A5024808760- Microbial Community Ecology and Physiology
- Wastewater Treatment and Nitrogen Removal
- Genomics and Phylogenetic Studies
- Marine and coastal ecosystems
- Microbial bioremediation and biosurfactants
- Methane Hydrates and Related Phenomena
- Bacterial Genetics and Biotechnology
- Coastal wetland ecosystem dynamics
- Microbial Metabolic Engineering and Bioproduction
- Marine Biology and Ecology Research
- Protist diversity and phylogeny
- Enzyme Structure and Function
- Marine and coastal plant biology
- Microbial Fuel Cells and Bioremediation
- Geochemistry and Elemental Analysis
- Soil and Water Nutrient Dynamics
- Hydrocarbon exploration and reservoir analysis
- Atmospheric and Environmental Gas Dynamics
- Marine Bivalve and Aquaculture Studies
- RNA and protein synthesis mechanisms
- Environmental DNA in Biodiversity Studies
- Algal biology and biofuel production
- Enzyme Production and Characterization
- Mycorrhizal Fungi and Plant Interactions
- Metabolomics and Mass Spectrometry Studies
Institut Méditerranéen d’Océanologie
2014-2024
Université de Toulon
2012-2024
Aix-Marseille Université
2012-2024
Institut de Recherche pour le Développement
2012-2024
Centre National de la Recherche Scientifique
2011-2024
Laboratoire de Biotechnologie et Chimie Marines
2005-2019
Institut de Microbiologie de la Méditerranée
2010-2012
Centre d’Immunologie de Marseille-Luminy
1997-2011
Station Marine d'Endoume
1995-2010
Maya Educational Foundation
2010
ABSTRACT Two PCR primer sets were developed for the detection and quantification of cytochrome cd 1 -denitrifying bacteria in environmental marine samples. The specificity sensitivity these primers tested. Both suitable detection, but only one set, cd3F–cd4R, was enumeration functional community using most-probable-number competitive techniques. Quantification denitrifiers taken from sediment water samples achieved two different molecular techniques which target nirS gene, results compared...
Two rpoN-linked ΔTn10-kan insertions suppress the conditionally lethal erats allele. One truncates rpoN while second disrupts another gene (ptsN) in operon and does not affect classical nitrogen regulation. Neither alter expression of era indicating that suppression is post-translational. Plasmid clones ptsN prevent by either disruption mutation this important for lethality caused erats. six neighboring genes were sequenced compared with sequences database. these encode proteins homologous...
Earlier observations in mangrove sediments of Goa, India have shown denitrification to be a major pathway for N loss1. However, percentage total nitrate transformed through complete accounted <0–72% the pore water reduced. Here, we show that up 99% removal is routed dissimilatory reduction ammonium (DNRA). The DNRA process was 2x higher at relatively pristine site Tuvem compared anthropogenically-influenced Divar ecosystem. In systems receiving low extraneous nutrient inputs, this mechanism...
Since 2011, massive new strandings of holopelagic Sargassum have been reported on the coasts Caribbean, northern Brazil, Guiana, and West Africa, causing severe economic ecological damage. Three common morphotypes (S. fluitans III, S. natans I, VIII) were identified as responsible for these catastrophic events, with dominance shifts between them over time. However, taxonomic status remains unclear. Using an integrative taxonomy framework, combining a morphological study molecular analyses,...
Summary The Escherichia coli fructose repressor, FruR, is known to regulate expression of several genes concerned with carbon utilization. Using a previously derived consensus sequence for FruR binding, additional potential operators were identified and tested binding in DNA band migration retardation assays. Operators the control regions operons metabolism bound while those not did not. In vivo assays transcriptional lacZ fusions showed that controls operator‐containing encoding key enzymes...
To appreciate differences in benthic bacterial community composition at the relatively pristine Tuvem and anthropogenically-influenced Divar mangrove ecosystems Goa, India, parallel tag sequencing of V6 region 16S rDNA was carried out. We hypothesize that availability extraneously-derived anthropogenic substrates could act as a stimulatant but not deterrent to promote higher diversity Divar. Our observations revealed phylum Proteobacteria dominant both locations comprising 43-46% total tags....
The temperate Northwest Pacific brown alga Rugulopteryx okamurae (Dictyotales, Phaeophyceae) was first discovered in 2002 the Mediterranean Sea Thau coastal lagoon (Occitania, France) and then again 2015 along southern side of Strait Gibraltar, where it assigned with invasive status. We report here on occurrence species Calanques National Park (Marseille, 2018. By 2020, a large population had developed, extending over 9.5 km coastline, including highly protected no-take zones. seafood trade,...
Net nitrous oxide production and denitrification activity were measured in two mangrove ecosystems of Goa, India. The relatively pristine site Tuvem was compared to Divar, which is prone high nutrient input. Stratified sampling at 2‐cm intervals within the 0‐ 10‐cm depth range showed that N 2 O both locations decreased with depth. Elevated Divar resulted maximum up 1.95 nmol O‐N g −1 h 4 cm, three times higher than Tuvem. Detailed investigations understand major pathway contributing...
Marinobacter hydrocarbonoclasticus SP17 forms biofilms specifically at the interface between water and hydrophobic organic compounds (HOCs) that are used as carbon energy sources. Biofilm formation HOC-water has been recognized a strategy to overcome low availability of these nearly water-insoluble substrates. Here, we present genome sequence SP17, which could provide further insights into mechanisms enhancement HOCs assimilation through biofilm formation.
An anaerobic, thermophilic, filamentous (0.45 × >100 µm) bacterium, designated D1-25-10-4 T , was isolated from a deep hot aquifer in France. Cells were non-motile and Gram-negative. Growth observed at 43–65 °C (optimum 55 °C), pH 6.8–7.8 7.0) with 0–5 g NaCl l −1 0 ). Strain chemo-organotroph fermented ribose, maltose, glucose, galactose, arabinose, fructose, mannose, sucrose, raffinose, xylose, glycerol, fumarate, peptone, starch xylan. Yeast extract required for growth. Sulfate,...
Abstract. Diazotrophic activity and primary production (PP) were investigated along two transects (Belgica BG2014/14 GEOVIDE cruises) off the western Iberian Margin Bay of Biscay in May 2014. Substantial N2 fixation was observed at 8 10 stations sampled, ranging overall from 81 to 384 µmol N m−2 d−1 (0.7 8.2 nmol L−1 d−1), with sites close situated between 38.8 40.7∘ yielding rates reaching up 1355 1533 d−1. Primary relatively lower Margin, 33 59 mmol C d−1, while it increased towards...
Abstract Since 2011, the Caribbean coasts have been subject to episodic influxes of floating Sargassum seaweed unprecedented magnitude originating from a new area “the Great Atlantic Belt” (GASB), leading in and mass strandings Sargassum. For biofilm both holopelagic benthic as well surrounding waters, we characterized main functional groups involved microbial nitrogen cycle. The abundance genes representing fixation (nifH), nitrification (amoA), denitrification (nosZ) showed predominance...
Two novel Gram-negative bacteria, designated strains DR41_21T and DR41_18T, were isolated from coastal, surface waters of the north-western Mediterranean Sea. The cells motile, pleomorphic rods, 2.9 μm long 0.9 wide formed cream colonies on marine agar medium. G+C content genomic DNA was 60 mol%. Phylogenetic analysis 16S rRNA gene sequences positioned isolates in class Alphaproteobacteria within family Rhodospirillaceae. sequence similarity two 98.8 % but DNA–DNA hybridization indicated...