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Kenneth M Noll - One of the best experts on this subject based on the ideXlab platform.
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Genes for the Major Structural Components of Thermotogales Species ’ Togas Revealed by Proteomic and Evolutionary Analyses of OmpA and OmpB
2016Co-Authors: A K. Petrus, Kristen S Swithers, Peter J Gogarten, Chaman Ranjit, Heather M. Brewer, Ljiljana Pasa-tolic, Kenneth M NollAbstract:The unifying structural characteristic of members of the bacterial order Thermotogales is their toga, an unusual cell envelope that includes a loose-fitting sheath around each cell. Only two toga-associated structural proteins have been purified and characterized in Thermotoga maritima: the anchor protein OmpA1 (or Ompa) and the porin OmpB (or Ompb). The gene encoding OmpA1 (ompA1) was cloned and sequenced and later assigned to TM0477 in the genome sequence, but because no peptide sequence was available for OmpB, its gene (ompB) was not annotated. We identified six porin candidates in the genome sequence of T. maritima. Of these candidates, only one, encoded by TM0476, has all the characteristics reported for OmpB and characteristics expected of a porin including predominant b-sheet structure, a carboxy terminus porin anchoring motif, and a porin-specific amino acid composition. We highly enriched a toga fraction of cells for OmpB by sucrose gradient centrifugation and hydroxyapatite chromatography and analyzed it by LC/MS/MS. We found that the only porin candidate that it contained was the TM0476 product. This cell fraction also had b-sheet character as determined by circular dichroism, consistent with its enrichment for OmpB. We conclude that TM0476 encodes OmpB. A phylogenetic analysis of OmpB found orthologs encoded in syntenic locations in the genomes of all but two Thermotogales species. Those without orthologs have putative isofunctional genes in their place. Phylogenetic analyses of OmpA1 revealed that each species of the Thermotogales has one or two OmpA homologs. T. maritima has two OmpA homologs, encoded b
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biohydrogenesis in the Thermotogales
2014Co-Authors: Robert M. Kelly, Paul H Blum, Kenneth M NollAbstract:The production and consumption of molecular hydrogen drives the physiology and bioenergetics of many microorganisms in hydrothermal environments. As such, the potential of these microorganisms as model systems to probe fundamental issues related to biohydrogen production merits consideration. It is important to understand how carbon/energy sources relate to the disposition of reducing power and, ultimately, the formation of molecular hydrogen by high temperature microorganisms. This project focused on bacteria in the thermophilic order Thermotogales, fermentative anaerobes that produce H2 from simple and complex carbohydrates. The major thrusts of the project are summarized in the Objectives listed below: OBJECTIVE 1: Examine the regulation of substrate catabolic proteins and pathways as this relates to carbon partitioning, disposition of reducing power, and H2 generation in Thermotoga maritima. OBJECTIVE 2: Apply classical genetics and develop molecular genetic tools for Thermotoga species to dissect catabolic and regulatory pathways related to sugar metabolism and H2 evolution. OBJECTIVE 3: Thermotogales biodiversity arises from adaptive specialization that expands on a conserved minimal genome; physiological characterization of selected novel traits will be done to expand understanding of biohydrogenesis. Four species within the genus Thermotoga were examined to understand similarities and differences in the mechanisms by which simple and complexmore » carbohydrates were utilized and converted to molecular hydrogen. Although the core genome of these four species represented 75% of open reading frames (ORFs), there were significant differences in carbohydrate utilization patterns. New ABC transporters were identified within the Thermotogales through genomic and biochemical analysis. Molecular genetics tools were developed to examine Thermotoga maritima physiology. Cell lines were created in which both H2 and acetate levels were elevated on a per cell basis relative to the wild type, while lactate remained undetectable. Genome resequencing indicated that the primary genetic target for these phenotypic changes was the ATP binding component of a maltose ABC transporter. High temperature anaerobic [14C]-maltose