Project description:Pseudomonas aeruginosa is a virulent opportunistic pathogen responsible for high morbity in COPD, burns , implanted medical devices and cystic fibrosis. Pseudomonas aeruginosa is a problematic colonizer of the human lung. P. aeruginosa produces a phospholipase C (PlcH) that degrades choline-containing lipids such as phosphatidylcholine and sphingomylein that are found in lung surfactant and in host membranes. In this study, we analyzed gene expression in mutants defective in PlcH production (delta-plcH and delta-gbdR) and the wild type when growing in medium with lung surfactant. Pseudomonas aeruginosa was cultured in liquid cultures with aeration in a defined medium with Survanta, a lung surfactant replacement. Cultures were harvested during mid-exponential phase, and RNA was isolated for microarray analysis. The P. aeruginosa strain PAO1 wild type gene expression was compared to expression profiles from delta-gbdR and delta-plcHR deletion mutants, two mutants defective in PlcH production.
Project description:Pseudomonas aeruginosa is a virulent opportunistic pathogen responsible for high morbity in COPD, burns , implanted medical devices and cystic fibrosis. Pseudomonas aeruginosa is a problematic colonizer of the human lung. P. aeruginosa produces a phospholipase C (PlcH) that degrades choline-containing lipids such as phosphatidylcholine and sphingomylein that are found in lung surfactant and in host membranes. In this study, we analyzed gene expression in mutants defective in PlcH production (delta-plcH and delta-gbdR) and the wild type when growing in medium with lung surfactant.
Project description:The aim of the experiment was to assay every gene in the Escherichia coli genome to identify those that contribute to competition with Pseudomonas aeruginosa. A library of transposon-insertion mutants was grown overnight either alone or together with an equal starting number of P. aeruginosa cells. The experiment was also conducted in the presence or absence of glucose to interrogate the effect of a plentiful supply of carbon source. DNA sequencing was then used to reveal the locations of the transposons in every mutant. By comparing the numbers of each mutant between conditions, information can be gained about the relative fitness of that mutant under the conditions tested.
Project description:Analysis of a SigX knockout mutant of Pseudomonas aeruginosa H103 strain in minimal medium with glucose as carbon source (M9G). SigX, one of the 19 extra-cytoplasmic function sigma factors of P. aeruginosa, was only known to be involved in transcription of the gene encoding the major outer membrane protein OprF in Pseudomonas aeruginosa. Deletion of the ECF sigma factor sigX gene provide insights into the SigX role in several virulence and biofilm- related phenotypes in Pseudomonas aeruginosa.
Project description:The ParS/ParR two component regulatory system plays important roles for multidrug resistance in Pseudomonas aeruginosa. In this study we report RNA-seq analyses of the transcriptomes of P. aeruginosa PAO1 wild type and par mutants growing in a minimal medium containing 2% casamino acids. This has allowed the quantification of PAO1 transcriptome, and further defines the regulon that is dependent on the ParS/ParR system for expression. Our RNA-seq analysis produced the first estimates of absolute transcript abundance for the 5570 coding genes in P. aeruginosa PAO1. Comparative transcriptomics of P. aeruginosa PAO1 and par mutants identified a total of 464 genes regulated by ParS and ParR. Results also showed that mutations in the parS/parR system abolished the expression of the mexEF-oprN operon by down-regulating the regulatory gene mexS. In addition to affecting drug resistance genes, transcripts of quorum sensing genes (rhlIR and pqsABCDE-phnAB), were significantly up-regulated in both parS and parR mutants. Consistent with these results, a significant portion of the ParS/ParR regulated genes belonged to the MexEF-OprN and quorum sensing regulons. Deletion of par genes also lead to overproduction of phenazines and increased swarming motility, consistent with the up-regulation of quorum sensing genes. Our results established a link among ParS/ParR, MexEF-OprN and quorum sensing in Pseudomonas aeruginosa. Based on these results, we propose a model to illustrate the relationship among these regulatory systems in P. aeruginosa. A total of 9 samples were analyzed in AB medium + 2% casamino acids, Pseudomonas aeruginosa PAO1 wild type strain (3 replicates); Pseudomonas aeruginosa parS mutant (3 replicates); Pseudomonas aeruginosa parR mutant (3 replicates).
Project description:Analysis of a SigX knockout mutant of Pseudomonas aeruginosa H103 strain in minimal medium with glucose as carbon source (M9G). SigX, one of the 19 extra-cytoplasmic function sigma factors of P. aeruginosa, was only known to be involved in transcription of the gene encoding the major outer membrane protein OprF in Pseudomonas aeruginosa. Deletion of the ECF sigma factor sigX gene provide insights into the SigX role in several virulence and biofilm- related phenotypes in Pseudomonas aeruginosa. To better understand the cellular function of SigX, a deletion mutant of the sigX gene (PAOSX) was generated and its expression profile was compared with parental strain Pseudomonas aeruginosa H103. To this end, H103 and a sigX mutant were cultured in M9G, in which their growth are similar. Three independant biological replicate were taken for the RNA extraction and hybridization on affymetrix array in the middle of the exponential growth phase.
Project description:ErfA is a transcription factor of Pseudomonas aeruginosa. We here define the genome-wide binding sites of ErfA by DAP-seq in Pseudomonas aeruginosa PAO1 and IHMA87, Pseudomonas chlororaphis PA23, Pseudomonas protegens CHA0 and Pseudomonas putida KT2440.
Project description:Transcriptional profiling in Pseudomonas aeruginosa MPAO1 and its glyoxylate shunt gens transposon insertion mutants (aceA and glcB) was perfomed using microarray analysis with or without 1mM PQ treatment. Based on the gene expression, we investigated role of glyoxylate shunt in P. aeruginosa and found out pathway related with glyoxylate shunt under oxidative stress.
Project description:Pseudomonas aeruginosa and Staphylococcus aureus are often co-isolated in persistent infections. The goal of this study was to determine how secreted products from S. aureus affect gene expression in P. aeruginosa. Therefore, media control or S. aureus supernatant was added to P. aeruginosa cultures at 25% total volume and gene expression was measured at 20 min, 1 h, and 2 h using RNA-seq. Overall, after addition of S. aureus supernatant, there was an upregulation in genes involved in metal deprivation and intermediate metabolite uptake.