A5076593442- Genomics and Phylogenetic Studies
- Microbial Community Ecology and Physiology
- RNA and protein synthesis mechanisms
- Bacteriophages and microbial interactions
- Protist diversity and phylogeny
- Bacterial Genetics and Biotechnology
- Methane Hydrates and Related Phenomena
- Enzyme Structure and Function
- DNA and Nucleic Acid Chemistry
- Genomics and Chromatin Dynamics
- DNA Repair Mechanisms
- Cancer therapeutics and mechanisms
- Paleontology and Stratigraphy of Fossils
- Glycosylation and Glycoproteins Research
- Trace Elements in Health
- Marine and environmental studies
- Antimicrobial Peptides and Activities
- Heavy metals in environment
- Hydrocarbon exploration and reservoir analysis
- Enzyme Production and Characterization
- Chromium effects and bioremediation
- Legume Nitrogen Fixing Symbiosis
- Plant Genetic and Mutation Studies
- Peptidase Inhibition and Analysis
- Polyamine Metabolism and Applications
Centre National de la Recherche Scientifique
2008-2021
Université Paris-Saclay
2016-2021
CEA Paris-Saclay
2021
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2021
Institut de Biologie Intégrative de la Cellule
2016-2021
Université Paris-Sud
2008-2017
Université Paris Cité
1986-2002
University of Copenhagen
2001
University of Ottawa
2001
Institute for Marine Biosciences
2001
The genome of the crenarchaeon Sulfolobus solfataricus P2 contains 2,992,245 bp on a single chromosome and encodes 2,977 proteins many RNAs. One-third encoded have no detectable homologs in other sequenced genomes. Moreover, 40% appear to be archaeal-specific, only 12% 2.3% are shared exclusively with bacteria eukarya, respectively. shows high level plasticity 200 diverse insertion sequence elements, putative nonautonomous mobile evidence integrase-mediated events. There also long clusters...
Abstract Background Thermococcus gammatolerans was isolated from samples collected hydrothermal chimneys. It is one of the most radioresistant organisms known amongst Archaea. We report determination and annotation its complete genome sequence, comparison with other Thermococcales genomes, a proteomic analysis. Results T. has circular chromosome 2.045 Mbp without any extra-chromosomal elements, coding for 2,157 proteins. A thorough comparative genomics analysis revealed important but...
The Candidate Phyla Radiation (CPR) constitutes a large group of mostly uncultured bacterial lineages with small cell sizes and limited biosynthetic capabilities. They are thought to be symbionts other organisms, but the nature this symbiosis has been ascertained only for cultured Saccharibacteria, which epibiotic parasites bacteria. Here, we study biology genome Vampirococcus lugosii, becomes first described species Vampirococcus, genus bacteria morphologically identified decades ago....
The hyperthermophilic euryarchaeon Pyrococcus abyssi and the related species furiosus horikoshii, whose genomes have been completely sequenced, are presently used as model organisms in different laboratories to study archaeal DNA replication gene expression develop genetic tools for hyperthermophiles. We performed an extensive re-annotation of genome P. obtain integrated view its phylogeny, molecular biology physiology. Many new functions predicted both informational operational proteins....
Cultivable archaeal species are assigned to two phyla -- the Crenarchaeota and Euryarchaeota by a number of important genetic differences, this ancient split is strongly supported phylogenetic analysis. The recently described hyperthermophile Nanoarchaeum equitans, harboring smallest cellular genome ever sequenced (480 kb), has been suggested as representative new phylum Nanoarchaeota that would have diverged before Crenarchaeota/Euryarchaeota split. Confirming position N. equitans thus...
Horizontal gene transfer (HGT) is an important force in evolution, which may lead, among other things, to the adaptation new environments by import of metabolic functions. Recent studies based on phylogenetic analyses a few genome fragments containing archaeal 16S rRNA genes and fosmid-end sequences from deep-sea metagenomic libraries have suggested that marine planktonic archaea could be affected high HGT frequency. Likewise, composite uncultured euryarchaeote showed levels sequence...
