A5043621822- Metalloenzymes and iron-sulfur proteins
- Plant Pathogenic Bacteria Studies
- Bacterial Genetics and Biotechnology
- Legume Nitrogen Fixing Symbiosis
- Trace Elements in Health
- Microbial Fuel Cells and Bioremediation
- Enzyme Production and Characterization
- Plant-Microbe Interactions and Immunity
- Antibiotic Resistance in Bacteria
- Metal-Catalyzed Oxygenation Mechanisms
- Enzyme Structure and Function
- Escherichia coli research studies
- Biofuel production and bioconversion
- RNA and protein synthesis mechanisms
- Redox biology and oxidative stress
- Photosynthetic Processes and Mechanisms
- Genomics and Phylogenetic Studies
- Porphyrin Metabolism and Disorders
- RNA modifications and cancer
- Microbial Community Ecology and Physiology
- Coenzyme Q10 studies and effects
- Vibrio bacteria research studies
- Microbial Metabolic Engineering and Bioproduction
- Mitochondrial Function and Pathology
- Metal Extraction and Bioleaching
Institut Pasteur
2018-2025
Centre National de la Recherche Scientifique
2015-2024
Université Paris Cité
2021-2024
Laboratoire de Chimie Bactérienne
2012-2021
Institut de Microbiologie de la Méditerranée
2009-2021
Aix-Marseille Université
2010-2019
In-Q-Tel
2011
University of Lausanne
2009
Institut de Biologie Structurale
1997-2005
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
1997-2005
Historically the genus Erwinia has served as a repository for plant-pathogenic or plant-associated bacteria (25, 96, 128). Consequently, diverse that occupy different habitats on within plants and plant remains have been lumped into this genus. Their diversity is also reflected in range of symp toms, i.e. necrosis, wilts, galls, rots elicited wide plants. This notwithstanding, these are related genetically to other en terobacteria such Escherichia coli Salmonella typhimurium well model...
All bactericidal antibiotics were recently proposed to kill by inducing reactive oxygen species (ROS) production, causing destabilization of iron-sulfur (Fe-S) clusters and generating Fenton chemistry. We find that the ROS response is dispensable upon treatment with antibiotics. Furthermore, we demonstrate Fe-S are required for killing only aminoglycosides. In contrast cells, using major cluster biosynthesis machinery, ISC, cells alternative SUF, cannot efficiently mature respiratory...
Oxidation of methionine residues to sulfoxide can lead inactivation proteins. Methionine reductase (MsrA) has been known for a long time, and its repairing function well characterized. Here we identify new reductase, which referred as MsrB, the gene is present in genomes eubacteria, archaebacteria, eucaryotes. The msrA msrB genes exhibit no sequence similarity and, some genomes, are fused. Escherichia coli MsrB protein (currently predicted be encoded by an open reading frame unknown named...
Biosynthesis of iron-sulfur clusters (Fe-S) depends on multiprotein systems. Recently, we described the SUF system Escherichia coli and Erwinia chrysanthemi as being important for Fe-S biogenesis under stressful conditions. The is made six proteins: SufC an atypical cytoplasmic ABC-ATPase, which forms a complex with SufB SufD; SufA plays role scaffold protein assembly delivery to target proteins; SufS cysteine desulfurase mobilizes sulfur atom from provides it cluster; SufE has no associated...
The phylogenetic diversity of prokaryotic communities exposed to arid conditions in the hot desert Tataouine (south Tunisia) was estimated with a combination culture and - molecular-based analysis. Thirty-one isolates, representative each dominant morphotypes, were affiliated Actinobacteria, Firmicutes, Proteobacteria CFB group while none related Archaea. Analysis 16S rRNA gene libraries revealed presence species Bacteria Sequences Archaea all non-thermophilic Crenarchaeota subgroup....
Erwinia chrysanthemi produced several pectate lyases (EC 4.2.2.2) and endocellulases 3.2.1.4) which were largely secreted into the culture medium. Mutants deficient in secretion mechanism for these enzymes obtained by chemical insertion mutagenesis. Further study of one such mutant revealed that both enzyme activities retained simultaneously within periplasmic space.
Cobalt is toxic for cells, but mechanisms of this toxicity are largely unknown. The biochemical and genetic experiments reported here demonstrate that iron-sulfur proteins greatly affected in cobalt-treated Escherichia coli cells. Exposure a wild-type strain to intracellular cobalt results the inactivation three selected enzymes, tRNA methylthio-transferase, aconitase, ferrichrome reductase. Consistently, mutant strains lacking [Fe-S] cluster assembly SUF machinery hypersensitive cobalt....
Iron sulfur (Fe/S) proteins are ubiquitous and participate in multiple biological processes, from photosynthesis to DNA repair. highly reactive chemical species, the mechanisms allowing multiprotein systems ISC SUF assist Fe/S cluster formation vivo have attracted considerable attention. Here, A-Type components of these (ATCs for Carriers) studied by phylogenomic genetic analyses. ATCs that emerged last common ancestor bacteria were conserved most acquired eukaryotes few archaea via...
Salmonella enterica serovar Typhimurium is an intracellular pathogen that can survive and replicate within macrophages. One of the host defense mechanisms encounters during infection production reactive oxygen species by phagocyte NADPH oxidase. Among them, hydrogen peroxide (H(2)O(2)) diffuse across bacterial membranes damage biomolecules. Genome analysis allowed us to identify five genes encoding H(2)O(2) degrading enzymes: three catalases (KatE, KatG, KatN) two alkyl hydroperoxide...
Transfer RNA molecules have been recently recognized as widespread targets of bacterial immune systems. Translation inhibition through tRNA cleavage or modification inhibits phage propagation, thereby protecting the population. To counteract this, some viruses encode their own molecules, allowing infection to take place. The AriB effector PARIS defence system is a Toprim nuclease previously shown target E. coli tRNALys(UUU), but not tRNALys(UUU) variant encoded by bacteriophage T5. We...
Erwinia chrysanthemi causes soft‐rot disease in a great variety of plants. In addition to the depolymerizing activity plant cell wall‐degrading enzymes, iron acquisition and resistance oxidative stress contribute greatly virulence this pathogen. Here, we studied pin10 locus originally thought encode new factors. The sequence analysis revealed six open reading frames that were homologous Escherichia coli sufA , sufB sufC sufD sufS sufE genes. Sequence similarity searching predicted (i) SufA,...
Peptide methionine sulfoxide reductase (MsrA), which repairs oxidized proteins, is present in most living organisms, and the cognate structural gene belongs to so-called minimum set [Mushegian, A. R. & Koonin, E. V., (1996) Proc. Natl. Acad. Sci. USA 93, 10268–10273]. In this work, we report that MsrA required for full virulence of plant pathogen Erwinia chrysanthemi . The following differences were observed between wild-type a − mutant: ( i ) mutant was more sensitive oxidative stress;...