Agricultural Microbes Genome 2 Conference Agricultural Microbes Genome 2 Conference
Session: Sequencing
S01_01.html
Ralstonia solanacearum is a Gram negative beta-proteobacterium. This plant pathogen has an unusually wide host range since it causes bacterial wilt disease in over 200 plant species belonging to more than 40 botanical families. Strain GMI1000 causes disease on various solanaceous crops, including potato, tomato and eggplant, and on the model plant Arabidopsis thaliana; it also induces a hypersensitive response after inoculation on tobacco. Its genome is composed of two replicons of 3.6 and 2.1 megabase pair as estimated from pulsed gel electrophoresis. Sequencing of the complete genome of this bacteria has been undertaken using a shotgun strategy. Nime equivalents of the genome have been sequenced permitting assembly of the data in two circular contigs having an average G+C% of 67. Analysis of the sequence indicates high local variations in the G+C content along the genome, ranging from 49% to over 72% for regions spanning over 1.5 kb. This heterogeneity is associated with the presence of numerous sequences sharing homology with genetically mobile elements, and suggests that numerous horizontal gene transfers might have occurred in this soil organism which displays natural competence for transformation by naked DNA. No clear pattern appears in the partitioning of these regions over the two replicons. The annotation of the sequence data shown that known pathogenicity genes are distributed on the two replicons and permitted the identification on new candidate genes for this function. A Blast server on the sequence is available at http://sequence.toulouse.inra.fr/R.solanacearum.