ABSTRACT Bacteriophage T5 represents a large family of lytic Siphoviridae infecting Gram-negative bacteria. The low-resolution structure showed the T=13 geometry capsid and unusual trimeric organization tail tube, assembly pathway was established. Although major structural proteins have been identified in these studies, most genes encoding morphogenesis remained to be identified. Here, we combine proteomic analysis particles with bioinformatic study electron microscopic immunolocalization...
Cyanobacteria are thought to play a key role in carbonate formation due their metabolic activity, but other organisms carrying out oxygenic photosynthesis (photosynthetic eukaryotes) or metabolisms (e.g. anoxygenic photosynthesis, sulfate reduction), may also contribute formation. To obtain more quantitative information than that provided by classical PCR-dependent methods, we studied the microbial diversity of microbialites from Alchichica crater lake (Mexico) mining for 16S/18S rRNA genes...
Microviridae, a family of bacteria-infecting ssDNA viruses, is member the still poorly characterized bacteriophages, even though they include phage PhiX174, one main models in virology for genomic and capsid structure studies. Recent studies suggest that are diverse well represented marine freshwater virioplankton as human microbiomes. Despite previous knowledge, their diversity, abundance ecological role completely unknown soil ecosystems. Here we present comparative analysis 17 assembled...
A unicellular cyanobacterium, strain Alchichica-D10, was isolated from microbialites of the alkaline Lake Alchichica, Mexico. The cells were short rods (3.9±0.6 µm in length and 1.1±0.1 width) forming biofilms intense emerald green colour. They exhibited red autofluorescence under UV light excitation. UV-visible absorption spectra revealed that they contain chlorophyll a phycocyanin, electron microscopy showed presence thylakoids. grew within temperature range 15-30 °C. Genomic DNA G+C...
The plasmid pGT5 (3,444 bp) from the hyperthermophilic archaeon Pyrococcus abyssi GE5 has been completely sequenced. Two major open reading frames with a good coding probability are located on same strand and cover 85% of total sequence. larger frame encodes putative polypeptide which exhibits sequence similarity Rep proteins plasmids using rolling-circle mechanism for replication. Upstream this frame, we have detected an 11-bp motif identical to double-stranded origin several bacterial that...
The genomes of three Pyrococcus species, P.abyssi, P.furiosus and P.horikoshii, were compared at the DNA level, taking advantage our identification their replication origins. Three types rearrangements have been identified: (i) inversion translation across axis (origin/terminus), (ii) translocation restricted to a replichore (the half chromosome divided by axis) (iii) apparent mobility long clusters repeated sequences. Rearrangements within more common between two other species than...
ABSTRACT Our understanding of the genetics species best-studied hyperthermophilic archaea, Pyrococcus spp . , is presently limited by lack suitable genetic tools, such as a stable cloning vector and ability to select individual transformants on plates. Here we describe development reliable host-vector system for archaeon abyssi Shuttle vectors were constructed based endogenous plasmid pGT5 from P. strain GE5 bacterial pLitmus38. As no antibiotic resistance marker currently available spp.,...
Modern microbialites are often used as analogs of Precambrian stromatolites; therefore, studying the metabolic interplay within their associated microbial communities can help formulating hypotheses on formation and long-term preservation fossil record. We performed a comparative metagenomic analysis microbialite samples collected at two sites along depth gradient in Lake Alchichica (Mexico). The community structure inferred from single-copy gene family identification long-contig (>10 kb)...
Acidobacteria constitute a still poorly studied phylum that is well represented in soils. Recent studies suggest members of this may be also abundant deep-sea plankton, but their relative abundance and ecological role ecosystem are completely unknown. A recent screening three metagenomic libraries bathypelagic plankton from the South Atlantic (1000 m depth), Adriatic depth) Ionian (3000 seas Mediterranean revealed an unexpected proportion acidobacterial fosmids, which affiliated to...