transport assays demonstrated maltose uptake was reduced in the H2 overproducing cell lines. This suggested normal rates of maltose transport in the wild type organism lead to a metabolic imbalance that limited H2 synthesis. The microbial ecology of T. maritima was examined through functional genomics experiments. Under low nutrient conditions, T. maritima was observed to produce a range of putative peptides, some of which were related to α-carbon cyclic peptides produced by Bacillus subtilus. Finally, the role of ‘toga’ in these novel microorganisms was shown to involve association with insoluble growth substrates. The ‘toga’ distends from the cytoplasmic membrane-enclosed portion of the cells as they enter the late exponential/stationary phase of growth. Some of the genes encoding toga-associated proteins were up-regulated during this phase of growth and the distension is caused by continued growth of the toga, and not shrinkage of the cytoplasmic aspect of the cells. This increase in cell surface area may have selective value to provide a larger anchor for polysaccharide hydrolytic enzymes during a time of nutritional stress. This project led to many interesting insights about the Thermotogales that have both scientific and technological implications. Ongoing work will leverage these developments to further elucidate many interesting features of these novel microorganisms.« less
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vitamin b12 synthesis and salvage pathways were acquired by horizontal gene transfer to the Thermotogales
Genome Biology and Evolution, 2012Co-Authors: Kristen S Swithers, Camilla L Nesbø, Kenneth M Noll, Amanda K Petrus, Michael A Secinaro, Peter J Gogarten, Nicholas C ButzinAbstract:The availability of genome sequences of Thermotogales species from across the order allows an examination of the evolutionary origins of phenotypic characteristics in this lineage. Several studies have shown that the Thermotogales have acquired large numbers of genes from distantly related lineages, particularly Firmicutes and Archaea. Here, we report the finding that some Thermotogales acquired the ability to synthesize vitamin B12 by acquiring the requisite genes from these distant lineages. Thermosipho species, uniquely among the Thermotogales, contain genes that encode the means to synthesize vitamin B12 de novo from glutamate. These genes are split into two gene clusters: the corrinoid synthesis gene cluster, that is unique to the Thermosipho and the cobinamide salvage gene cluster. The corrinoid synthesis cluster was acquired from the Firmicutes lineage, whereas the salvage pathway is an amalgam of bacteria- and archaea-derived proteins. The cobinamide salvage gene cluster has a patchy distribution among Thermotogales species, and ancestral state reconstruction suggests that this pathway was present in the common Thermotogales ancestor. We show that Thermosipho africanus can grow in the absence of vitamin B 12, so its de novo pathway is functional. We detected vitamin B12 in the extracts of T. africanus cells to verify the synthetic pathway. Genes in T. africanus with apparent B12 riboswitches were found to be down-regulated in the presence of vitamin B12 consistent with their roles in B12 synthesis and cobinamide salvage.
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genes for the major structural components of Thermotogales species togas revealed by proteomic and evolutionary analyses of ompa and ompb homologs
PLOS ONE, 2012Co-Authors: Amanda K Petrus, Kristen S Swithers, Peter J Gogarten, Chaman Ranjit, Heather M. Brewer, Ljiljana Pasatolic, Kenneth M NollAbstract:The unifying structural characteristic of members of the bacterial order Thermotogales is their toga, an unusual cell envelope that includes a loose-fitting sheath around each cell. Only two toga-associated structural proteins have been purified and characterized in Thermotoga maritima: the anchor protein OmpA1 (or Ompa) and the porin OmpB (or Ompb). The gene encoding OmpA1 (ompA1) was cloned and sequenced and later assigned to TM0477 in the genome sequence, but because no peptide sequence was available for OmpB, its gene (ompB) was not annotated. We identified six porin candidates in the genome sequence of T. maritima. Of these candidates, only one, encoded by TM0476, has all the characteristics reported for OmpB and characteristics expected of a porin including predominant b-sheet structure, a carboxy terminus porin anchoring motif, and a porin-specific amino