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Registros recuperados: 13 | |
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Gaill, F; Herbage, D; Lepescheux, L. |
The structure of the cuticle from the "Pompeii worm" Alvinella pompejana and Riftia pachyptila is presented. The cuticle structure of Alvinella is similar to that of other annelid species, whereas that of Riftia presents patterns which are observed in biological analogues of cholesteric liquid crystals. The amino acid composition of a vestimentiferan cuticle is presented for the first time and compared with that of other invertebrates. |
Tipo: Text |
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Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00267/37812/35893.pdf |
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Zbinden, M; Shillito, B; Le Bris, Nadine; De Montlaur, C; Roussel, Erwan; Guyot, F; Gaill, F; Cambon-bonavita, Marie-anne. |
The Rimicaris exoculata dominates the megafauna of some of the Mid Atlantic ridge hydrothermal vent sites. This species harbors a rich community of bacterial epibionts inside its gill chamber. Literature data indicate that a single 16S rRNA phylotype dominates this epibiotic community, and is assumed to be a sulfide-oxidizing bacteria. However attempts Of Cultivation were not successful and did not allow to confirm it. The aim of our study was to test the hypothesis of sulfide oxidation in the gill chamber, by a multidisciplinary approach, using in vivo experiments at in situ pressure in the presence of sulfide, microscopic observations and a molecular survey. Morphology of microorganisms, before and after treatment, was analyzed to test the effect of... |
Tipo: Text |
Palavras-chave: Sulfur; Methane; Iron; Intracellular granules; Hydrothermal vent shrimp; High pressure experiments. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4563.pdf |
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Cosson-mannevy, M-a; Cosson, R P; Gaill, F; Laubier, L. |
Specimens of Riftia pachyptila and Alvinella pompejana were collected during the Biocyarise expedition to hydrothermal vents on the East Pacific Rise at 13 degree N. Quantitative data describing the concentrations of metals in Riftia pachyptila showed that numerous metals are highly concentrated. Analyses of tissues reveal that the plume and the trophosome are the main sites of metal accumulation. Bioconcentration links with the mineral composition of the vent environment are discussed. Mechanisms for metal detoxication were investigated in both species: the presence of metal-rich granules and metallothionein-like proteins were observed. The role of chemolithotrophic bacteria in these mechanisms is discussed. |
Tipo: Text |
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Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00267/37830/35911.pdf |
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Gulik, A; Gaill, F. |
A freeze fracture morphological study of Alvinella pompejana associated epibiotic bacteria has confirmed the large variety of bacterial species already observed by scanning and thin section transmission electron microscopy. Freeze-fracture reveals striking differences in the membrane structure: The usual fracture along the hydrophobic part of the membrane for some bacteria, but only an unusual cross-fracture through the membrane for others. This suggests that some bacteria contain non-fracturable lipids typical of certain archaebacteria. |
Tipo: Text |
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Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00267/37788/35869.pdf |
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Pradillon, F; Le Bris, Nadine; Shillito, B; Young, C; Gaill, F. |
Dispersal and colonisation processes at deep-sea vents are still not fully understood, essentially because early life stages of vent species remain unknown. The polychaete worm Alvinella pompejana forms colonies on chimney walls at East Pacific Rise vent sites where the temperature can frequently exceed 20 degrees C. In vitro studies in pressure vessels showed that the early embryos tolerate temperatures in a lower range (10-14 degrees C), suggesting that they would have to escape the colony to develop. Pressure vessels offer the advantage that each parameter can be independently controlled, but they do not simulate the more complex and dynamic conditions naturally encountered at vent sites. Accordingly, in addition to incubations in pressure vessels, we... |
Tipo: Text |
Palavras-chave: Environmental condition; H2S; Temperature tolerance; Polychaete; Pressure vessel; Embryo; Development; Hydrothermal vent. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-600.pdf |
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Shillito, B; Le Bris, Nadine; Hourdez, S; Ravaux, J; Cottin, D; Caprais, Jean-claude; Jollivet, D; Gaill, F. |
