Fiche participant :
Nom : Gros
Prénom : Olivier
Liste des participations aux campagnes accessibles [+] [-]
- KARUBENTHOS 2
- Leg 1 (Sun Jun 07 00:00:00 CEST 2015 - Tue Jun 16 00:00:00 CEST 2015)
- Tri, conditionnement ( Université des Antilles et de la Guyane)
- KARUBENTHOS 2012
- Première partie (Wed May 02 00:00:00 CEST 2012 - Mon May 28 00:00:00 CEST 2012)
- Collecte - Plongée (Polyvalence, Université des Antilles et de la Guyane)
- PANGLAO 2005
- (Sun May 22 00:00:00 CEST 2005 - Wed Jun 01 00:00:00 CEST 2005)
- Collecte - Tri (Biologie marine, Université des Antilles et de la Guyane)
Bibliographie (6) [+] [-]
Exporter les bibliographies
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Duperron S., Laurent M.C., Gaill F. & Gros O. 2008. Sulphur-oxidizing extracellular bacteria in the gills of Mytilidae associated with wood falls: Thiotrophic epibionts in sunken wood mussels. FEMS Microbiology Ecology 63(3): 338-349. DOI:10.1111/j.1574-6941.2008.00438.x
Résumé [+] [-]Six morphotypes of small mussels (Bivalvia: Mytilidae) were found attached to naturally sunken wood collected in the Bohol Sea (Philippines). These specimens are related to the large Bathymodiolus mussels that are found worldwide at cold seeps and hydrothermal vents. In these habitats, the mytilids harbour sulphur- and methane-oxidizing endosymbionts in their gills and depend on the energy and carbon provided by the symbionts. In this study, bacteria associated with the gills of wood-associated mussels are characterized using molecular and microscopic techniques. The existence of bacteria in the lateral zone of gill filaments in all specimens is demonstrated. Comparative analyses of 16S rRNA gene and adenosine 5'-phosphosulphate (APS) reductase gene sequences indicate that the bacteria are closely related to sulphur-oxidizing endosymbionts of Bathymodiolus. FISHs using specific probes confirm that sulphur oxidizers are by far the most abundant, if not the only bacteria present. Electron micrographs displayed mostly extracellular bacteria located between microvilli at the apical surface of host gill epithelial cells all along the lateral zone of each gill filament. In some specimens, occasional occurrence of intracellular bacteria with similar morphology was noted. This study provides the first molecular evidence for the presence of possible thiotrophic symbiosis in sunken wood ecosystems. With their epibiotic bacteria, wood-associated mussels display a less integrated type of interaction than described in their seep, vent and whale fall relatives.
Campagnes accessibles citées (1) [+] [-]
Codes des collections associés: IM (Mollusques) -
Duperron S., Lorion J., Samadi S., Gros O. & Gaill F. 2009. Symbioses between deep-sea mussels (Mytilidae: Bathymodiolinae) and chemosynthetic bacteria: diversity, function and evolution. Comptes Rendus Biologies 332(2-3): 298-310. DOI:10.1016/j.crvi.2008.08.003
Résumé [+] [-]Mussels of the subfamily Bathymodiolinae thrive around chimneys emitting hot fluids at deep sea hydrothermal vents, as well as at cold seeps and on sunken organic debris (sunken wood, whale falls). Despite the absence of light-driven primary production in these deep-sea ecosystems, mussels succeed reaching high biomasses in these harsh conditions thanks to chemosynthetic, carbon-fixing bacterial symbionts, located in their gill tissue. Since the discovery of mussel symbioses about three decades ago our knowledge has increased, yet new findings are published regularly regarding their diversity, role and evolution. This article attempts to summarize current knowledge about symbiosis in Bathymodiolinae, focusing on mussel species for which information is available regarding both hosts and symbionts. Moreover, new data obtained from small mussels inhabiting sunken woods around the Philippines are provided. Indeed, mussel species from organic falls remain poorly studied compared to their vent and seep relatives despite their importance for the understanding of the evolution of symbiosis in the subfamily Bathymodiolinae. To cite this article: S. Duperron et al., C. R. Biologies 332 (2009). (C) 2008 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.
Campagnes accessibles citées (2) [+] [-]
Codes des collections associés: IM (Mollusques) -
Gros O., Guibert J. & Gaill F. 2007. Gill-symbiosis in mytilidae associated with wood fall environments. Zoomorphology 126(3): 163-172. DOI:10.1007/s00435-007-0035-3
Résumé [+] [-]Bivalves belonging to the genera Idas and Adipicola were collected from wood fall environments in the west Pacific (Vanuatu islands) between 300 and 890 m depths in 2004. Bacterial symbionts were checked by three complementary techniques: histological and DAPI staining, in situ hybridization (FISH), and TEM. No bacteria were detected inside the gills of the two species, rejecting the endosymbiosis hypothesis. However, results from our study demonstrated the existence of ectosymbionts colonizing microvilli differentiated at the apical surface of the cells constituting the lateral zone of gill filaments. These ectosymbionts are gamma-Proteobacteria due to their strong hybridization with the specific probe GAM42; in contrast no hybridization was obtained from either gills or other host tissues by using the oligonucleotide probes specific to alpha- beta- and delta-Proteobacteria. Based on TEM observations, these Gram-negative bacterial symbionts are not methanotrophic due to the lack of concentric stacking of intracellular membranes in their cytoplasm. Such ectosymbionts may represent thioautotrophic bacteria as already described in various Mytilidae from hydrothermal vents and cold seeps. Unfortunately, no phylogenetic analysis could be done in this study to compare their DNA sequence to that of other marine invertebrate symbionts described to date.