acid composition. We highly enriched a toga fraction of cells for OmpB by sucrose gradient centrifugation and hydroxyapatite chromatography and analyzed it by LC/MS/MS. We found that the only porin candidate that it contained was the TM0476 product. This cell fraction also had b-sheet character as determined by circular dichroism, consistent with its enrichment for OmpB. We conclude that TM0476 encodes OmpB. A phylogenetic analysis of OmpB found orthologsmore » encoded in syntenic locations in the genomes of all but two Thermotogales species. Those without orthologs have putative isofunctional genes in their place. Phylogenetic analyses of OmpA1 revealed that each species of the Thermotogales has one or two OmpA homologs. T. maritima has two OmpA homologs, encoded by ompA1 (TM0477) and ompA2 (TM1729), both of which were found in the toga protein-enriched cell extracts. These annotations of the genes encoding toga structural proteins will guide future examinations of the structure and function of this unusual lineage-defining cell sheath.« less
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Mesotoga prima gen. nov., sp. nov., the first described mesophilic species of the Thermotogales
Extremophiles, 2012Co-Authors: Camilla L Nesbø, W Ford Doolittle, Marlena Dlutek, Amanda K Petrus, Danielle M. Bradnan, Abigail Adebusuyi, Julia Foght, Kenneth M NollAbstract:A novel mesophilic member of the Thermotogales, strain MesG1.Ag.4.2, was isolated from sediments from Baltimore Harbor, MD, USA. The strain grew optimally at 37 °C with a doubling time of 16.5 h on xylose. Carbohydrates and proteinaceous compounds supported growth and pentoses were preferred over hexoses. The strain was strictly anaerobic and growth was slightly stimulated by thiosulfate, sulfite, and elemental sulfur. The G + C content of its genomic DNA was 45.3 mol%. Strain MesG1.Ag.4.2 and Kosmotoga olearia lipids were analyzed. Strain MesG1.Ag.4.2 contained no long-chain dicarboxylic acids and its major phospholipid was lyso-phosphatidylserine. Long-chain dicarboxylic acids were found in K. olearia and its major phospholipid was cardiolipin, a lipid not yet reported in Thermotogales species. Phylogenetic analyses of its two 16S rRNA genes placed strain MesG1.Ag.4.2 within the bacterial order Thermotogales. Based on the phylogenetic analyses and its low optimal growth temperature, it is proposed that the strain represents a novel species of a new genus within the family Thermotogaceae, order Thermotogales. The name Mesotoga prima gen. nov., sp. nov. is proposed. The type strain of M. prima is MesG1.Ag.4.2 (= DSM 24739 = ATCC BAA-2239).
Bernard Ollivier - One of the best experts on this subject based on the ideXlab platform.
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Towards a congruent reclassification and nomenclature of the thermophilic species of the genus Pseudothermotoga within the order Thermotogales
Systematic and Applied Microbiology, 2018Co-Authors: Hassiba Belahbib, Bernard Ollivier, Alain Dolla, Marielaure Fardeau, Zarath Summers, Manon Joseph, Christian Tamburini, Fabrice ArmougomAbstract:The phylum Thermotogae gathers thermophilic, hyperthermophic, mesophilic, and thermo-acidophilic anaerobic bacteria that are mostly originated from geothermally heated environments. The metabolic and phenotypic properties harbored by the Thermotogae species questions the evolutionary events driving the emergence of this early branch of the universal tree of life. Recent reshaping of the Thermotogae taxonomy has led to the description of a new genus, Pseudothermotoga, a sister group of the genus Thermotoga within the order Thermotogales. Comparative genomics of both Pseudothermotoga and Ther-motoga spp., including 16S-rRNA-based phylogenetic, pan-genomic analysis as well as signature indel conservation, provided evidence that Thermotoga caldifontis and Thermotoga profunda species should be reclassified within the genus Pseudothermotoga and renamed as Pseudothermotoga caldifontis comb. nov. (type strain = AZM44c09 T) and Pseudothermotoga profunda comb. nov. (type strain = AZM34c06 T), respectively. In addition, based upon whole-genome relatedness indices and DNA-DNA Hybridization results, the reclassification of Pseudothermotoga lettingae and Pseudothermotoga subterranea as latter heterotypic synonyms of Pseudothermotoga elfii is proposed. Finally, potential genetic elements resulting from the distinct evolutionary story of the Thermotoga and Pseudothermotoga clades are discussed.
