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| Registros recuperados: 41 | |
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| Lossouarn, Julien; Nesbo, Camilla L.; Mercier, Coraline; Zhaxybayeva, Olga; Johnson, Milo S.; Charchuck, Rhianna; Farasin, Julien; Bienvenu, Nadege; Baudoux, Anne-claire; Michoud, Gregoire; Jebbar, Mohamed; Geslin, Claire. |
| 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... |
| Tipo: Text |
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| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00254/36483/36732.pdf |
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| L'Haridon, Stephane; Jiang, Lijing; Alain, Karine; Chalopin, Morgane; Rouxel, Ouafae; Beauverger, Mikael; Xu, Hongxiu; Shao, Zongze; Jebbar, Mohamed. |
| A novel strictly anaerobic thermophilic heterotrophic bacterium, strain SLHLJ1T, was isolated from a Pacific hydrothermal sediment. Cells were Gram-negative coccobacilli (approximately 1.0 × 0.6 μm) with a toga. It grew at temperatures between 33 and 78 °C (optimum 70 °C). Elemental sulphur and l-cystine stimulated its growth. It contained C16:0, C16:1 ω11c, C18:0 and C18:1 ω9c as major fatty acids (>5 %), 3 phospholipids and 2 glycolipids as polar lipids. Its DNA G+C content was 43.7 mol%. Phylogenetic analyses based on 16S rRNA gene sequences placed strain SLHLJ1T within the family Thermotogaceae. The novel isolate was most closely related to Kosmotoga arenicorallina (97.93 % 16S rRNA gene sequence similarity), K. olearia (92.43 %) and K. shengliensis... |
| Tipo: Text |
Palavras-chave: Thermotogales; Kosmotoga; Kosmotoga pacifica; Hydrothermal sediment. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00171/28204/26509.pdf |
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| Jebbar, Mohamed; Hickman-lewis, Keyron; Cavalazzi, Barbara; Taubner, Ruth-sophie; Rittmann, Simon K.-m. R.; Antunes, Andre. |
| The icy moons of the outer Solar System harbor potentially habitable environments for life, however, compared to the terrestrial biosphere, these environments are characterized by extremes in temperature, pressure, pH, and other physico-chemical conditions. Therefore, the search for life on these icy worlds is anchored on the study of terrestrial extreme environments (termed “analogue sites”), which harbor microorganisms at the frontiers of polyextremophily. These so-called extremophiles have been found in areas previously considered sterile: hot springs, hydrothermal vents, acidic or alkaline lakes, hypersaline environments, deep sea sediments, glaciers, and arid areas, amongst others. Such model systems and communities in extreme terrestrial environments... |
| Tipo: Text |
Palavras-chave: Extremophiles; Prokaryotes; Metabolism; Diversity; Adaptation; Space explorat. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00606/71771/70275.pdf |
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| Cao, Junwei; Maignien, Lois; Shao, Zongze; Alain, Karine; Jebbar, Mohamed. |
| The complete genome sequence of Desulfovibrio indicus J2(T), a member of the family Desulfovibrionaceae, consists of 3,966,573-bp in one contig and encodes 3,461 predicted genes, 5 noncoding RNAs, 3 rRNAs operons, and 52 tRNA-encoding genes. The genome is consistent with a heterotrophic, anaerobic lifestyle including the sulfate reduction pathway. |
| Tipo: Text |
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| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00601/71311/69740.pdf |
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| Martinez, N.; Michoud, Gregoire; Cario, A.; Ollivier, J.; Franzetti, B.; Jebbar, Mohamed; Oger, P.; Peters, J.. |
| Water and protein dynamics on a nanometer scale were measured by quasi-elastic neutron scattering in the piezophile archaeon Thermococcus barophilus and the closely related pressure-sensitive Thermococcus kodakarensis, at 0.1 and 40 MPa. We show that cells of the pressure sensitive organism exhibit higher intrinsic stability. Both the hydration water dynamics and the fast protein and lipid dynamics are reduced under pressure. In contrast, the proteome of T. barophilus is more pressure sensitive than that of T. kodakarensis. The diffusion coefficient of hydration water is reduced, while the fast protein and lipid dynamics are slightly enhanced with increasing pressure. These findings show that the coupling between hydration water and cellular constituents... |
| Tipo: Text |
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| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00350/46083/45742.pdf |
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| Thiel, Axel; Michoud, Gregoire; Moalic, Yann; Flament, Didier; Jebbar, Mohamed. |
| In this study, we developed a gene disruption system for Thermococcus barophilus using simvastatin for positive selection and 5-fluoroorotic acid (5-FOA) for negative selection or counterselection to obtain markerless deletion mutants using single-and double-crossover events. Disruption plasmids carrying flanking regions of each targeted gene were constructed and introduced by transformation into wild-type T. barophilus MP cells. Initially, a pyrF deletion mutant was obtained as a starting point for the construction of further markerless mutants. A deletion of the hisB gene was also constructed in the UBOCC-3256 (Delta pyrF) background, generating a strain (UBOCC-3260) that was auxotrophic for histidine. A functional pyrF or hisB allele from T. barophilus... |
