Table ronde. Le Nouveau Roman : passé, présent, futur

Les absents ont toujours tort et Jean Ricardou a dû en faire la douloureuse expérience à la suite de ce colloque-bilan intitulé « Three Decades of the French New Novel » qu’organise Tom Bishop avec Lois Oppenheim à l’université de New York du 30 septembre au 2 octobre 1982. Quoique physiquement absent, Ricardou se trouve pourtant au cœur de maints échanges pendant l’une des deux tables rondes de clôture qui réunit les romanciers Robert Pinget, Alain Robbe-Grillet, Nathalie Sarraute, Monique W..

La mort d’Oreste, de F. Pucciani

Hommage à F. Pucciani Parisinfo:eu-repo/semantics/publishe

Detection of potential transgenic plant DNA recipients among soil bacteria

The likelihood of gene transfer from transgenic plants to bacteria is dependent on gene number and the presence of homologous sequences. The large number of transgene copies in transplastomic (transgenes contained in the chloroplast genome) plant cells as well as the prokaryotic origin of the transgene, may thus significantly increase the likelihood of gene transfer to bacteria that colonize plant tissues. In order to assess the probability of such transfer, the length of homologous DNA sequences required between the transgene and the genome of the bacterial host was assessed. In addition, the probability that bacteria, which co-infect diseased plants, are transformable and have sequences similar to the flanking regions of the transgene was evaluated. Using Acinetobacter baylyi strain BD143 and transplastomic tobacco plants harboring the aadA gene (streptomycin and spectinomycin resistance), we found that sequences identical to the flanking regions containing as few as 55 nucleotides were sufficient for recombination to occur. Consequently, a collection of bacterial isolates able to colonize tobacco plant tissue infected by Ralstonia solanacearum strain K60 was obtained, screened for DNA sequence similarity with the chloroplastic genes accD and rbcL flanking the transgene, and tested for their ability to uptake extracellular DNA (broad host-range pBBR1MCS plasmids) by natural or electro-transformation. Results showed that among the 288 bacterial isolates tested, 8% presented DNA sequence similarity with one or both chloroplastic regions flanking the transgene. Two isolates, identified as Pseudomonas sp. and Acinetobacter sp., were able to integrate exogenous plasmid DNA by electro-transformation and natural transformation, respectively. Our data suggest that transplastomic plant DNA recipients might be present in soil bacterial communities