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Draft genome sequence of Mesotoga strain PhosAC3, a mesophilic member of the bacterial order Thermotogales, isolated from a digestor treating phosphogypsum in Tunisia
Standards in Genomic Sciences, 2015Co-Authors: Wajdi Ben Hania, Bernard Ollivier, Alain Dolla, Anne Postec, Céline Brochier-armanet, M Hamdi, Marielaure Fardeau, Khaled Fadhlaoui, Cecile Persillon, Jean Le MerAbstract:Mesotoga strain PhosAc3 was the first mesophilic cultivated member of the order Thermotogales. This genus currently contain two described species, M. prima and M. infera. Strain PhosAc3, isolated from a Tunisian digestor treating phosphogypsum, is phylogenetically closely related to M. prima strain MesG1.Ag.4.2(T). Strain PhosAc3 has a genome of 3.1 Mb with a G + C content of 45.2%. It contains 3,051 protein-coding genes of which 74.6% have their best reciprocal BLAST hit in the genome of the type species, strain MesG1.Ag.4.2(T). For this reason we propose to assign strain PhosAc3 as a novel ecotype of the Mesotoga prima species. However, in contrast with the M. prima type strain, (i) it does not ferment sugars but uses them only in the presence of elemental sulfur as terminal electron acceptor, (ii) it produces only acetate and CO2 from sugars, whereas strain MesG1.Ag.4.2(T) produces acetate, butyrate, isobutyrate, isovalerate, 2-methyl-butyrate and (iii) sulfides are also end products of the elemental sulfur reduction in theses growth conditions.
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Members of the order Thermotogales: from microbiology to hydrogen production.
2014Co-Authors: Martina Cappelletti, Anne Postec, Davide Zannoni, Bernard OllivierAbstract:Members of the deep-branching order Thermotogales are widespread in various terrestrial, submarine and subterrestrial extreme environments. This bacterial order included both thermophilic and hyperthermophilic anaerobic microorganisms so far pertaining to 10 genera. It is only recently (2011) that cultivation of a mesophilic member of this order belonging to a novel genus Mesotoga, has been successful. All members, with the exception of Mesotoga spp., are recognized as high hydrogen producers having possible applications in biotechnology with a peculiar emphasis for members of the genus Thermotoga (e.g. T. maritima and T. neapolitana). The ecology, phylogeny and metabolism linked to hydrogen production of these bacteria, are reviewed.
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members of the order Thermotogales from microbiology to hydrogen production
2014Co-Authors: Martina Cappelletti, Anne Postec, Davide Zannoni, Bernard OllivierAbstract:Members of the deep-branching order Thermotogales are widespread in various terrestrial, submarine and subterrestrial extreme environments. This bacterial order included both thermophilic and hyperthermophilic anaerobic microorganisms so far pertaining to ten genera. It is only recently (2011) that cultivation of a mesophilic member of this order belonging to a novel genus, Mesotoga, has been successful. All members, with the exception of Mesotoga spp., are recognized as high hydrogen producers having possible applications in biotechnology with a peculiar emphasis for members of the genus Thermotoga (e.g. T. maritima and T. neapolitana). The ecology, phylogeny and metabolism linked to hydrogen production of these bacteria, are reviewed.
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Mesotoga infera sp. nov., a mesophilic member of the order Thermotogales, isolated from an underground gas storage aquifer.
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Wajdi Ben Hania, Bernard Ollivier, Anne Postec, T Aüllo, A Ranchou-peyruse, Gaël Erauso, Céline Brochier-armanet, M Hamdi, S Saint-laurent, Michel MagotAbstract:Strain VNs100(T), a novel mesophilic, anaerobic, rod-coccoid-shaped bacterium, having a sheath-like outer structure (toga), was isolated from a water sample collected in the area of an underground gas storage aquifer. It was non-motile with cells appearing singly (2-4 µm long × 1-2 µm wide), in pairs or as long chains and stained Gram-negative. Strain VNs100(T) was heterotrophic, able to use arabinose, cellobiose, fructose, galactose, glucose, lactose, lactate, mannose, maltose, raffinose, ribose, sucrose and xylose as energy sources only in the presence of elemental sulfur as terminal electron acceptor. Acetate, CO2 and sulfide were the end products of sugar metabolism. Hydrogen was not detected. Elemental sulfur, but not thiosulfate, sulfate or sulfite, were reduced to sulfide. Strain VNs100(T) grew at temperatures between 30 and 50 °C (optimum 45 °C), at pH values between 6.2 and 7.9 (optimum 7.3-7.5) and at NaCl concentrations between 0 and 15 g l(-1) (optimum 2 g l(-1)). The DNA G+C content was 47.5 mol%. The main cellular fatty acid was C16 : 0. Phylogenetic analysis of the small subunit rRNA gene sequence indicated that strain VNs100(T) had as its closest relatives 'Mesotoga sulfurireducens' (97.1 % similarity) and Mesotoga prima (similarity of 97.1 % and 97.7 % with each of its two genes, respectively) within the order Thermotogales. Hybridization between strain VNS100(T) and 'M. sulfurireducens' and between strain VNS100(T) and M. prima showed 12.9 % and 20.6 % relatedness, respectively. Based on phenotypic, phylogenetic and taxonomic characteristics, strain VNs100(T) is proposed as a representative of a novel species of the genus Mesotoga in the family Thermotogaceae, order Thermotogales. The name Mesotoga infera sp. nov. is proposed. The type strain is VNs100(T) (= DSM 25546(T) = JCM 18154(T)).