| Tipo: Text |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00187/29818/28263.pdf |
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| Allioux, Maxime; Yvenou, Steven; Slobodkina, Galina; Slobodkin, Alexander; Shao, Zongze; Jebbar, Mohamed; Alain, Karine. |
| Marine hydrothermal systems are characterized by a pronounced biogeochemical sulfur cycle with the participation of sulfur-oxidizing, sulfate-reducing and sulfur-disproportionating microorganisms. The diversity and metabolism of sulfur disproportionators are studied to a much lesser extent compared with other microbial groups. Dissulfurirhabdus thermomarina SH388T is an anaerobic thermophilic bacterium isolated from a shallow sea hydrothermal vent. D. thermomarina is an obligate chemolithoautotroph able to grow by the disproportionation of sulfite and elemental sulfur. Here, we present the results of the sequencing and analysis of the high-quality draft genome of strain SH388T. The genome consists of a one circular chromosome of 2,461,642 base pairs, has a... |
| Tipo: Text |
Palavras-chave: Genome annotation; Dissulfurirhabdus; Shallow sea hydrothermal vents; Inorganic sulfur compound disproportionation. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00651/76270/77245.pdf |
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| Birien, Tiphaine; Thiel, Axel; Henneke, Ghislaine; Flament, Didier; Moalic, Yann; Jebbar, Mohamed. |
| A gene disruption system for Thermococcus barophilus was developed using simvastatin (HMG-CoA reductase encoding gene) for positive selection and 5-Fluoroorotic acid (5-FOA), a pyrF gene for negative selection. Multiple gene mutants were constructed with this system, which offers the possibility of complementation in trans, but produces many false positives (<80%). To significantly reduce the rate of false positives, we used another counterselective marker, 6-methylpurine (6-MP), a toxic analog of adenine developed in Thermococcus kodakarensis, consistently correlated with the TK0664 gene (encoding a hypoxanthine-guanine phosphoribosyl-transferase). We thus replaced pyrF by TK0664 on our suicide vector and tested T. barophilus strain sensitivity to 6-MP... |
| Tipo: Text |
Palavras-chave: Archaea; Piezophiles; Hyperthermophiles; Genetics; Gene deletion; Deep sea; Hydrothermal vents. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00425/53679/54523.pdf |
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| Cario, Anaïs; Jebbar, Mohamed; Thiel, Axel; Kervarec, Nelly; Oger, Phil M.. |
| The accumulation of mannosyl-glycerate (MG), the salinity stress response osmolyte of Thermococcales, was investigated as a function of hydrostatic pressure in Thermococcus barophilus strain MP, a hyperthermophilic, piezophilic archaeon isolated from the Snake Pit site (MAR), which grows optimally at 40 MPa. Strain MP accumulated MG primarily in response to salinity stress, but in contrast to other Thermococcales, MG was also accumulated in response to thermal stress. MG accumulation peaked for combined stresses. The accumulation of MG was drastically increased under sub-optimal hydrostatic pressure conditions, demonstrating that low pressure is perceived as a stress in this piezophile, and that the proteome of T. barophilus is low-pressure sensitive. MG... |
| Tipo: Text |
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| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00345/45570/45178.pdf |
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| Zeng, Xiang; Birrien, Jean-louis; Fouquet, Yves; Cherkashov, Georgy; Jebbar, Mohamed; Querellou, Joel; Oger, Philippe; Cambon-bonavita, Marie-anne; Xiao, Xiang; Prieur, Daniel. |
| A novel hydrothermal site was discovered in March 2007, on the mid-Atlantic ridge during the cruise 'Serpentine'. At a depth of 4100 m, the site 'Ashadze' is the deepest vent field known so far. Smoker samples were collected with the ROV 'Victor 6000' and processed in the laboratory for the enrichment of anaerobic heterotrophic microorganisms under high-temperature and high-hydrostatic pressure conditions. Strain CH1 was successfully isolated and assigned to the genus Pyrococcus, within the Euryarchaeota lineage within the Archaea domain. This organism grows within a temperature range of 80 to 108 degrees C and a pressure range of 20 to 120 MPa, with optima for 98 degrees C and 52 MPa respectively. Pyrococcus CH1 represents the first obligate piezophilic... |
| Tipo: Text |
Palavras-chave: Thermococcales; Extremophile; Deep sea hydrothermal vent; High hydrostatic pressure; Archaea. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6812.pdf |
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| Peters, Judith; Martinez, Nicolas; Michoud, Gregoire; Carlo, Anais; Franzetti, Bruno; Oger, Philippe; Jebbar, Mohamed. |
| The majority of the biosphere is a high pressure environment. Around 70% of the marine biosphere lies at depths below 1000 m, i.e. at pressures of 100 bars or higher. To survive in these environments, deep-biosphere organisms have adapted to life at high pressure. In vitro studies showed that the activity of certain proteins originating from deep-sea organisms is less affected by high pressure than that of enzymes from surface organisms [1-3]. However, the genetic and structural bases for this increased pressure resistance are still unknown. Elastic incoherent neutron scattering studies, which provide access to information about molecular dynamics, constitute a very promising approach to decipher the structural adaptation in proteins living under high... |