The shrimp Mirocaris fortunata is a hydrothermal vent species that is found at most vent-sites along the Mid-Atlantic Ridge. This endemic species is found across a hydrothermal gradient, with thermal conditions ranging from 2-9 degrees C in ambient seawater to fairly warm values of about 25 degrees C. We performed in vivo experiments on M. fortunata specimens originating from different sites and depths (850 m to 2300 m), both at atmospheric pressure and in pressurized aquaria, to characterise the upper thermal limits of this species. Atmospheric pressure results show that thermal physiology should be studied at each population's native pressure. At in situ pressure, shrimps from Menez Gwen (850 m depth) and Lucky Strike (1700 m depth) do not survive... |
Tipo: Text |
Palavras-chave: IPOCAMP TM; Crustacea; Mirocaris fortunata; Thermal stress; Hydrothermal vent. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1240.pdf |
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Duperron, Sebastien; Halary, S; Lorion, J; Sibuet, Myriam; Gaill, F. |
Bathymodioline mussels occur in chemosynthesis-based ecosystems such as cold seeps, hydrothermal vents and organic debris worldwide. Their key adaptation to these environments is their association with bacterial endosymbionts which ensure a chemosynthetic primary production based on the oxidation of reduced compounds such as methane and sulfide. We herein report a multiple symbiosis involving six distinct bacterial 16S rRNA phylotypes, including two belonging to groups not yet reported as symbionts in mytilids, in a small Idas mussel found on carbonate crusts in a cold seep area located north to the Nile deep-sea fan (Eastern Mediterranean). Symbionts co-occur within hosts bacteriocytes based on fluorescence in situ hybridizations, and sequencing of... |
Tipo: Text |
Palavras-chave: Eastern Mediterranean; Cold seeps; Bathymodiolus; Idas; Mytilidae; Symbiosis. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3928.pdf |
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Zbinden, M; Le Bris, Nadine; Gaill, F; Compere, P. |
The shrimp Rimicaris exoculata dominates the megafauna of some Mid-Atlantic Ridge hydrothermal vent fields. This species harbours a rich bacterial epibiosis inside its gill chamber. At the 'Rainbow' vent site (36degrees 14.0'N), the epibionts are associated with iron oxide deposits. Investigation of both bacteria and minerals by scanning electron microscopy (SEM) and X-ray microanalysis (EDX) revealed 3 distinct compartments in the gill chamber: (1) the lower pre-branchial chamber, housing bacteria but devoid of minerals; (2) the 'true' branchial chamber, containing the gills and devoid of both bacteria and minerals; and (3) the upper pre-branchial chamber, housing the main ectosymbiotic bacterial community and associated mineral deposits. Our chemical and... |
Tipo: Text |
Palavras-chave: Crustacea; Deep sea; Moulting cycle; Biomineralisation; Symbiosis; Iron oxidation. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/00000/10919/7584.pdf |
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Gaill, F; Desbruyeres, Daniel; Prieur, D. |
A morphological study of bacteria associated with the “Pompei worm,”Alvinella pompejana, collected from East Pacific rise hydrothermal vents, revealed four types of epidermal associations on the dorsal part of the animals: various single cells distributed on the animal tegument; clump-like associations located in the intertegumentary spaces; and filamentous bacteria associated with epidermal expansions, or inserted on the posterior parapodia. The bacterial morphologies were illustrated by SEM and TEM pictures and compared to bacteria previously described. The functional significance of these associations is discussed. |
Tipo: Text |
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Ano: 1987 |
URL: http://archimer.ifremer.fr/doc/00155/26658/24855.pdf |
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Cottin, D; Ravaux, J; Leger, N; Halary, S; Toullec, J; Sarradin, Pierre-marie; Gaill, F; Shillito, B. |
The annelid Paralvinella grasslei is a deep-sea vent endemic species that colonizes the wall of active chimneys. We report here the first data on its thermal biology based on in vivo experiments in pressurized aquaria. Our results demonstrate that P. grasslei survives a 30 min exposure at 30 degrees C, and suggest that the upper thermal limit of this species is slightly above this temperature. The first signs of stress were noticed at 30 C, such as a significant increase in the animal's activity and the expression of HSP70 stress proteins. A preliminary investigation of the kinetics of stress protein expression surprisingly showed high levels of HSP70 proteins as late as 3.5 h after the heat shock. Finally, we provide here the first sequences for vent... |
Tipo: Text |
Palavras-chave: IPOCAMP; Annelids; Heat stress; Stress response; Heat shock proteins; Hydrothermal vents. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4570.pdf |
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Registros recuperados: 13 | |
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