Camilla L Nesbø - One of the best experts on this subject based on the ideXlab platform.
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‘Ménage à trois’: a selfish genetic element uses a virus to propagate within Thermotogales
Applied and Environmental Microbiology, 2015Co-Authors: Julien Lossouarn, Camilla L Nesbø, Olga Zhaxybayeva, Coraline Mercier, Milo S. Johnson, Rhianna Charchuck, Julien Farasin, Nadège Bienvenu, Anne-claire Baudoux, Grégoire MichoudAbstract:Prokaryotic viruses play a major role in the microbial ecology and evolution. However, the virosphere associated with deep-sea hydrothermal ecosystems remains largely unexplored. Numerous instances of lateral gene transfer have contributed to the complex and incongruent evolutionary history of Thermotogales, an order well represented in deep-sea hydrothermal vents. The presence of clustered regularly interspaced short palindromic repeats (CRISPR) loci has been reported in all Thermotogales genomes, suggesting that these bacteria have been exposed to viral infections that could have mediated gene exchange. In this study, we isolated and characterized the first virus infecting bacteria from the order Thermotogales, Marinitoga piezophila virus 1 (MPV1). The host, Marinitoga piezophila is a thermophilic, anaerobic and piezophilic bacterium isolated from a deep-sea hydrothermal chimney. MPV1 is a temperate Siphoviridae-like virus with a 43.7 kb genome. Surprisingly, we found that MPV1 virions carry not only the viral DNA but preferentially package a plasmid of 13.3 kb (pMP1) also carried by M. piezophila. This ‘ménage à trois’ highlights potential relevance of selfish genetic elements in facilitating lateral gene transfer in the deep-sea biosphere.
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menage a trois a selfish genetic element uses a virus to propagate within Thermotogales
Applied and Environmental Microbiology, 2015Co-Authors: Julien Lossouarn, Camilla L Nesbø, Olga Zhaxybayeva, Coraline Mercier, Milo S. Johnson, Rhianna Charchuck, Julien Farasin, Nadège Bienvenu, Anne-claire Baudoux, Grégoire MichoudAbstract:Prokaryotic viruses play a major role in the microbial ecology and evolution. However, the virosphere associated with deep-sea hydrothermal ecosystems remains largely unexplored. Numerous instances of lateral gene transfer have contributed to the complex and incongruent evolutionary history of Thermotogales, an order well represented in deep-sea hydrothermal vents. The presence of clustered regularly interspaced short palindromic repeats (CRISPR) loci has been reported in all Thermotogales genomes, suggesting that these bacteria have been exposed to viral infections that could have mediated gene exchange. In this study, we isolated and characterized the first virus infecting bacteria from the order Thermotogales, Marinitoga piezophila virus 1 (MPV1). The host, Marinitoga piezophila is a thermophilic, anaerobic and piezophilic bacterium isolated from a deep-sea hydrothermal chimney. MPV1 is a temperate Siphoviridae-like virus with a 43.7 kb genome. Surprisingly, we found that MPV1 virions carry not only the viral DNA but preferentially package a plasmid of 13.3 kb (pMP1) also carried by M. piezophila. This ‘menage a trois’ highlights potential relevance of selfish genetic elements in facilitating lateral gene transfer in the deep-sea biosphere.