| Tipo: Text |
Palavras-chave: Neutron Scattering; Molecular Dynamics; High Pressure; Deep Sea Microbes. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00251/36186/34725.pdf |
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| Zapata-perez, Ruben; Garcia-saura, Antonio G.; Jebbar, Mohamed; Golyshin, Peter N.; Sanchez-ferrer, Alvaro. |
| Nicotinamidases catalyze the hydrolysis of the amide bond in nicotinamide (NAM) to produce ammonia and nicotinic acid (NA). These enzymes are an essential component of the NAD(+) salvage pathway and are implicated in the viability of several pathogenic organisms. Its absence in humans makes them a promising drug target. In addition, although they are key analytical biocatalysts for screening modulators in relevant biomedical enzymes, such as sirtuins and poly-ADP-ribosyltransferases, no commercial sources are available. Surprisingly, the finding of an affordable source of nicotinamidase from metagenomic libraries is hindered by the absence of a suitable and fast screening method. In this manuscript, we describe the development of two new whole-cell methods... |
| Tipo: Text |
Palavras-chave: Amidohydrolases; Nicotinamidase; Functional screening; Metagenome; Library; High-throughput screening assays. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00362/47269/47232.pdf |
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| Jan, Cyrielle; Petersen, Jillian M.; Werner, Johannes; Teeling, Hanno; Huang, Sixing; Gloeckner, Frank Oliver; Golyshina, Olga V.; Dubilier, Nicole; Golyshin, Peter N.; Jebbar, Mohamed; Cambon-bonavita, Marie-anne. |
| The gill chamber of deep-sea hydrothermal vent shrimp Rimicaris exoculata hosts a dense community of epibiotic bacteria dominated by filamentous Epsilonproteobacteria and Gammaproteobacteria. Using metagenomics on shrimp from the Rainbow hydrothermal vent field, we showed that both epibiont groups have the potential to grow autotrophically and oxidize reduced sulfur compounds or hydrogen with oxygen or nitrate. For carbon fixation, the Epsilonproteobacteria use the reductive tricarboxylic acid cycle, whereas the Gammaproteobacteria use the Calvin–Benson–Bassham cycle. Only the epsilonproteobacterial epibionts had the genes necessary for producing ammonium. This ability likely minimizes direct competition between epibionts and also broadens the spectrum of... |
| Tipo: Text |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00177/28874/28622.pdf |
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| L'Haridon, Stephane; Corre, Erwan; Guan, Yue; Vinu, Manikandan; La Cono, Violetta; Yakimov, Michail; Stingl, Ulrich; Toffin, Laurent; Jebbar, Mohamed. |
| We report here the complete genome sequence (2.08 Mb) of Methanohalophilus portucalensis strain FDF-1T, a halophilic methylotrophic methanogen isolated from the sediment of a saltern in Figeria da Foz, Portugal. The average nucleotide identity and DNA-DNA hybridization analyses show that Methanohalophilus mahii, M. halophilus, and M. portucalensis are three different species within the Methanosarcinaceae family. |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00420/53138/54102.pdf |
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| L’haridon, Stéphane; Corre, Erwan; Guan, Yue; Vinu, Manikandan; La Cono, Violetta; Yakimov, Mickail; Stingl, Ulrich; Toffin, Laurent; Jebbar, Mohamed. |
| The complete genome sequence of Methanohalophilus halophilus DSM 3094T, a member of the Methanosarcinaceae family and the Methanosarcianales order, consists of 2,022,959 bp in one contig and contains 2,137 predicted genes. The genome is consistent with a halophilic methylotrophic anaerobic lifestyle, including the methylotrophic and CO2-H2 methanogensis pathways. |
| Tipo: Text |
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| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00372/48351/48523.pdf |
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| Phung, Duy Khanh; Etienne, Clarisse; Batista, Manon; Langendijk-genevaux, Petra; Moalic, Yann; Laurent, Sebastien; Liuu, Sophie; Morales, Violette; Jebbar, Mohamed; Fichant, Gwennaele; Bouvier, Marie; Flament, Didier; Clouet-d’orval, Béatrice. |
| A network of RNA helicases, endoribonucleases and exoribonucleases regulates the quantity and quality of cellular RNAs. To date, mechanistic studies focussed on bacterial and eukaryal systems due to the challenge of identifying the main drivers of RNA decay and processing in Archaea. Here, our data support that aRNase J, a 5′-3′ exoribonuclease of the β-CASP family conserved in Euryarchaeota, engages specifically with a Ski2-like helicase and the RNA exosome to potentially exert control over RNA surveillance, at the vicinity of the ribosome. Proteomic landscapes and direct protein–protein interaction analyses, strengthened by comprehensive phylogenomic studies demonstrated that aRNase J interplay with ASH-Ski2 and a cap exosome subunit. Finally,... |
| Tipo: Text |
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| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00610/72250/71056.pdf |
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| Registros recuperados: 41 | |
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