1-2383T, DSM 13054T).
International journal of systematic and evolutionary microbiology 12/2000; 50 Pt 6:2141-9. · 2.27 Impact Factor
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Anaerobe 09/2000; 6(4):205-26. · 2.41 Impact Factor
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ABSTRACT: A rod (0.3-0.4 micron x 3-10 microns) to filamentous (up to 40 microns) non-motile methanogenic bacterium, designated strain FPiT (T = type strain), was isolated from ricefield soil in the Philippines. The strain uses H2 + CO2 or formate for growth and produces CH4. Optimum growth temperature is 40 degrees C; no growth is observed at 15 degrees C or 45 degrees C. Optimum pH for growth is 7; no growth is observed at pH 5.5 or 9.0. Strain FPiT is halotolerant and grows at NaCl concentrations of 0-25 g l-1. The G + C content of its DNA is 31 mol%. Based on 16S rRNA gene sequence analysis, the isolate was identified as a new species of the genus Methanobacterium: Methanobacterium oryzae sp. nov. The type strain is FPiT (= DSM 11106T).
International journal of systematic and evolutionary microbiology 04/2000; 50 Pt 2:525-8. · 2.27 Impact Factor
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ABSTRACT: A new thermophilic, strictly halophilic, anaerobic, non-sporulating rod-shaped bacterium, measuring 0.5 x 3.0-8.0 microns and designated strain CTT3T, was isolated from a solar saltern. Strain CTT3T stained Gram-negative, was motile by means of laterally inserted flagella, had a genome G + C content of 33 mol% and grew optimally at 65 degrees C and pH 7.0 with 5% NaCl. The strain also grew readily at 70 degrees C in the presence of 15% NaCl. Strain CTT3T fermented cellobiose, fructose, glucose, maltose, mannitol, mannose, sucrose, glycerol, N-acetylglucosamine, starch, pyruvate and bio-Trypticase. It produced acetate, ethanol, H2 and presumably CO2 from glucose. 16S rRNA gene sequence analysis indicated that it is a member of cluster XII of the Clostridiales and related genera of the subphylum of the Gram-positive bacteria containing genomes of low G + C content. Its phenotypic and phylogenetic characteristics clearly differentiated it from all other members of this cluster. Based on the findings it is proposed that strain CTT3T be designated as a new species of a new genus, Thermohalobacter berrensis gen. nov., sp. nov. The type strain is CTT3T (= CNCM 105955T).
International journal of systematic and evolutionary microbiology 04/2000; 50 Pt 2:559-64. · 2.27 Impact Factor
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ABSTRACT: Although the importance of bacterial activities in oil reservoirs was recognized a long time ago, our knowledge of the nature and diversity of bacteria growing in these ecosystems is still poor, and their metabolic activities in situ largely ignored. This paper reviews our current knowledge about these bacteria and emphasises the importance of the petrochemical and geochemical characteristics in understanding their presence in such environments.
Antonie van Leeuwenhoek 03/2000; 77(2):103-16. · 2.09 Impact Factor
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ABSTRACT: A novel, curved (0.3 x 4.0-5.0 microm), Gram-negative, non-sporulating, mesophilic bacterium, designated strain ILE-3T (T = type strain), was isolated from an anaerobic lagoon in a dairy wastewater treatment plant. Optimal growth occurred at 37 degrees C and pH 7.4 on a medium containing serine as an energy source and yeast extract. The strain was motile by means of one or two lateral flagella. It required yeast extract for growth on serine, glycine, threonine and pyruvate. Poor growth was obtained on cysteine, Casamino acids, biotrypcase, peptone and 2-oxoglutarate. In the presence of Methanobacterium formicicum, strain ILE-3T oxidized alanine, glutamate, leucine, isoleucine, valine and aspartate to a minor extent. The G+C content of the DNA was 44 mol%. Phylogenetic analysis of the 16S rRNA gene of strain ILE-3T indicated that it was related to Aminobacterium colombiense (95% similarity value). On the basis of the phenotypic and phylogenetic characteristics, strain ILE-3T is designated as a new species of the genus Aminobacterium, namely Aminobacterium mobile sp. nov. (= DSM 12262T).