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vitamin b12 synthesis and salvage pathways were acquired by horizontal gene transfer to the Thermotogales
Genome Biology and Evolution, 2012Co-Authors: Kristen S Swithers, Camilla L Nesbø, Kenneth M Noll, Amanda K Petrus, Michael A Secinaro, Peter J Gogarten, Nicholas C ButzinAbstract:The availability of genome sequences of Thermotogales species from across the order allows an examination of the evolutionary origins of phenotypic characteristics in this lineage. Several studies have shown that the Thermotogales have acquired large numbers of genes from distantly related lineages, particularly Firmicutes and Archaea. Here, we report the finding that some Thermotogales acquired the ability to synthesize vitamin B12 by acquiring the requisite genes from these distant lineages. Thermosipho species, uniquely among the Thermotogales, contain genes that encode the means to synthesize vitamin B12 de novo from glutamate. These genes are split into two gene clusters: the corrinoid synthesis gene cluster, that is unique to the Thermosipho and the cobinamide salvage gene cluster. The corrinoid synthesis cluster was acquired from the Firmicutes lineage, whereas the salvage pathway is an amalgam of bacteria- and archaea-derived proteins. The cobinamide salvage gene cluster has a patchy distribution among Thermotogales species, and ancestral state reconstruction suggests that this pathway was present in the common Thermotogales ancestor. We show that Thermosipho africanus can grow in the absence of vitamin B 12, so its de novo pathway is functional. We detected vitamin B12 in the extracts of T. africanus cells to verify the synthetic pathway. Genes in T. africanus with apparent B12 riboswitches were found to be down-regulated in the presence of vitamin B12 consistent with their roles in B12 synthesis and cobinamide salvage.
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Mesotoga prima gen. nov., sp. nov., the first described mesophilic species of the Thermotogales
Extremophiles, 2012Co-Authors: Camilla L Nesbø, W Ford Doolittle, Marlena Dlutek, Amanda K Petrus, Danielle M. Bradnan, Abigail Adebusuyi, Julia Foght, Kenneth M NollAbstract:A novel mesophilic member of the Thermotogales, strain MesG1.Ag.4.2, was isolated from sediments from Baltimore Harbor, MD, USA. The strain grew optimally at 37 °C with a doubling time of 16.5 h on xylose. Carbohydrates and proteinaceous compounds supported growth and pentoses were preferred over hexoses. The strain was strictly anaerobic and growth was slightly stimulated by thiosulfate, sulfite, and elemental sulfur. The G + C content of its genomic DNA was 45.3 mol%. Strain MesG1.Ag.4.2 and Kosmotoga olearia lipids were analyzed. Strain MesG1.Ag.4.2 contained no long-chain dicarboxylic acids and its major phospholipid was lyso-phosphatidylserine. Long-chain dicarboxylic acids were found in K. olearia and its major phospholipid was cardiolipin, a lipid not yet reported in Thermotogales species. Phylogenetic analyses of its two 16S rRNA genes placed strain MesG1.Ag.4.2 within the bacterial order Thermotogales. Based on the phylogenetic analyses and its low optimal growth temperature, it is proposed that the strain represents a novel species of a new genus within the family Thermotogaceae, order Thermotogales. The name Mesotoga prima gen. nov., sp. nov. is proposed. The type strain of M. prima is MesG1.Ag.4.2 (= DSM 24739 = ATCC BAA-2239).
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searching for mesophilic Thermotogales bacteria mesotogas in the wild
Applied and Environmental Microbiology, 2010Co-Authors: Camilla L Nesbø, Rajkumari Kumaraswamy, Marlena Dlutek, Ford W Doolittle, Julia M FoghtAbstract:All cultivated Thermotogales are thermophiles or hyperthermophiles. However, optimized 16S rRNA primers successfully amplified Thermotogales sequences from temperate hydrocarbon-impacted sites, mesothermic oil reservoirs, and enrichment cultures incubated at <46 degrees C. We conclude that distinct Thermotogales lineages commonly inhabit low-temperature environments but may be underreported, likely due to "universal" 16S rRNA gene primer bias.
Michel Magot - One of the best experts on this subject based on the ideXlab platform.
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Mesotoga infera sp. nov., a mesophilic member of the order Thermotogales, isolated from an underground gas storage aquifer.
