A5081433370- Legume Nitrogen Fixing Symbiosis
- Plant nutrient uptake and metabolism
- Agronomic Practices and Intercropping Systems
- Nematode management and characterization studies
- Coastal wetland ecosystem dynamics
- Glycosylation and Glycoproteins Research
- Agricultural pest management studies
- Plant responses to water stress
- RNA and protein synthesis mechanisms
- Bacteriophages and microbial interactions
- Carbohydrate Chemistry and Synthesis
- Cassava research and cyanide
- Microbial Community Ecology and Physiology
- Peanut Plant Research Studies
- Microbial Metabolic Engineering and Bioproduction
- Plant Parasitism and Resistance
- Plant Stress Responses and Tolerance
- Bacterial Genetics and Biotechnology
- Immune Response and Inflammation
- Photosynthetic Processes and Mechanisms
- Protein Structure and Dynamics
- Protist diversity and phylogeny
- African Botany and Ecology Studies
- Neonatal Respiratory Health Research
- Plant Pathogenic Bacteria Studies
Laboratoire des Symbioses Tropicales et Méditerranéennes
2015-2024
Institut de Recherche pour le Développement
2015-2024
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
2020-2024
Centre de Coopération Internationale en Recherche Agronomique pour le Développement
2015-2024
Université de Montpellier
2017-2024
Centre Occitanie-Montpellier
2022-2024
Plant Health Institute de Montpellier
2022-2024
Institut Agro Montpellier
2014-2024
LMI Adaptation des Plantes et Microorganismes Associés aux Stress Environnementaux
2023
Centre National de la Recherche Scientifique
2003-2005
Here, we present a comparative analysis of the nodulation processes Aeschynomene afraspera and A. indica that differ in their requirement for Nod factors (NF) to initiate symbiosis with photosynthetic bradyrhizobia. The infection process nodule organogenesis was examined using green fluorescent protein–labeled Bradyrhizobium sp. strain ORS285 able nodulate both species. In indica, when NF-independent strategy is used, bacteria penetrated root intercellularly between axillary hairs invaded...
Nutritional symbiotic interactions require the housing of large numbers microbial symbionts, which produce essential compounds for growth host. In legume-rhizobium nitrogen-fixing symbiosis, thousands rhizobium microsymbionts, called bacteroids, are confined intracellularly within highly specialized host cells. Inverted Repeat-Lacking Clade (IRLC) legumes such as Medicago spp., bacteroids kept under control by an arsenal nodule-specific cysteine-rich (NCR) peptides, induce bacteria in...
Significance Legumes have a tremendous ecological and agronomic importance due to their ability interact symbiotically with nitrogen-fixing rhizobia. In most of the rhizobial–legume symbioses, establishment interaction requires plant perception bacterial lipochitooligosaccharide Nod factor signal. However, some bradyrhizobia can activate symbiosis differently, thanks type III secretion system, which delivers effector proteins into host cell. Here, we demonstrate that this symbiotic process...
Abstract Among legumes (Fabaceae) capable of nitrogen-fixing nodulation, several Aeschynomene spp. use a unique symbiotic process that is independent Nod factors and infection threads. They are also distinctive in developing root stem nodules with photosynthetic bradyrhizobia. Despite the significance these features, their understanding remains limited. To overcome such limitations, we conduct genetic studies nodulation evenia , supported by development genome sequence for A. transcriptomic...
We report the first use of tandem affinity purification (TAP) in a prokaryote to purify native protein complexes, and demonstrate its reliability power. purified acyl carrier (ACP) Escherichia coli , involved myriad metabolic pathways. Besides identification several known partners ACP, we rediscovered ACP/MukB ACP/IscS interactions already detected but previously disregarded as due contamination. Here, specificity these characterize them. This suggests that ACP is additional unsuspected...
Nitrogen fixation in the legume-rhizobium symbiosis is a crucial area of research for more sustainable agriculture. Our knowledge plant cascade response to perception bacterial Nod factors has increased recent years. However, discovery that are not involved Aeschynomene-Bradyrhizobium spp. interaction suggests alternative molecular dialogues may exist legume family. We evaluated conservation signaling pathway common other endosymbioses using three candidate genes: Ca2+/Calmodulin-Dependent...
Actinorhizal plants are able to establish a symbiotic relationship with Frankia bacteria leading the formation of root nodules. The interaction starts exchange signals in soil between plant and bacteria. This molecular dialogue involves signaling molecules that responsible for specific recognition host its endosymbiont. Here we studied two factors potentially involved casuarinae actinorhizal Casuarina glauca: (1) Root Hair Deforming Factor (CgRHDF) detected using test based on characteristic...
In prokaryotes, acyl carrier protein (ACP) is a cofactor central to myriad of syntheses, including fatty acid and phospholipid synthesis. To fulfill its function, ACP must therefore interact with multitude different enzymes, which includes the thioesterase YbgC. We found specific interaction between YbgC whose activity has been demonstrated in vitro on acyl-CoA derivatives, but physiological function bacteria remains unknown. Therefore, could be active some acyl-ACPs. then assigned ACP/YbgC...
The establishment of the rhizobium-legume symbiosis is generally based on plant perception Nod factors (NFs) synthesized by bacteria. However, some Bradyrhizobium strains can nodulate certain legume species, such as Aeschynomene spp. or Glycine max, independently NFs, and via two different processes that are distinguished necessity not a type III secretion system (T3SS). ErnA first known effector (T3E) triggering nodulation in indica. In this study, collection 196 sequenced was tested A....
