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Jean Guezennec - One of the best experts on this subject based on the ideXlab platform.
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halomonas profundus sp nov a new pha producing bacterium isolated from a deep sea Hydrothermal Vent shrimp
Journal of Applied Microbiology, 2008Co-Authors: Christelle Simoncolin, G H C Raguenes, Joelle Cozien, Jean GuezennecAbstract:Aims: The objective of the present work was to describe a new deep-sea, aerobic, mesophilic and heterotrophic bacterium, referenced as strain AT1214, able to produce polyhydroxyalkanoates (PHAs) under laboratory conditions. This bacterium was isolated from a shrimp collected nearby a Hydrothermal Vent located on the Mid-Atlantic Ridge. Methods and Results: This micro-organism, on the basis of the phenotypical features and genotypic investigations, can be clearly assigned to the Halomonas genus and the name of Halomonas profundus is proposed. Optimal growth occurred between 32 and 37°C at a pH between 8 and 9 and at ionic strength between 20 and 30 g l−1 of sea salts. The G + C content of DNA was 58·6%. This bacterium produced PHAs of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from different carbon sources. Conclusions: The bacterium H. profundus produces PHA of 3HB and 3HV monomers from different carbon sources. Significance and Impact of the Study: PHAs share physical and material properties that suggest them for application in various areas, and are considered as an alternative to nonbiodegradable plastics produced from fossil oils. In this study, we describe a new bacteria isolated from a deep-sea Hydrothermal Vent with the capability to produce polyesters of biotechnological interest.
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a novel highly viscous polysaccharide excreted by an alteromonas isolated from a deep sea Hydrothermal Vent shrimp
Current Microbiology, 2003Co-Authors: G H C Raguenes, Marieanne Cambonbonavita, Jean Francois Lohier, Claire Boisset, Jean GuezennecAbstract:A deep-sea, mesophilic, aerobic, and heterotrophic microorganism, able to produce an extracellular polysaccharide, was isolated from a shrimp collected near an active Hydrothermal Vent of the Mid-Atlantic Ridge. On the basis of phenotypic and phylogenetic analyses and DNA/DNA relatedness, this strain could be assigned to the species Alteromonas macleodii as a variant of the fijiensis subspecies. It was selected for its ability to exhibit a swarming mucoid phenotype on specific media. The bacterium secreted, under laboratory conditions, an extremely viscous exopolysaccharide consisting of glucose, galactose as neutral sugars, and glucuronic, galacturonic acids as uronic acids, along with pyruvate and acetate as main substituents.
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structural studies of an exopolysaccharide produced by alteromonas macleodii subsp fijiensis originating from a deep sea Hydrothermal Vent
Carbohydrate Research, 1998Co-Authors: Helene Rougeaux, Russell W Carlson, Philippe Talaga, Jean GuezennecAbstract:Abstract The structure of the exopolysaccharide produced by Alteromonas macleodii subsp. fijiensis recovered from a deep-sea Hydrothermal Vent has been investigated. By means of chemical analysis and NMR studies, the repeating unit of the polymer was deduced to be a branched hexasaccharide with the structure shown. Download : Download full-size image
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alteromonas infernus sp nov a new polysaccharide producing bacterium isolated from a deep sea Hydrothermal Vent
Journal of Applied Microbiology, 1997Co-Authors: G H C Raguenes, Mikael Loaec, A Peres, Helene Rougeaux, Richard Christen, Raymond Ruimy, Patricia Pignet, Jean GuezennecAbstract:G. BARBIER AND J.G. GUEZENNEC. 1997.A deep-sea, aerobic, mesophilic and heterotrophic new bacterium was isolated from a sample of fluid collected among a dense population of Riftia pachyptila, in the vicinity of an active Hydrothermal Vent of the Southern depression of the Guaymas basin (Gulf of California). On the basis of phenotypic and phylogenetic analyses and DNA/DNA relatedness, the strain GY785 was recognized as a new species of the genus Alteromonas and the name of Alteromonas infernus is proposed. During the stationary phase in batch cultures in the presence of glucose, this bacterium secreted two unusual polysaccharides. The water-soluble exopolysaccharide-1 produced contained glucose, galactose, galacturonic and glucuronic acids as monosaccharides. The gel-forming exopolysaccharide-2 was separated from the bacterial cells by dialysis against distilled water and partially characterized.