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Wajdi Ben Hania, Bernard Ollivier, Anne Postec, T Aüllo, A Ranchou-peyruse, Gaël Erauso, Céline Brochier-armanet, M Hamdi, S Saint-laurent, Michel MagotAbstract:Strain VNs100(T), a novel mesophilic, anaerobic, rod-coccoid-shaped bacterium, having a sheath-like outer structure (toga), was isolated from a water sample collected in the area of an underground gas storage aquifer. It was non-motile with cells appearing singly (2-4 µm long × 1-2 µm wide), in pairs or as long chains and stained Gram-negative. Strain VNs100(T) was heterotrophic, able to use arabinose, cellobiose, fructose, galactose, glucose, lactose, lactate, mannose, maltose, raffinose, ribose, sucrose and xylose as energy sources only in the presence of elemental sulfur as terminal electron acceptor. Acetate, CO2 and sulfide were the end products of sugar metabolism. Hydrogen was not detected. Elemental sulfur, but not thiosulfate, sulfate or sulfite, were reduced to sulfide. Strain VNs100(T) grew at temperatures between 30 and 50 °C (optimum 45 °C), at pH values between 6.2 and 7.9 (optimum 7.3-7.5) and at NaCl concentrations between 0 and 15 g l(-1) (optimum 2 g l(-1)). The DNA G+C content was 47.5 mol%. The main cellular fatty acid was C16 : 0. Phylogenetic analysis of the small subunit rRNA gene sequence indicated that strain VNs100(T) had as its closest relatives 'Mesotoga sulfurireducens' (97.1 % similarity) and Mesotoga prima (similarity of 97.1 % and 97.7 % with each of its two genes, respectively) within the order Thermotogales. Hybridization between strain VNS100(T) and 'M. sulfurireducens' and between strain VNS100(T) and M. prima showed 12.9 % and 20.6 % relatedness, respectively. Based on phenotypic, phylogenetic and taxonomic characteristics, strain VNs100(T) is proposed as a representative of a novel species of the genus Mesotoga in the family Thermotogaceae, order Thermotogales. The name Mesotoga infera sp. nov. is proposed. The type strain is VNs100(T) (= DSM 25546(T) = JCM 18154(T)).
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Mesotoga infera sp. nov., a novel mesophilic member of the order Thermotogales, isolated from an underground gas storage in France
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: W Ben-hamia, Bernard Ollivier, Anne Postec, T Aüllo, A Ranchou-peyruse, Gaël Erauso, Céline Brochier-armanet, M Hamdi, S Saint-laurent, Michel MagotAbstract:Strain VNs100T, a novel mesophilic anaerobic rod-cocoid-shaped bacterium, having a sheath-like outer structure (toga) was isolated from a water sample collected in the area of underground gas storage. It was non-motile with cells Appearing singly (2-4 μm long x 1-2 μm wide), in pairs, or as long chains and stained Gram-negative. Strain VNs100T was heterotrophic, able to use arabinose, cellobiose, fructose, galactose, glucose, lactose, lactate, mannose, maltose, raffinose, ribose, sucrose and xylose as energy sources only in the presence of elemental sulfur as terminal electron acceptor. Acetate, CO2 and sulfide were the end-products of sugar metabolism. Hydrogen was not detected. Elemental sulfur, but not thiosulfate, sulfate and sulfite, were reduced into sulfide. It grew at temperatures between 30°C and 50°C (optimum 45°C), at pH between 6.2 and 7.9 (optimum 7.3-7.5) and at NaCl concentrations between 0 and 15 g.L-1 (optimum 2 g.L-1). The DNA G+C content was 47.5 mol%. The main cellular fatty acid was C16:0. Phylogenetic analysis of the small-subunit (SSU) ribosomal RNA (rRNA) gene sequence indicated that strain VNs100T had as its closest relatives 'Mesotoga sulfurireducens' (97.1 % similarity) and Mesotoga prima (similarity of 97.1 % and 97.7 % with each of its two genes respectively) within the order Thermotogales. Hybridization between strain VNS100T and 'Mesotoga sulfurireducens' and between strain VNS100T and Mesotoga prima is 12.9% and 20.6 %, respectively. Based on phenotypic, phylogenetic and taxonomic characteristics, strain VNs100T is proposed as a novel species of genus Mesotoga within the family Thermotogaceae, order Thermotogales. The name Mesotoga infera, sp. nov. is proposed. The type strain is VNs100T (= DSM 25546 = JCM 18154).
