Identification of genes involved with P. aeruginosa biofilm antibiotic resistance by microarray analysis
ABSTRACT: Microarray analysis was used to identify changes in the level of transcription of genes in P. aeruginosa drip flow biofilms in response to ciprofloxacin and tobramycin exposure. This data was evaluated and used to select strains that carry transposon mutations in genes that might play a role in antibiotic tolerance of biofilms. The strains were evaluated for defects in biofilm tolerance. Four drip flow biofilm conditions with three replicates each: (1) baseline controls at 72 hours, (2) tobramycin treated for 12 hours past baseline, (3) ciprofloxacin treated for 12 hrs past baseline, and (4) no treatment for 12 hrs past baseline.
Project description:Abstract: Transcriptome analysis was applied to characterize the physiological activities of Pseudomonas aeruginosa grown for three days in drip-flow biofilm reactors. Conventional applications of transcriptional profiling often compare two paired data sets that differ in a single experimentally controlled variable. In contrast this study obtained the transcriptome of a single biofilm state, ranked transcript signals to make the priorities of the population manifest, and compared rankings for a priori identified physiological marker genes between the biofilm and published data sets. Two drip flow biofilm conditions with three replicates each: (1) baseline control at 72hrs, (2) no treatment for 12 hours past baseline. Data from these two conditions were pooled
Project description:Transcriptome analysis was applied to characterize the physiological activities of Psuedomonas aeruginosa cells grown for three days in drip flow biofilm reactors when compared to the activities of P. aeruginosa grown planktonically to exponential phase in the same media. Here, rather than examining the effect of an individual gene on biofilm antibiotic tolerance, we used a transcriptomics approach to identify regulons and groups of related genes that are induced during biofilm growth of Pseudomonas aeruginosa. We then tested for statistically significant overlap between the biofilm-induced genes and independently compiled gene lists corresponding to stress responses and other putative antibiotic protective mechanisms. This data was evaluated and used to select strains that carry transposon mutations in genes that might play a role in antibiotic tolerance of biofilms. The strains were evaluated for defects in biofilm tolerance. One planktonic condition with four biological replicates; One drip flow biofilm condition grown for 72 hours with three biological replicates; One drip flow biofilm condition grown for 84 hours with three biological replicates.
Project description:We grew Pseudomonas aeruginosa biofilms on CFBE41o- human airway cells in culture, and we treated these biofilms with tobramycin. Microarray analysis was performed to gain an understanding of the global transcriptional changes that occur during antibiotic treatment. Experiment Overall Design: We compared three untreated control samples with three tobramycin-treated samples. Biofilms were grown on CFBE41o- cells in culture for 9 hours in MEM/0.4% arginine. Replicate samples were then incubated in the presence or absence of 500 μg/mL tobramycin for 30 minutes.
Project description:This SuperSeries is composed of the following subset Series:; GSE9989: Tobramycin Treatment of P. aeruginosa Biofilms Grown on CFBE41o- Cells; GSE9991: Tobramycin Treatment of Planktonic Pseudomonas aeruginosa Experiment Overall Design: Refer to individual Series
Project description:LD13 mutant was considered for this analysis since it generated mushroom-type mature biofilm. This strain looses 17.6% of parental chromosome and lacks of several bacterial surface structures/genes but still has some novel autoaggregation genes. The global gene-expression profiles of LD13 flow-cell biofilm were compared after 24, 48, 72, 96, and 144 hr, respectively, as well as with those of LD13 planktonic cultures.
Project description:Burkholderia cenocepacia J2315 biofilms were described to have an increased susceptibility towards tobramycin when baicalin hydrate was added to the treatment. The goal of this transcriptomic analysis is to elucidate the effect of baicalin hydrate on gene expression levels when added to tobramycin treatment. Therefore, biofilms were grown for 24 hours and treated for another 24 hours with either tobramycin (TOB) (1024ug/ml), baicalin hydrate (BH) (250uM) or a combination of both. Also, an untreated control (physiological saline) was included. This experiment was repeated twice, so three biological replicates per treatment were included for RNAsequencing.
Project description:As a comparison to tobramycin-treated P. aeruginosa biofilms, we investigated the response of planktonic P. aeruginosa to tobramycin by microarray. Experiment Overall Design: We included 2 control (untreated) cultures and 2 tobramycin-treated cultures. We used mid-exponential phase cultures of P. aeruginosa PA14. Replicate cultures were incubated in the presence or absence of 5 μg/mL tobramycin for 30 minutes at 37°C.
Project description:To see the effect of lethal contrations of tobramycin under aerobic conditions in PAO1::PA0779 . RNA was isolated from 3 biological repeats of PAO1::PA0779 grown to mid-log in cationic adjusted meuller hinton broth containing 15mM KNO3, and 3 biological repeats of PAO1::PA0779 to which 2 ug/ml tobramycin was added after cells reached mid-log.