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description of a new polymer secreting bacterium from a deep sea Hydrothermal Vent alteromonas macleodii subsp fijiensis and preliminary characterization of the polymer
Applied and Environmental Microbiology, 1996Co-Authors: G H C Raguenes, A Peres, Helene Rougeaux, Richard Christen, Patricia Pignet, G Gauthier, Georges Barbier, Jean GuezennecAbstract:A deep-sea, aerobic, mesophilic, heterotrophic bacterium was isolated from fluid collected near an active Hydrothermal Vent. On the basis of phenotypic and phylogenetic analyses and DNA-DNA relatedness, strain ST716 could be assigned to the species Alteromonas macleodii as a new subspecies. This bacterium secreted an unusual high-molecular-weight polysaccharide in the presence of glucose in batch cultures. The viscosity of this exopolysaccharide is of the same order of magnitude as that of xanthan, another bacterial polysaccharide of industrial interest. This polysaccharide, produced during the stationary phase, contained glucose, mannose, pyruvated mannose, and galactose along with galacturonic acid and glucuronic acid.
Zhongli Sha - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic position of alvinocarididae crustacea decapoda caridea new insights into the origin and evolutionary history of the Hydrothermal Vent alvinocarid shrimps
Deep Sea Research Part I: Oceanographic Research Papers, 2018Co-Authors: Shaoe Sun, Zhongli Sha, Yanrong WangAbstract:Abstract The deep-sea Hydrothermal Vent is one of typical extreme environments on Earth that assembles with the early life circumstance. The alvinocarid shrimps comprise the predominant faunal biomass of various Hydrothermal ecosystems, representing the key elements of Hydrothermal communities of Vent fields. Few molecular studies have examined the phylogenetic position, origin and evolutionary history of alvinocarid shrimps because of the limited availability of this taxon for genetic analyses. On the basis of three mitochondrial genes, three nuclear genes, and 12 selected alvinocarid species, our study is the first to secure the placement of alvinocarids within the infraorder Caridea. The results revealed that alvinocarid shrimps may have the closest deep-sea relatives, which originated earlier from shallow water. This result is consistent with the extinction/repopulation hypothesis. The divergence time estimates indicate that Hydrothermal Vent alvinocarid shrimps colonized the Vent ecosystems in Early Oligocene (34.60 Mya). The widespread extinctions of deep-sea faunas during the Late Cretaceous/Early Tertiary created opportunities for invasion of these habitats by the modern taxa. Our analyses suggest that the Western Pacific Ocean with complex back-arc basins was more likely to serve as a pivotal role as a centre of dispersal for the alvinocarid shrimps. Then they invaded into the Atlantic by circumglobal colonization westwards through the Indian Ocean, and invaded into the East-Pacific Ridge, respectively. Our conclusion suggest that the geological processes and dispersal mechanisms discussed here will play an important role revealing the origin and the evolution of the chemosynthetic-fauna in deep-sea Hydrothermal Vents.