International journal of systematic and evolutionary microbiology 02/2000; 50 Pt 1:259-64. · 2.27 Impact Factor
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ABSTRACT: 16S rRNA gene sequences of three previously described amino-acid-fermenting anaerobes, Selenomonas acidaminovorans, 'Selenomonas acidaminophila' and Eubacterium acidaminophilum, were determined. All three were found to cluster within the Clostridium and related genera of the subphylum of the Gram-positive bacteria. The thermophile, S. acidaminovorans, formed an individual line of descent and was equidistantly placed between Dethiosulfovibrio peptidovorans and Anaerobaculum thermoterrenum (similarity of 85%), both of which also form single lines of descent. 'S. acidaminophila' was related to Clostridium quercicolum, a member of cluster IX, with a similarity of 90%, whereas E. acidaminophilum was closely related to Clostridium litorale (similarity of 96%) as a member of cluster XI. Based on the phylogenetic data presented in this report and the phenotypic descriptions of these bacteria published previously, it is recommended that S. acidaminovorans be transferred to a new genus, Thermanaerovibrio gen. nov., as Thermanaerovibrio acidaminovorans comb. nov. and 'Selenomonas acidaminophila' be transferred to a new genus, Anaeromusa gen. nov., as Anaeromusa acidaminophila comb. nov. Though the transfer of E. acidaminophilum to a new taxon is justified, this is not recommended until the taxonomic status of all the members of cluster XI has been reviewed.
International journal of systematic bacteriology 08/1999; 49 Pt 3:969-74.
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ABSTRACT: A strictly anaerobic, halotolerant, spindle-shaped rod, designated strain SEBR 4211T, was isolated from an African saline oil-producing well. Cells stain Gram-positive, which was confirmed by electron microscopy observations. Strain SEBR 4211T was motile by means of one to four peritrichous flagella, had a G+C content of 43 mol% and grew optimally at 37 degrees C, pH 7.3, with 0 to 3% (w/v) NaCl. It utilized a limited number of carbohydrates (cellobiose, glucose, fructose, mannitol and ribose) and produced acetate, butyrate, CO2 and H2 as end products from glucose fermentation. It reduced thiosulfate to sulfide. In the presence of thiosulfate, a decrease in butyrate and an increase in acetate production was observed. Phylogenetically, strain SEBR 4211T was related to members of the low G+C Clostridiales order with Clostridium halophilum as the closest relative (16S rDNA sequence similarity of 90%). On the basis of phenotypic, genotypic and phylogenetic characteristics of the isolate, it is proposed to designate it as a new species of a new genus, Fusibacter gen. nov., as Fusibacter paucivorans sp. nov. The type strain is SEBR 4211T (= DSM 12116T).
International journal of systematic bacteriology 08/1999; 49 Pt 3:1141-7.
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ABSTRACT: A novel, asaccharolytic, amino-acid-degrading bacterium, designated strain GLU-3T, was isolated from an anaerobic lagoon of a dairy wastewater treatment plant. Strain GLU-3T stained Gram-negative and was an obligately anaerobic, non-spore-forming, slightly curved, rod-shaped bacterium (0.3 x 4.0-6.0 microns) which existed singly or in pairs. The DNA G+C content was 43 mol%. Optimum growth occurred at 35 degrees C and pH 7.5 on arginine with a generation time of 16 h. Good growth was obtained on arginine, histidine, threonine and glycine. Acetate was the end-product formed from all these substrates, but in addition, a trace of formate was detected from arginine and histidine, and ornithine was produced from arginine. Strain GLU-3T grew slowly on glutamate and produced acetate, carbon dioxide, formate, hydrogen and traces of propionate as the end-products. In syntrophic association with Methanobacterium formicicum, strain GLU-3T oxidized arginine, histidine and glutamate to give propionate as the major product; acetate, carbon dioxide and methane were also produced. Strain GLU-3T did not degrade alanine and the branched-chain amino acids valine, leucine and isoleucine either in pure culture or in association with M. formicicum. The nearest phylogenetic relative of strain GLU-3T was the thermophile Selenomonas acidaminovorans (similarity value of 89.5%). As strain GLU-3T is phylogenetically, physiologically and genotypically different from other amino-acid-degrading genera, it is proposed that it should be designated a new species of a new genus Aminomonas paucivorans gen. nov., sp. nov. (DSM 12260T).