Research on the nitrogen-fixing symbiosis has been focused, thus far, two model legumes, Medicago truncatula and Lotus japonicus, which use a sophisticated infection process involving thread formation. However, in 25% of bacterial entry occurs more simply an intercellular fashion. Among them, some Aeschynomene spp. are nodulated by photosynthetic Bradyrhizobium that do not produce Nod factors. This interaction is believed to represent living testimony ancestral state rhizobium-legume...
Legumes harbor in their symbiotic nodule organs nitrogen fixing rhizobium bacteria called bacteroids. Some legumes produce Nodule-specific Cysteine-Rich (NCR) peptides the cells to control intracellular bacterial population. NCR have antimicrobial activity and drive bacteroids toward terminal differentiation. Other do not are differentiated. Bradyrhizobia, infecting NCR-producing Aeschynomene plants, require peptide uptake transporter BclA cope with as well a specific peptidoglycan-modifying...
In response to the presence of compatible rhizobium bacteria, legumes form symbiotic organs called nodules on their roots. These house nitrogen-fixing bacteroids that are a differentiated bacteria. some legumes, bacteroid differentiation comprises dramatic cell enlargement, polyploidization, and other morphological changes. Here, we demonstrate peptidoglycan-modifying enzyme in Bradyrhizobium strains, DD-carboxypeptidase contains peptidoglycan-binding SPOR domain, is essential for normal...
Abstract The search for novel lipid A analogues from any biological source that can act as antagonists, displaying inhibitory activity towards the production of pro‐inflammatory cytokines, or immunomodulators in mammals, is a very topical issue. To this aim, structure and immunological properties lipopolysaccharide purple nonsulfur bacterium Rhodopseudomonas palustris strain BisA53 have been determined. This displays unique structural feature, with non‐phosphorylated skeleton made up...
Abstract Nod factors (NF) were assumed to be indispensable for the establishment of a rhizobium-legume symbiosis until discovery that certain Bradyrhizobium strains interacting with Aeschynomene species lack canonical nodABC genes required their synthesis. So far, molecular dialogue between and its symbionts remains an open question. Here we report time course transcriptional analysis evenia in response inoculation ORS278. The NF-independent symbiotic process was monitored at five points...
Acetobacter pasteurianus is an acetic acid-producing Gram-negative bacterium commonly found associated with plants and plant products widely used in the production of fermented foods, such as kefir vinegar. Due to acid conditions living habitat, uncommon structural features composing its cell envelope are expected. In present work we have investigated A. CIP103108 lipopolysaccharide (LPS) structure immunoactivity. The lipid A two different O-polysaccharides was assessed. Furthermore,...
Abstract The Bradyrhizobium vignae strain ORS3257 is an elite recommended for cowpea inoculation in Senegal. This was recently shown to establish symbioses on some Aeschynomene species using a cocktail of Type III effectors (T3Es) secreted by the T3SS machinery. In this study, collection mutants different T3Es genes, we sought identify that modulate symbiotic properties three Vigna ( V. unguiculata , radiata and mungo ). While had positive impact efficiency it blocked symbiosis with ....
In the most studied rhizobium-legume interactions, host plant supplies symbiont with homocitrate, an essential co-factor of nitrogenase enzyme complex, via expression a nodule-specific homocitrate synthase FEN1. Photosynthetic bradyrhizobia interacting Nod factor (NF) dependent and NF-independent Aeschynomene legumes are able to synthesize themselves as they contain nifV gene encoding synthase. Here, we show that in model strain ORS285, is required for free-living symbiotic dinitrogen...
Aeschynomene evenia has emerged as a new model legume for the deciphering of molecular mechanisms an alternative symbiotic process that is independent Nod factors.Whereas most research on nitrogen-fixing symbiosis, genetics and genomics so far focused Galegoid Phaseolid legumes, A. falls in more basal understudied Dalbergioid clade along with peanut (Arachis hypogaea).To provide insights into genes content structure genome, we established gene-based genetic map this species.Firstly, RNAseq...
To circumvent the paucity of nitrogen sources in soil legume plants establish a symbiotic interaction with nitrogen-fixing bacteria called rhizobia. During symbiosis, form root organs nodules, where are housed intracellularly and become active fixers known as bacteroids. Depending on their host plant, bacteroids can adopt different morphotypes, being either unmodified (U), elongated (E) or spherical (S). E- S-type undergo terminal differentiation leading to irreversible morphological changes...
In rhizobium strains, the lipid A is modified by addition of a very long chain fatty acid (VLCFA) shown to play an important role in rigidification outer membrane, thereby facilitating their dual life cycle, outside and inside plant. Bradyrhizobium more complex with presence at least two VLCFAs, one covalently linked hopanoid molecule, but importance these modifications not well understood. this study, we identified cluster VLCFA genes photosynthetic strain ORS278, which nodulates...
Bradyrhizobium are abundant soil bacteria and the major symbiont of legumes. The recent availability genome sequences provides a large source information for analysis symbiotic traits. In this study, we investigated evolutionary dynamics nodulation genes (nod) their relationship with encoding type III secretion systems (T3SS) effectors among bradyrhizobia. Based on comparative 146 sequences, identified six different types T3SS gene clusters. two predominant cluster designated RhcIa RhcIb...
Abstract Intensive research on nitrogen-fixing symbiosis in two model legumes has uncovered the molecular mechanisms, whereby rhizobial Nod factors activate a plant symbiotic signaling pathway that controls infection and nodule organogenesis. In contrast, so-called Nod-independent found between Aeschynomene evenia photosynthetic bradyrhizobia, which does not involve factor recognition nor thread formation, is less well known. To gain knowledge how established, we conducted phenotypic...