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the complete mitochondrial genome of the alvinocaridid shrimp shinkaicaris leurokolos decapoda caridea insight into the mitochondrial genetic basis of deep sea Hydrothermal Vent adaptation in the shrimp
Comparative Biochemistry and Physiology Part D: Genomics and Proteomics, 2018Co-Authors: Shaoe Sun, Ming Hui, Minxiao Wang, Zhongli ShaAbstract:Abstract Deep-sea Hydrothermal Vent is one of the most extreme environments on Earth with low oxygen and high levels of toxins. Decapod species from the family Alvinocarididae have colonized and successfully adapted to this extremely harsh environment. Mitochondria plays a vital role in oxygen usage and energy metabolism, thus it may be under selection in the adaptive evolution of the Hydrothermal Vent shrimps. In this study, the mitochondrial genome (mitogenome) of alvinocaridid shrimp Shinkaicaris leurokolos (Kikuchi & Hashimoto, 2000) was determined through Illumina sequencing. The mitogenome of S. leurokolos was 15,903 bp in length, containing 13 protein-coding genes, 2 rRNAs, and 22 tRNAs. The gene order and orientation were identical to those of sequenced alvinocaridids. It has the longest concatenated sequences of protein-coding genes, tRNAs and shortest pooled rRNAs among the alvinocaridids. The control regions (CRs) of alvinocaridid were significantly longer ( p atp6 , cox1 , cox3 , cytb and nad1–5 . This study explores the mitochondrial genetic basis of Hydrothermal Vent adaptation in alvinocaridid for the first time, and provides valuable clues regarding the adaptation.
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probathylepadidae a new family of scalpelliformes thoracica cirripedia crustacea for probathylepas faxian gen nov sp nov from a Hydrothermal Vent in the okinawa trough
Zootaxa, 2015Co-Authors: Xianqiu Ren, Zhongli ShaAbstract:A new pedunculate barnacle, Probathylepas faxian gen. and sp. nov., is described from a Hydrothermal Vent in the Okinawa Trough. A new scalpelliform family, Probathylepadidae, is also proposed for the new genus and species. Probathylepadidae differs from all other five families of the order Scalpelliformes by the capitulum bearing eight primal plates and two whorls of imbricating supplementary plates, and the peduncle being without scales. The relationships between the species of the new family and sessile barnacles are also discussed.
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a new species of the genus neoverruca cirripedia thoracica verrucidea neoverrucidae from a Hydrothermal Vent area in the okinawa trough
Crustaceana, 2015Co-Authors: Zhongli Sha, Xianqiu RenAbstract:A new species of the neoverrucid barnacle genus Neoverruca Newman, 1989, N. intermedia sp. nov., collected from a Hydrothermal Vent area in the Okinawa Trough, is described and illustrated. It differs from N. brachylepadoformis Newman, 1989 by the apical end of the inner surface of the movable scutum being in a pocket-form, with a longitudinal groove upwards, and without median ridges; the adductor ridge (or myophore) of the fixed scutum stout and the inner distal part of the scutum without longitudinal ridge.
Helene Rougeaux - One of the best experts on this subject based on the ideXlab platform.
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structural studies of an exopolysaccharide produced by alteromonas macleodii subsp fijiensis originating from a deep sea Hydrothermal Vent
Carbohydrate Research, 1998Co-Authors: Helene Rougeaux, Russell W Carlson, Philippe Talaga, Jean GuezennecAbstract:Abstract The structure of the exopolysaccharide produced by Alteromonas macleodii subsp. fijiensis recovered from a deep-sea Hydrothermal Vent has been investigated. By means of chemical analysis and NMR studies, the repeating unit of the polymer was deduced to be a branched hexasaccharide with the structure shown. Download : Download full-size image
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alteromonas infernus sp nov a new polysaccharide producing bacterium isolated from a deep sea Hydrothermal Vent
Journal of Applied Microbiology, 1997Co-Authors: G H C Raguenes, Mikael Loaec, A Peres, Helene Rougeaux, Richard Christen, Raymond Ruimy, Patricia Pignet, Jean GuezennecAbstract:G. BARBIER AND J.G. GUEZENNEC. 1997.A deep-sea, aerobic, mesophilic and heterotrophic new bacterium was isolated from a sample of fluid collected among a dense population of Riftia pachyptila, in the vicinity of an active Hydrothermal Vent of the Southern depression of the Guaymas basin (Gulf of California). On the basis of phenotypic and phylogenetic analyses and DNA/DNA relatedness, the strain GY785 was recognized as a new species of the genus Alteromonas and the name of Alteromonas infernus is proposed. During the stationary phase in batch cultures in the presence of glucose, this bacterium secreted two unusual polysaccharides. The water-soluble exopolysaccharide-1 produced contained glucose, galactose, galacturonic and glucuronic acids as monosaccharides. The gel-forming exopolysaccharide-2 was separated from the bacterial cells by dialysis against distilled water and partially characterized.