International journal of systematic bacteriology 08/1999; 49 Pt 3:975-82.
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ABSTRACT: A mesophilic strain of sulfate-reducing bacterium, designated ALA-3T (T = type strain), was isolated from an anaerobic lagoon of a dairy wastewater treatment plant. The curved, Gram-negative, non-sporeforming cells (0.2 x 3.0-4.0 microns) existed singly or in chains, and were motile by single polar flagella. Optimum growth occurred at 35 degrees C and pH 7.5 on a medium containing lactate and sulfate. Thiosulfate or sulfite but not elemental sulfur, nitrate, or fumarate could also replace sulfate as an electron acceptor. Formate, alanine, aspartate, leucine, isoleucine, valine, and methionine, H2/CO2 and ethanol also served as electron donors with sulfate as an electron acceptor. Pyruvate, casamino acids, peptone, serine, glycine, cysteine and threonine were fermented. Sulfite and thiosulfate were disproportionated to sulfate and sulfide. The G + C content of the DNA was 66 mol % G + C. Phylogenetic analysis revealed that Desulfovibrio africanus was the nearest relative (similarity of 89%). Strain ALA-3T is physiologically and phylogenetically different from other Desulfovibrio species, and is designated Desulfovibrio aminophilus sp. nov. (DSM 12254).
Systematic and Applied Microbiology 01/1999; 21(4):498-504. · 3.37 Impact Factor
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ABSTRACT: A new gram-negative, non-sporulating, mesophilic, amino acid fermenting bacterium, designated strain ALA-1(T) (T = type strain), was isolated from an anaerobic lagoon of a dairy wastewater treatment plant. The strain is curved (3-4 microm x 0.2-0.3 microm) and occurs singly or in pairs. Optimum growth occurs at 37 degrees C and pH 7.3. The G+C content of the DNA is 46 mol %. The strain requires yeast extract for growth, grows poorly on casamino acids, peptones, cysteine, and alpha-ketoglutarate, but readily grows on serine, threonine, glycine and pyruvate. When cocultured with the hydrogenotrophic methanogen Methanobacterium formicicum, strain ALA-1(T) oxidized alanine, glutamate, leucine, isoleucine, valine, aspartate, and methionine. Phylogenetic analysis revealed that it forms a distinct and independent line of descent in the vicinity of Dethiosulfovibrio peptidovorans, Dictyoglomus thermophilum, and Anaerobaculum thermoterrenum which are members of the low G+C containing gram-positive bacteria. The phylogenetic results concur with the phenotypic and genomic data which reveal that it is a novel strain. Based on these findings, we designate strain ALA-1(T) as Aminobacterium colombiense (DSM 12261) gen. nov., sp. nov.
Anaerobe 11/1998; 4(5):241-50. · 2.41 Impact Factor
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ABSTRACT: Two irregular coccoid methanogens designated SEBR 4845T and FR1T were isolated from an oilfield in Alsace, France. Strain SEBR 4845T (T = type strain) is a hydrogenotrophic halotolerant methanogen, which grows optimally at 5% NaCI (w/v) and tolerates up to 12% NaCI. It does not use methylated compounds and therefore cannot be ascribed to any of the known genera of the halophilic methylotrophic methanogens. It differs from hydrogenotrophic members of the orders Methanococcales and Methanomicrobia les in the NaCI growth range (0-12% NaCI), which is the widest reported to data for any hydrogenotrophic methanogen. 16S rRNA gene sequence analysis indicated that strain SEBR 4845T is a novel isolate for which a new genus is proposed, Methanocalculus halotolerans gen. nov., sp. nov. (= OCM470T) that might be indigenous to the oilfield ecosystem. Strain FR1T (=OCM 471) is a moderately halophilic methanogen which growths optimally at 10% NaCI and tolerates up to 20% NaCI. It grows on trimethylamine and methanol as carbon and energy sources. The G+C content of its DNA is 43 mol%. It is therefore phenotypically and genotypically related to members of the genus Methanohalophilus. This report provides evidence that methylotrophic and hydrogenotrophic, but not aceticlastic methanogens are present in a saline subsurface oilfield environment, as already observed in surface saline to hypersaline environments.
International journal of systematic bacteriology 08/1998; 48 Pt 3:821-8.
