Project description:The purpose of this study was to define the TZD effect in Pseudomonas aeruginosa. Transcriptional profiling of Pseudomonas aeruginosa wild-type strain,reference strain PAO1, as control Vs. PAO1 strain exposed to a final 0.02mM of TZD derivative ((z)-5-octylidenethiazolidine-2,4-dione).
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. Overall design: A total of 8 samples were analyzed. Conditions of planktonic and biofilm growth were performed for both the tctED strain and wildtype (4 samples for each strain). Wildtype expression in this study was used as a basis to determine tctED expression relative to wildtype.
Project description:Pseudomonas chlororaphis strain 30-84 is an effective biological control agent against take-all disease of wheat. In this study, we conducted an RNA-seq analysis by comparing the wild type strain, PCA and O star with a phenazine deficient mutant. RNA-seq analysis identified over 800 genes differentially regulated by phenazines. Overall design: A total of 8 samples were analyzed in AB medium + 2% casamino acids, Pseudomonas chlororaphis wild type strain (2 replicates); Pseudomonas chlororaphis ZN mutant (2 replicates); Pseudomonas chlororaphis PCA strain (2 replicates); Pseudomonas chlororaphis O star (2 replicates).
Project description:Transcriptomic profiles of Pseudomonas protegens H78 and its (p)ppGpp0 relA/spoT mutant, which were grown to the late exponential phase (OD600 = 5.0 to 6.0) in the KMB media at 28 °C, were assessed by deep sequencing (RNA-seq) on Illumina 2500. Overall design: Two bacterial strains, Pseudomonas protegens H78 wild type strain and its (p)ppGpp0 mutant strain, each was replicated three times.
Project description:Representatives of two families of bacterial Par proteins, ParA and ParB, are encoded by the majority of bacterial chromosomes in the close vicinity of oriC. ParA(Soj) and ParB(Spo0J) proteins of Pseudomonas aeruginosa are both important for optimal growth, nucleoids segregation, cell division and different types of motility. Comparative transcriptome analysis of parAnull, parBnull mutants versus parental PAO1161 strain of P. aeruginosa demonstrated global changes in genes expression pattern in logarithmic phase of planktonic cultures grown on rich medium. The set of genes that were similarly regulated in both mutant strains as compared to the wild-type strain as well as two sets of genes uniquely affected in the particular mutant were defined suggesting that ParA and ParB may act in common and independently. In general, many genes involved in cell division, DNA and RNA processing and metabolic processes were down-regulated in mutant cells, in contrast genes which products play a role in adaptation, protection, motility, cell-to-cell signaling as well as signal transduction increased their expression in par mutant cells. Besides their role in chromosome segregation, ParA and ParB seem to have the potential to regulate genes transcription. The altered expression of a large number of genes encoding known or predicted transcriptional regulators and genes coding for products involved in c-di-GMP signalling, suggests that the part of observed global changes in genes expression pattern in parAnull and parBnull mutants might be the effect of indirect regulation mediated by regulatory genes under ParA and ParB control. The extended regulatory network provides the mechanism to modulate genes expression in response to the stage of the chromosome segregation process and cell cycle. Pseudomonas aeruginosa PAO1161 (leu, r-, RifR), derivative of PAO1, as a control (reference) strain, Pseudomonas aeruginosa PAO1161 parA1-40::smh (parAnull) and Pseudomonas aeruginosa PAO1161 parB1-18::TcR (parBnull) disruption mutant strains were used in the experiments. Three independent biological replicates of total RNA were isolated for each strain from logarithmic (Log) phase of planktonic culture grown on rich medium (L broth) at 37oC. In total, nine samples of RNA were prepared.