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description of a new polymer secreting bacterium from a deep sea Hydrothermal Vent alteromonas macleodii subsp fijiensis and preliminary characterization of the polymer
Applied and Environmental Microbiology, 1996Co-Authors: G H C Raguenes, A Peres, Helene Rougeaux, Richard Christen, Patricia Pignet, G Gauthier, Georges Barbier, Jean GuezennecAbstract:A deep-sea, aerobic, mesophilic, heterotrophic bacterium was isolated from fluid collected near an active Hydrothermal Vent. On the basis of phenotypic and phylogenetic analyses and DNA-DNA relatedness, strain ST716 could be assigned to the species Alteromonas macleodii as a new subspecies. This bacterium secreted an unusual high-molecular-weight polysaccharide in the presence of glucose in batch cultures. The viscosity of this exopolysaccharide is of the same order of magnitude as that of xanthan, another bacterial polysaccharide of industrial interest. This polysaccharide, produced during the stationary phase, contained glucose, mannose, pyruvated mannose, and galactose along with galacturonic acid and glucuronic acid.
G H C Raguenes - One of the best experts on this subject based on the ideXlab platform.
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halomonas profundus sp nov a new pha producing bacterium isolated from a deep sea Hydrothermal Vent shrimp
Journal of Applied Microbiology, 2008Co-Authors: Christelle Simoncolin, G H C Raguenes, Joelle Cozien, Jean GuezennecAbstract:Aims: The objective of the present work was to describe a new deep-sea, aerobic, mesophilic and heterotrophic bacterium, referenced as strain AT1214, able to produce polyhydroxyalkanoates (PHAs) under laboratory conditions. This bacterium was isolated from a shrimp collected nearby a Hydrothermal Vent located on the Mid-Atlantic Ridge. Methods and Results: This micro-organism, on the basis of the phenotypical features and genotypic investigations, can be clearly assigned to the Halomonas genus and the name of Halomonas profundus is proposed. Optimal growth occurred between 32 and 37°C at a pH between 8 and 9 and at ionic strength between 20 and 30 g l−1 of sea salts. The G + C content of DNA was 58·6%. This bacterium produced PHAs of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from different carbon sources. Conclusions: The bacterium H. profundus produces PHA of 3HB and 3HV monomers from different carbon sources. Significance and Impact of the Study: PHAs share physical and material properties that suggest them for application in various areas, and are considered as an alternative to nonbiodegradable plastics produced from fossil oils. In this study, we describe a new bacteria isolated from a deep-sea Hydrothermal Vent with the capability to produce polyesters of biotechnological interest.
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a novel highly viscous polysaccharide excreted by an alteromonas isolated from a deep sea Hydrothermal Vent shrimp
Current Microbiology, 2003Co-Authors: G H C Raguenes, Marieanne Cambonbonavita, Jean Francois Lohier, Claire Boisset, Jean GuezennecAbstract:A deep-sea, mesophilic, aerobic, and heterotrophic microorganism, able to produce an extracellular polysaccharide, was isolated from a shrimp collected near an active Hydrothermal Vent of the Mid-Atlantic Ridge. On the basis of phenotypic and phylogenetic analyses and DNA/DNA relatedness, this strain could be assigned to the species Alteromonas macleodii as a variant of the fijiensis subspecies. It was selected for its ability to exhibit a swarming mucoid phenotype on specific media. The bacterium secreted, under laboratory conditions, an extremely viscous exopolysaccharide consisting of glucose, galactose as neutral sugars, and glucuronic, galacturonic acids as uronic acids, along with pyruvate and acetate as main substituents.