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thiosulfate reduction an important physiological feature shared by members of the order Thermotogales
Applied and Environmental Microbiology, 1995Co-Authors: Gilles Ravot, Bernard Ollivier, Michel Magot, Bharat K C Patel, J L Crolet, Marielaure Fardeau, Jeanlouis GarciaAbstract:Several members of the order Thermotogales in the domain Bacteria, viz., Thermotoga neapolitana, Thermotoga maritima, Thermosipho africanus, Fervidobacterium islandicum, and Thermotoga strain SEBR 2665, an isolate from an oil well, reduced thiosulfate to sulfide. This reductive process enhanced cellular yields and growth rates of all the members but was more significant with the two hyperthermophiles T. neapolitana and T. maritima. This is the first report of such an occurrence in this group of thermophilic and hyperthermophilic anaerobic bacteria. The results suggest that thiosulfate reduction is important in the geochemical cycling of sulfur in anaerobic thermal environments such as the slightly acidic and neutral-pH volcanic hot springs and oil reservoirs.
Hui Zhang - One of the best experts on this subject based on the ideXlab platform.
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Thermococcoides shengliensis gen. nov., sp. nov., a new member of the order Thermotogales isolated from oil-production fluid.
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Yixiao Feng, Lei Cheng, Xiaoxia Zhang, Yu Deng, Hui ZhangAbstract:A novel thermophilic, strictly anaerobic, heterotrophic bacterium, strain 2SM-2T, was isolated from the Shengli oilfield, China. This organism was identified as a member of the order Thermotogales on the basis of its 16S rRNA gene sequence and the presence of an external membranous toga-like structure. Cells stained Gram-negative, were non-motile, appeared as irregular cocci 0.7–0.9 μm in diameter, and occurred in clusters of two to six cells, with cells located within a ballooning toga-like membrane. Its optimum temperature, pH and NaCl concentration for growth were 65 °C, 7.0 and 15 g l−1, respectively. Under the optimum growth conditions, the doubling time was approximately 105 min. Strain 2SM-2T fermented a variety of simple and complex substrates such as glucose, acetate, methanol, starch and peptone while reducing elemental sulfur, sulfate and thiosulfate. The end products identified during growth on glucose were acetate, lactate, l-alanine, H2 and CO2. The DNA G+C content of this organism was 36.4 mol%. The results of 16S rRNA gene-based sequence comparisons revealed that the strain represented a new lineage within the family Thermotogaceae of the order Thermotogales. Based on the phenotypic and phylogenetic characteristics, it is proposed that this organism represents a novel species in a new genus within the family Thermotogaceae, for which the name Thermococcoides shengliensis gen. nov., sp. nov. is proposed. The type strain is 2SM-2T (=ACCC 00496T=DSM 22460T).
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Thermococcoides shengliensis gen. nov., sp. nov., a new member of the order Thermotogales isolated from oil-production fluid.
International journal of systematic and evolutionary microbiology, 2009Co-Authors: Yixiao Feng, Lei Cheng, Xiaoxia Zhang, Yu Deng, Hui ZhangAbstract:A novel thermophilic, strictly anaerobic, heterotrophic bacterium, strain 2SM-2(T), was isolated from the Shengli oilfield, China. This organism was identified as a member of the order Thermotogales on the basis of its 16S rRNA gene sequence and the presence of an external membranous toga-like structure. Cells stained Gram-negative, were non-motile, appeared as irregular cocci 0.7-0.9 microm in diameter, and occurred in clusters of two to six cells, with cells located within a ballooning toga-like membrane. Its optimum temperature, pH and NaCl concentration for growth were 65 degrees C, 7.0 and 15 g l(-1), respectively. Under the optimum growth conditions, the doubling time was approximately 105 min. Strain 2SM-2(T) fermented a variety of simple and complex substrates such as glucose, acetate, methanol, starch and peptone while reducing elemental sulfur, sulfate and thiosulfate. The end products identified during growth on glucose were acetate, lactate, L-alanine, H2 and CO2. The DNA G+C content of this organism was 36.4 mol%. The results of 16S rRNA gene-based sequence comparisons revealed that the strain represented a new lineage within the family Thermotogaceae of the order Thermotogales. Based on the phenotypic and phylogenetic characteristics, it is proposed that this organism represents a novel species in a new genus within the family Thermotogaceae, for which the name Thermococcoides shengliensis gen. nov., sp. nov. is proposed. The type strain is 2SM-2(T) (=ACCC 00496(T)=DSM 22460(T)).
