- Microbial Community Ecology and Physiology
- Marine Biology and Ecology Research
- Genomics and Phylogenetic Studies
- Methane Hydrates and Related Phenomena
- Crustacean biology and ecology
- Coral and Marine Ecosystems Studies
- Insect symbiosis and bacterial influences
- Parasite Biology and Host Interactions
- Marine and fisheries research
- Marine Bivalve and Aquaculture Studies
- Environmental DNA in Biodiversity Studies
- Protist diversity and phylogeny
- Isotope Analysis in Ecology
- Geology and Paleoclimatology Research
- Hydrocarbon exploration and reservoir analysis
- Aquaculture Nutrition and Growth
- Enzyme Production and Characterization
- Microbial Fuel Cells and Bioremediation
- Cephalopods and Marine Biology
- Paleontology and Stratigraphy of Fossils
- Ichthyology and Marine Biology
- Ocean Acidification Effects and Responses
- Aquaculture disease management and microbiota
- Geochemistry and Geologic Mapping
- Insect Utilization and Effects
Université de Bretagne Occidentale
2016-2025
Ifremer
2016-2025
Centre National de la Recherche Scientifique
2015-2024
Biology of Extremophiles Laboratory
2008-2021
Institut Universitaire Européen de la Mer
2009-2018
Cardiff University
2008
Biologie Intégrative des Organismes Marins
2001
Observatoire Océanologique de Banyuls-sur-Mer
2001
Remote deep-ocean sediment (DOS) ecosystems are among the least explored biomes on Earth. Genomic assessments of their biodiversity have failed to separate indigenous benthic organisms from sinking plankton. Here, we compare global-scale eukaryotic DNA metabarcoding datasets (18S-V9) abyssal and lower bathyal surficial sediments euphotic aphotic ocean pelagic layers distinguish plankton diversity in material. Based 1685 samples collected throughout world ocean, show that DOS is at threefold...
Sub-sea-floor sediments may contain two-thirds of Earth's total prokaryotic biomass. However, this has its basis in data extrapolation from ~500-meter to 4-kilometer depths, whereas the deepest documented prokaryotes are only 842 meters. Here, we provide evidence for low concentrations living cells (1626 meters below sea floor), oldest (111 million years old), and potentially hottest (~100 degrees C) marine investigated. These Newfoundland margin also have DNA sequences related thermophilic...
Investigations of the diversity culturable yeasts at deep-sea hydrothermal sites have suggested possible interactions with endemic fauna. Samples were collected during various oceanographic cruises Mid-Atlantic Ridge, South Pacific Basins and East Rise. Cultures 32 isolates, mostly associated animals, collected. Phylogenetic analyses 26S rRNA gene sequences revealed that belonged to Ascomycota Basidiomycota phyla, identification several genera: Rhodotorula, Rhodosporidium, Candida,...
The shrimp Rimicaris exoculata from hydrothermal vents on the Mid-Atlantic Ridge (MAR) harbours bacterial epibionts specialized appendages and inner surfaces of its gill chamber. Using comparative 16S rRNA sequence analysis fluorescence in situ hybridization (FISH), we examined R. epibiosis four sites along known distribution range MAR. Our results show that lives symbiosis with two types filamentous epibionts. One belongs to Epsilonproteobacteria, was previously identified as dominant...
An obligate piezophilic anaerobic hyperthermophilic archaeon, designated strain CH1(T), was isolated from a hydrothermal vent site named 'Ashadze', which is located on the Mid-Atlantic Ridge at depth of 4100 m. Enrichment and isolation were carried out 95 °C under hydrostatic pressure 42 MPa. Cells CH1(T) highly motile irregular cocci with diameter ~1-1.5 µm. Growth recorded 80-108 (optimum 98 °C) pressures 20-120 MPa 52 MPa). No growth observed atmospheric 60-110 °C. pH 6.0-9.5 7.5-8.0) in...
ABSTRACT Next-generation sequencing (NGS) opens up exciting possibilities for improving our knowledge of environmental microbial diversity, allowing rapid and cost-effective identification both cultivated uncultivated microorganisms. However, library preparation, sequencing, analysis the results can provide inaccurate representations studied community compositions. Therefore, all these steps need to be taken into account carefully. Here we evaluated effects DNA extraction methods, targeted...
Abstract Despite representing one of the largest biomes on earth, biodiversity deep seafloor is still poorly known. Environmental DNA metabarcoding offers prospects for fast inventories and surveys, yet requires standardized sampling approaches careful choice environmental substrate. Here, we aimed to optimize genetic assessment prokaryote (16S), protistan (18S V4), metazoan V1–V2, COI) communities, by evaluating strategies sediment aboveground water, deployed simultaneously at deep-sea...
A thermophilic, anaerobic, chemo-organotrophic bacterium, designated MV1087T, was isolated from a deep-sea hydrothermal chimney sample collected the Mid-Atlantic Ridge. The cells were straight, motile and stained gram-negative. Growth observed 45 to 65 degrees C, with an optimum around C. No growth at 40 or 70 pH 5.5 9.0 7. salinity range for 10-100 g sea salt l(-1) (corresponding 6.5-65 NaCl l(-1)) 30 (20 l(-1)). Strain MV1087T heterotrophic, able ferment proteinaceous substrates, such as...
