Project description:Pseudomonas aeruginosa is an opportunistic pathogen which causes acute and chronic infections that are difficult to treat. Comparative genomic analysis has showed a great genome diversity among P. aeruginosa clinical strains and revealed important regulatory traits during chronic adaptation. While current investigation of epigenetics of P. aeruginosa is still lacking, understanding the epigenetic regulation may provide biomarkers for diagnosis and reveal important regulatory mechanisms. The present study focused on characterization of DNA methyltransferases (MTases) in a chronically adapted P. aeruginosa clinical strain TBCF10839. Single-molecule real-time sequencing (SMRT-seq) was used to characterize the methylome of TBCF. RCCANNNNNNNTGAR and TRGANNNNNNTGC were identified as target motifs of DNA MTases, M.PaeTBCFI and M.PaeTBCFII, respectively.
Project description:Indole-3-acetic acid (IAA), knows as common plant hormone, is one of the most distributed indole derivatives in the environment. A novel strain, which was able to use IAA as sole source of carbon and nitrogen, was isolated from farm soil, identified and classified as Pseudomonas composti LY1 based on 16S rRNA sequence and genome analysis. The optimal growth conditions for LY1 with IAA are characterized. Proteome profile of strain LY1 to IAA and citrate were analyzed and compared using label free strategy with LC-MS/MS.
Project description:Purpose of study was to investigate whole genome expression changes of a strain with deletion of the two-component system TctD-TctE and determine genes dysregulate relative to the parental wildtype to gain insight into possible regulatory targets of TctD-TctE. TctD-TctE is a two-component system in Pseudomonas aeruginosa that responds to and regulates uptake of tricarboxylic acids such as citric acid. It accomplishes this through derepression of the porin encoding the gene opdH, thereby regulating influx of citrate metabolites from the surrounding environment. Deletion of the tctED operon (ΔtctED) resulted in a reduced growth phenotype when citric acid is present in media. In the ΔtctED strain the presence of citric acid was found to have an inhibitory effect on growth. When the alternative carbon source arginine was present, wildtype levels of growth could not be restored. Static cultures of ΔtctED had low cell density in the presence of citric acid but maintained the same levels of biofilm formation compared to conditions when no citric acid was present. This suggests a dysregulation of biofilm formation in the presence of citric acid. In the ΔtctED strain there was also greater accumulation of tobramycin within the biofilm compared to the PA14 wildtype strain. Additionally, analysis of whole-genome expression found that multiple metabolic genes were dysregulated in ΔtctED. Here it is concluded that TctD-TctE is involved in biofilm tolerance to tobramycin in the presence of citrate metabolites.
Project description:This study evaluates the transcriptome of Arabidopsis thaliana infected with the Pseudomonas syringae strain DC3000 cor- carrying the type three secretion system effector HopBB1
Project description:Relentless mining operations have destroyed our environment significantly. Soil inhabiting microbes play a significant role in ecological restoration of these areas. Microbial weathering processes like chemical dissolution of rocks significantly promotes the soil properties and enhances the rock to soil ratio respectively. Earlier studies have reported that bacteria exhibit efficient rock-dissolution abilities by releasing organic acids and other chemical elements from the silicate rocks. However, rock-dissolving mechanisms of the bacterium remain to be unclear till date. Thus, we have performed rock-dissolution experiments followed by genome and transcriptome sequencing of novel Pseudomonas sp.NLX-4 strain to explore the efficiency of microbe-mediated habitat restoration and its molecular mechanisms underlying this biological process. Results obtained from initial rock dissolution experiments revealed that Pseudomonas sp. NLX-4 strain efficiently accelerates the dissolution of silicate rocks by secreting amino acids, exopolysaccharides, and organic acids with elevated concentrations of potassium, silicon and aluminium elements. The rock dissolution experiments of NLX-4 strain exhibited an initial increase in particle diameter variation values between 0-15 days and decline after 15 days-time respectively. The 6,771,445-base pair NLX-4 genome exhibited 63.21 GC percentage respectively with a total of 6041 protein coding genes. Genome wide annotations of NLX-4 strain exhibits 5045-COG, 3996-GO, 5342-InterPro, 4386-KEGG proteins respectively Transcriptome analysis of NLX-4 cultured with/without silicate rocks resulted in 539 (288-up and 251-down) differentially expressed genes (DEGs). Fifteen DEGs encoding for siderophore transport, EPS and amino acids synthesis, organic acids metabolism, and bacterial resistance to adverse environmental conditions were highly up-regulated by cultured with silicate rocks. This study has not only provided a new strategy for the ecological restoration of rock mining areas, but also enriched the applicable bacterial and genetic resources.