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alteromonas infernus sp nov a new polysaccharide producing bacterium isolated from a deep sea Hydrothermal Vent
Journal of Applied Microbiology, 1997Co-Authors: G H C Raguenes, Mikael Loaec, A Peres, Helene Rougeaux, Richard Christen, Raymond Ruimy, Patricia Pignet, Jean GuezennecAbstract:G. BARBIER AND J.G. GUEZENNEC. 1997.A deep-sea, aerobic, mesophilic and heterotrophic new bacterium was isolated from a sample of fluid collected among a dense population of Riftia pachyptila, in the vicinity of an active Hydrothermal Vent of the Southern depression of the Guaymas basin (Gulf of California). On the basis of phenotypic and phylogenetic analyses and DNA/DNA relatedness, the strain GY785 was recognized as a new species of the genus Alteromonas and the name of Alteromonas infernus is proposed. During the stationary phase in batch cultures in the presence of glucose, this bacterium secreted two unusual polysaccharides. The water-soluble exopolysaccharide-1 produced contained glucose, galactose, galacturonic and glucuronic acids as monosaccharides. The gel-forming exopolysaccharide-2 was separated from the bacterial cells by dialysis against distilled water and partially characterized.
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description of a new polymer secreting bacterium from a deep sea Hydrothermal Vent alteromonas macleodii subsp fijiensis and preliminary characterization of the polymer
Applied and Environmental Microbiology, 1996Co-Authors: G H C Raguenes, A Peres, Helene Rougeaux, Richard Christen, Patricia Pignet, G Gauthier, Georges Barbier, Jean GuezennecAbstract:A deep-sea, aerobic, mesophilic, heterotrophic bacterium was isolated from fluid collected near an active Hydrothermal Vent. On the basis of phenotypic and phylogenetic analyses and DNA-DNA relatedness, strain ST716 could be assigned to the species Alteromonas macleodii as a new subspecies. This bacterium secreted an unusual high-molecular-weight polysaccharide in the presence of glucose in batch cultures. The viscosity of this exopolysaccharide is of the same order of magnitude as that of xanthan, another bacterial polysaccharide of industrial interest. This polysaccharide, produced during the stationary phase, contained glucose, mannose, pyruvated mannose, and galactose along with galacturonic acid and glucuronic acid.
Colleen M Cavanaugh - One of the best experts on this subject based on the ideXlab platform.
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cloning and sequencing of a form ii ribulose 1 5 bisphosphate carboxylase oxygenase from the bacterial symbiont of the Hydrothermal Vent tubeworm riftia pachyptila
Journal of Bacteriology, 1998Co-Authors: Jonathan J Robinson, Jeffrey L Stein, Colleen M CavanaughAbstract:The bacterial symbiont of the Hydrothermal Vent tubeworm fixes carbon via the Calvin-Benson cycle and has been shown previously to express a form II ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO). The gene cbbM, which encodes this enzyme, has been cloned and sequenced. The gene has the highest identity with the cbbM gene from Rhodospirillum rubrum, and analysis of the inferred amino acid sequence reveals that all active-site residues are conserved. This is the first form II RubisCO cloned and sequenced from a chemoautotrophic symbiont and from a deep-sea organism.
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dominance of one bacterial phylotype at a mid atlantic ridge Hydrothermal Vent site
Proceedings of the National Academy of Sciences of the United States of America, 1995Co-Authors: Martin F Polz, Colleen M CavanaughAbstract:Abstract Microbial community structure in natural environments has remained largely unexplored yet is generally considered to be complex. It is shown here that in a Mid-Atlantic Ridge Hydrothermal Vent habitat, where food webs depend on prokaryotic primary production, the surface microbial community consists largely of only one bacterial phylogenetic type (phylotype) as indicated by the dominance of a single 16S rRNA sequence. The main part of its population occurs as an ectosymbiont on the dominant animals, the shrimp Rimicaris exoculata, where it grows as a monoculture within the carapace and on the extremities. However, the same bacteria are also the major microbial component of the free-living substrate community. Phylogenetically, this type forms a distinct branch within the epsilon-Proteobacteria. This is different from all previously studied chemoautotrophic endo- and ectosymbioses from Hydrothermal Vents and other sulfidic habitats in which all the bacterial members cluster within the gamma-Proteobacteria.
