0000000000432960
AUTHOR
Yves Dessaux
Additional file 3: of Transcriptome analysis revealed that a quorum sensing system regulates the transfer of the pAt megaplasmid in Agrobacterium tumefaciens
Mutagenesis of the quorum sensing determinants of pAtP4. All mutations were generated by the insertion of the same Gm resistance cassette that originated from p34S-Gm [39] either at the XbaI site of the cinI gene or at a reconstituted SphI site generated by the fusion of parts of cinR and cinX determinants in a synthetic ORF. (PDF 46Â kb)
Additional file 4: of Transcriptome analysis revealed that a quorum sensing system regulates the transfer of the pAt megaplasmid in Agrobacterium tumefaciens
The 32 differentially expressed genes identified by RNA-seq. Only changes above 3 fold with a p-value lower than 5 10 â 2 were considered significant. All differentially expressed genes were upregulated in P4 when compared to P4cinI. (PDF 285Â kb)
French collective expertise on herbicide-tolerant varieties
The primary objective in creating herbicide-tolerant varieties is to offer the farmers with an efficient tool to ensure weed control and solve weed problems, but their use could eventually have expected or unexpected consequences according to conditions of implementation. A few of those varieties, obtained either through classical breeding or through induced mutagenesis are now on the European market (especially oilseed rape and sunflower) while a majority, which was obtained through genetic engineering, is not allowed for cultivation in this area. The report describes how CNRS and INRA experts dealt with the scientific literature, extracts key elements, points out necessary watchfulness on…
Additional file 2: of Transcriptome analysis revealed that a quorum sensing system regulates the transfer of the pAt megaplasmid in Agrobacterium tumefaciens
UPLC MS-MS solvent composition. The table provides the composition of the solvent mixture used in the UPLC MS-MS analyses of the concentrated extract of the culture supernatant of strain P4. (DOCX 14Â kb)
3. Colloque Rhizosphère : programme et résumés des communications
National audience
Microbial ecology of the rhizosphere
Part II. Selected MethodsPlant-microbe Chapitre 9 : Interactions and Soil Quality; International audience
Acyl-homoserine lactone production is more common among plant-associated Pseudomonas spp. than among soilborne Pseudomonas spp.
ABSTRACT A total of 137 soilborne and plant-associated bacterial strains belonging to different Pseudomonas species were tested for their ability to synthesize N -acyl-homoserine lactones (NAHL). Fifty-four strains synthesized NAHL. Interestingly, NAHL production appears to be more common among plant-associated than among soilborne Pseudomonas spp. Indeed, 40% of the analyzed Pseudomonas syringae strains produced NAHL which were identified most often as the short-chain NAHL, N -hexanoyl- l -homoserine lactone, N -(3-oxo-hexanoyl)-homoserine lactone, and N -(3-oxo-octanoyl)- l -homoserine lactone (no absolute correlation between genomospecies of P. syringae and their ability to produce NAHL …
Rhizosphere: achievements and challenges
Reprinted from Plant and Soil, Vol.321, nos 1-2; International audience
Additional file 1: of Transcriptome analysis revealed that a quorum sensing system regulates the transfer of the pAt megaplasmid in Agrobacterium tumefaciens
Map of the genetic determinants involved in Ti plasmid conjugation in Agrobacterium strain C58. The functions of operons or genetic regions are as follows: acc, agrocinopine catabolism; arc, agrocinopine regulation of conjugation; noc, nopaline catabolism; tra, conjugative transfer region a; trb conjugative transfer region b; vir, virulence. Both the acc and arc operons are regulated by the repressor AccR. In the presence of agrocinopines A and B or in an accR mutant, the acc and arc operons are expressed. The expression of the arc operon permits the production of the QS regulator TraR. The production of the QS signal 3O,C8-HSL by the synthase TraI leads to an accumulation of the signal unt…
Les variétés végétales tolérantes aux herbicides, un outil de désherbage durable ?
Depuis 2009, des variétés de tournesol et de colza, dites « tolérantes aux herbicides » (TH), font leur apparition en France. Destinées à faciliter le désherbage, ces variétés résistent à un herbicide donné ce qui permet a priori d’appliquer l’herbicide sans risque pour la culture. La culture de telles variétés a suscité une contestation sociale se traduisant par l’arrachage de tournesols TH dénoncés comme « OGM cachés ». Dans ce contexte, les ministères chargés de l’Agriculture et de l’Environnement ont demandé à l’Inra et au CNRS de réaliser un bilan des connaissances disponibles sur l’ensemble des impacts de la culture de ces variétés.
Seasonal fluctuations and long-term persistence of pathogenic populations of Agrobacterium spp. in soils.
ABSTRACT Short- and long-term persistence of pathogenic (i.e., tumor forming) agrobacteria in soil was investigated in six nursery plots with a history of high crown gall incidence. No pathogenic Agrobacterium strains were isolated in soil samples taken in fall and winter in any plots, but such strains were isolated from both bulk soils and weed rhizospheres (over 0.5 × 10 5 pathogenic CFU/g of bulk soil or rhizosphere) in three out of six plots in spring and summer. PCR amplifications of a vir sequence from DNA extracted from soil confirmed the presence of Ti plasmids in summer and their absence in fall and winter. The results indicate that strains that harbor a Ti plasmid had an unforesee…
Transcriptome analysis revealed that a quorum sensing system regulates the transfer of the pAt megaplasmid in Agrobacterium tumefaciens.
Background Agrobacterium tumefaciens strain P4 is atypical, as the strain is not pathogenic and produces a for this species unusual quorum sensing signal, identified as N-(3-hydroxy-octanoyl)-homoserine lactone (3OH,C8-HSL). Results By sequence analysis and cloning, a functional luxI-like gene, named cinI, has been identified on the At plasmid of A. tumefaciens strain P4. Insertion mutagenesis in the cinI gene and transcriptome analyses permitted the identification of 32 cinI-regulated genes in this strain, most of them encoding proteins responsible for the conjugative transfer of pAtP4. Among these genes were the avhB genes that encode a type 4 secretion system (T4SS) involved in the forma…
Additional file 5: of Transcriptome analysis revealed that a quorum sensing system regulates the transfer of the pAt megaplasmid in Agrobacterium tumefaciens
Differentially expressed genes. Xlsx. Four repeats are show for the mutant strain P4cinI (col. B to E) with repetition numbers (e.g. rep1_cinI) and three repeats for the wild type strain P4 (col. F to H), also with repetition numbers (e.g. rep1_P4). Average values are given for the mutant strain P4cinI (col. I) and the wild type strain P4 (col. J). Fold change and Log2 fold change are also shown (col. K and L) along with the raw p values and adjusted p values (col. M and N). (XLSX 15Â kb)