A novel thermophilic, anaerobic, hydrogen-oxidizing bacterium, designated strain AM1116T, was isolated from an East Pacific Rise hydrothermal vent sample. The cells were rod-shaped (1.01-5 x 0.5 microm), motile with polar flagella. They grew at temperatures between 50 and 70 degrees C (optimum 60 C; doubling time approximately 1.5 h), pH 5.0 7.5 around 5.5-6.0) in 10 40 g NaCl l(-1) 20-25 l(-1)). Cells chemolithoautotrophically a H2/CO2 atmosphere (80:20; 200 kPa). Poor heterotrophic growth...
Summary A pluri‐disciplinary in situ colonization experiment was performed to study early stages of deep‐sea vent Alvinella spp. worm habitats. Four devices were deployed onto colonies different chimneys the East‐Pacific Rise (EPR 13°N), for two periods: a short (less than week) and longer one (3 weeks). Video imagery monitoring thermal physico‐chemical conditions during experiments. Numerous microorganisms bearing specialized adhesion‐appendages and/or high amounts polymeric extracellular...
Rimicaris exoculata dominates the megafauna of several Mid-Atlantic Ridge hydrothermal sites. Its gut is full sulphides and iron-oxide particles harbours microbial communities. Although a trophic symbiosis has been suggested, their role remains unclear. In vivo starvation experiments in pressurized vessels were performed on shrimps from Rainbow Trans-Atlantic Geotraverse sites order to expel transient contents. Microbial communities associated with starved reference compared using 16S rRNA...
Aim Deep-sea hydrothermal vents are unstable habitats that both spatially and temporally fragmented. In vent species, a 'short-term insurance' hypothesis would lead us to expect mostly self-recruitment, limiting the loss of larvae in deep ocean or water column increasing genetic differentiation over time elapsed since colonization. Alternatively, 'long-term support prediction selection for large-scale dispersal, ensure long-term persistence these ephemeral habitats. The main goal this study...
The gill chamber of deep-sea hydrothermal vent shrimp Rimicaris exoculata hosts a dense community epibiotic bacteria dominated by filamentous Epsilonproteobacteria and Gammaproteobacteria. Using metagenomics on from the Rainbow field, we showed that both epibiont groups have potential to grow autotrophically oxidize reduced sulfur compounds or hydrogen with oxygen nitrate. For carbon fixation, use reductive tricarboxylic acid cycle, whereas Gammaproteobacteria Calvin-Benson-Bassham cycle....
Diversity and function in microbial mats from the Lucky Strike hydrothermal vent field (Mid-Atlantic Ridge) were investigated using molecular approaches. DNA RNA extracted mat samples overlaying deposits Bathymodiolus azoricus mussel assemblages. We constructed analyzed libraries of 16S rRNA gene sequences functional genes involved autotrophic carbon fixation [forms I II RuBisCO (cbbL/M), ATP-citrate lyase B (aclB)]; methane oxidation [particulate monooxygenase (pmoA)] sulfur...
As part of an ongoing examination microbial diversity associated with hydrothermal vent polychaetes the family Alvinellidae, we undertook a culture-independent molecular analysis bacterial assemblage mucous secretions Northeastern Pacific polychaete Paralvinella palmiformis. Using 16S rDNA-based phylogenetic approach, clone libraries were constructed from two samples collected active sulfide edifices in fields. In both cases, largely dominated by ε-Proteobacteria. Phylotypes belonging to...
A thermophilic, anaerobic, chemo-organotrophic sulfur-reducing bacterium, designated MV1075T, was isolated from a deep-sea hydrothermal chimney sample collected on the Mid-Atlantic Ridge. Cells were rod-shaped with sheath-like outer structure, motile polar flagella and stained Gram-negative. They appeared singly, in pairs or short chains. The temperature range for growth 25-65 degrees C, an optimum at 55 C. Growth observed pH 5 to 9, around 7. salinity 15-70 g sea salt l(-1) (corresponding...
Journal Article A novel polymer produced by a bacterium isolated from deep‐sea hydrothermal vent polychaete annelid Get access M.‐A. Cambon‐Bonavita, Cambon‐Bonavita Institut Français de Recherche pour l'Exploitation la Mer, Centre Brest, DRV/VP, Plouzané and Search for other works this author on: Oxford Academic Google Scholar G. Raguénès, Raguénès J. Jean, Jean P. Vincent, Vincent BBE, Laboratoire Microbiologie, Station Biologique, Roscoff, France Guezennec of Applied Microbiology, Volume...
Abstract The phylogenetic diversity of the gut microbial population hydrothermal shrimp Rimicaris exoculata was determined. presence micro-organisms in hindgut determined, and their morphology illustrated for first time by transmission electron microscopy. DNA extracted from fore-, mid- shrimps collected at Rainbow site, Mid-Atlantic Ridge, sequences small-subunit rRNA (16S rDNA) were analyzed. Seven different bacterial phylotypes identified 90 clones screened. affiliated to three major...
The Sonora Margin cold seeps present a seafloor mosaic pattern consisting of different faunal assemblages and microbial mats. To better understand if sedimentary communities reflect this patchy distribution, all major habitats were investigated using four complementary approaches: 16S rRNA 454 pyrosequencing, quantitative polymerase chain reaction, fluorescence in situ hybridization geochemistry analyses. This study reveals that sediments populated by surface show distinct porewater features...