Campagnes accessibles citées (1) [+] [-]
Codes des collections associés: IM (Mollusques) -
Lorion J., Duperron S., Gros O., Cruaud C. & Samadi S. 2009. Several deep-sea mussels and their associated symbionts are able to live both on wood and on whale falls. Proceedings of the Royal Society B: Biological Sciences 276(1654): 177-185. DOI:10.1098/rspb.2008.1101
Résumé [+] [-]Bathymodiolin mussels occur at hydrothermal vents and cold seeps, where they thrive thanks to symbiotic associations with chemotrophic bacteria. Closely related genera Idas and Adipicola are associated with organic falls, ecosystems that have been suggested as potential evolutionary 'stepping stones' in the colonization of deeper and more sulphide-rich environments. Such a scenario should result from specializations to given environments from species with larger ecological niches. This study provides molecular-based evidence for the existence of two mussel species found both on sunken wood and bones. Each species specifically harbours one bacterial phylotype corresponding to thioautotrophic bacteria related to other bathymodiolin symbionts. Phylogenetic patterns between hosts and symbionts are partially congruent. However, active endocytosis and occurrences of minor symbiont lineages within species which are not their usual host suggest an environmental or horizontal rather than strictly vertical transmission of symbionts. Although the bacteria are close relatives, their localization is intracellular in one mussel species and extracellular in the other, suggesting that habitat choice is independent of the symbiont localization. The variation of bacterial densities in host tissues is related to the substrate on which specimens were sampled and could explain the abilities of host species to adapt to various substrates.
Campagnes accessibles citées (3) [+] [-]
Codes des collections associés: IM (Mollusques), IU (Crustacés) -
Thubaut J., Corbari L., Gros O., Duperron S., Couloux A. & Samadi S. 2013. Integrative Biology of Idas iwaotakii (Habe, 1958), a ‘Model Species’ Associated with Sunken Organic Substrates. PLoS ONE 8(7): e69680. DOI:10.1371/journal.pone.0069680
Résumé [+] [-]The giant bathymodioline mussels from vents have been studied as models to understand the adaptation of organisms to deep-sea chemosynthetic environments. These mussels are closely related to minute mussels associated to organic remains decaying on the deep-sea floor. Whereas biological data accumulate for the giant mussels, the small mussels remain poorly studied. Despite this lack of data for species living on organic remains it has been hypothesized that during evolution, contrary to their relatives from vents or seeps, they did not acquire highly specialized biological features. We aim at testing this hypothesis by providing new biological data for species associated with organic falls. Within Bathymodiolinae a close phylogenetic relationship was revealed between the Bathymodiolus sensu stricto lineage (i.e. "thermophilus'' lineage) which includes exclusively vent and seep species, and a diversified lineage of small mussels, attributed to the genus Idas, that includes mostly species from organic falls. We selected Idas iwaotakii (Habe, 1958) from this latter lineage to analyse population structure and to document biological features. Mitochondrial and nuclear markers reveal a north-south genetic structure at an oceanic scale in the Western Pacific but no structure was revealed at a regional scale or as correlated with the kind of substrate or depth. The morphology of larval shells suggests substantial dispersal abilities. Nutritional features were assessed by examining bacterial diversity coupled by a microscopic analysis of the digestive tract. Molecular data demonstrated the presence of sulphur-oxidizing bacteria resembling those identified in other Bathymodiolinae. In contrast with most Bathymodiolus s.s. species the digestive tract of I. iwaotakii is not reduced. Combining data from literature with the present data shows that most of the important biological features are shared between Bathymodiolus s.s. species and its sister-lineage. However Bathymodiolus s.s. species are ecologically more restricted and also display a lower species richness than Idas species.
Campagnes accessibles citées (7) [+] [-]
Codes des collections associés: IU (Crustacés) -
Volland J.M., Frenkiel L., Aldana aranda D. & Gros O. 2010. Occurrence of Sporozoa-like microorganisms in the digestive gland of various species of Strombidae. Journal of Molluscan Studies 76(2): 196-198. DOI:10.1093/mollus/eyq005
Campagnes accessibles citées (1) [+] [-]
Codes des collections associés: IM (Mollusques)