Similar Datasets
Project description:Biofilm formation by Pseudomonas aeruginosa relies on specific changes in gene expression. Some of these genes, for instance, control antibiotic resistance. We used microarrays to detail the global programme of gene expression underlying biofilm formation and identified distinct classes of up-regulated genes during this process. Pseudomonas aeruginosa PAO1 cells were grown as planktonic cells in LB broth for 4 hours (PC4) or 24 hours (PC24) and sessile cels for 24 hours.
2011-06-17 | E-GEOD-30021 | biostudies-arrayexpress
Project description:Biofilm formation by Pseudomonas aeruginosa relies on specific changes in gene expression. Some of these genes, for instance, control antibiotic resistance. We used microarrays to detail the global programme of gene expression underlying biofilm formation and identified distinct classes of up-regulated genes during this process.
2011-06-17 | GSE30021 | GEO
Project description:Biofilm formation and type III secretion have been shown to be reciprocally regulated in P. aeruginosa, and it has been suggested that factors related to acute infection may be incompatible with biofilm formation. We investigated how growth conditions influence the production of virulence factors by studying the inter-relationships between colonies, biofilms and planktonic cells. We found that biofilms in our growth conditions express the type III secretion and these lifestyles are therefore not mutually exclusive in P. aeruginosa. Keywords: Comparison of different growth modes and growth phases of Pseudomonas aeruginosa
2008-11-01 | GSE12207 | GEO
Project description:A hallmark of the biofilm architecture is the presence of microcolonies. However, little is known about the underlying mechanisms governing microcolony formation. In the human pathogen Pseudomonas aeruginosa, microcolony formation is dependent on the two-component regulator MifR, with mifR mutant biofilms exhibiting an overall thin structure lacking microcolonies, and overexpression of mifR resulting in hyper-microcolony formation. Here, we made use of the distinct MifR-dependent phenotypes to elucidate mechanisms associated with microcolony formation. Using global transcriptomic and proteomic approaches, we demonstrate that cells located within microcolonies experience stressful, oxygen limited, and energy starving conditions, as indicated by the activation of stress response mechanisms and anaerobic and fermentative processes, in particular pyruvate fermentation. Inactivation of genes involved in pyruvate utilization including uspK, acnA and ldhA abrogated microcolony formation in a manner similar to mifR inactivation. Moreover, depletion of pyruvate from the growth medium impaired biofilm and microcolony formation, while addition of pyruvate significantly increased microcolony formation. Addition of pyruvate partly restored microcolony formation in M-bM-^HM-^FmifR biofilms. Moreover, addition of pyruvate to or expression of mifR in lactate dehydrogenase (ldhA) mutant biofilms did not restore microcolony formation. Consistent with the finding of denitrification genes not demonstrating distinct expression patterns in biofilms forming or lacking microcolonies, addition of nitrate did not alter microcolony formation. Our findings indicate the fermentative utilization of pyruvate to be a microcolony-specific adaptation to the oxygen limitation and energy starvation of the P. aeruginosa biofilm environment. For biofilm growth experiments, three independent replicates of P. aeruginosa strains PAO1 and M-NM-^TmifR were grown as biofilms in a flow-through system using a once-through continuous flow tube reactor system for biofilm sample collection and in flow cells (BioSurface Technologies) for the analysis of biofilm architecture as previously described (Sauer et al., 2002, Sauer et al., 2004, Petrova & Sauer, 2009). Cells were treated with RNAprotect (Qiagen) and total RNA was extracted using an RNeasy mini purification kit (Qiagen) per the manufacturerM-bM-^@M-^Ys instructions. RNA quality and the presence of residual DNA were checked on an Agilent Bioanalyzer 2100 electrophoretic system pre- and post-DNase treatment. Ten micrograms of total RNA was used for cDNA synthesis, fragmentation, and labeling according to the Affymetrix GeneChip P. aeruginosa genome array expression analysis protocol. Sauer, K., A. K. Camper, G. D. Ehrlich, J. W. Costerton & D. G. Davies, (2002) Pseudomonas aeruginosa displays multiple phenotypes during development as a biofilm. J. Bacteriol. 184: 1140-1154. Sauer, K., M. C. Cullen, A. H. Rickard, L. A. H. Zeef, D. G. Davies & P. Gilbert, (2004) Characterization of nutrient-induced dispersion in Pseudomonas aeruginosa PAO1 biofilm. J. Bacteriol. 186: 7312-7326. Petrova, O. E. & K. Sauer, (2009) A novel signaling network essential for regulating Pseudomonas aeruginosa biofilm development. PLoS Pathogens 5: e1000668.
2012-04-30 | E-GEOD-35286 | biostudies-arrayexpress
Project description:Biofilms are ubiquitous in natural, medical, and engineering environments. While most antibiotics that primarily aim to inhibit cell growth may result in bacterial drug resistance, biofilm inhibitors do not affect cell growth and there is less chance of developing resistance. This work sought to identify novel, non-toxic and potent biofilm inhibitors from Streptomyces bacteria for reducing the biofilm formation of Pseudomonas aeruginosa PAO1. Out of 4300 Streptomyces strains, one species produced and secreted peptide(s) to inhibit P. aeruginosa biofilm formation by 93% without affecting the growth of planktonic cells. Global transcriptome analyses (DNA microarray) revealed that the supernatant of the Streptomyces 230 strain induced phenazine, pyoverdine, and pyochelin synthesis genes. Electron microscopy showed that the supernatant of Streptomyces 230 strain reduced the production of polymeric matrix in P. aeruginosa biofilm cells, while the Streptomyces species enhanced swarming motility of P. aeruginosa. Therefore, current study suggests that Streptomyces bacteria are an important resource of biofilm inhibitors as well as antibiotics.
2013-03-21 | GSE28194 | GEO
Project description:Microarray analysis for the biofilm cells of Pseudomonas aeruginosa PA14 wild-type vs the tpbA (PA14_13660) mutant in LB medium at 4 and 7 h at 37C Microarray analysis for the biofilm cells of Pseudomonas aeruginosa PA14 wild-type vs the tpbA (PA14_13660) mutant in LB medium at 4 and 7 h at 37C.
2009-05-23 | E-GEOD-13871 | biostudies-arrayexpress
Project description:Pseudomonas aeruginosa is known to tolerate antibiotic therapy during infection. This prevents clearance of infection and negatively impacts patient outcomes. Here, we report the transcriptome sequence of antibiotic-treated and untreated P. aeruginosa cultures and the differential gene expression observed when treated cells are compared to untreated cells.
2018-10-31 | GSE120602 | GEO
Project description:Microarray analysis for the biofilm cells of Pseudomonas aeruginosa PA14 wild-type vs the tpbA (PA14_13660) mutant in LB medium at 4 and 7 h at 37C
2009-05-23 | GSE13871 | GEO
Project description:ClpV3 is a cytoplasmic AAA+ ATPase protein and is an essential component of H3-T6SS in Pseudomonas aeruginosa. Here, we report that an H3-T6SS deletion mutant PAO1(ΔclpV3) significantly affected the virulence-related phenotypes including pyocyanin production, biofilm formation, proteolytic activity and motilities. Most interestingly, the expression of T3SS genes was markedly affected, indicating a strong link between H3-T6SS and T3SS. RNA-Sequencing was performed to globally identify the genes differentially expressed when H3-T6SS was inactivated and the results obtained could be well correlated to the observed phenotypes.
2020-04-20 | GSE148116 | GEO
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.
2014-01-01 | GSE51076 | GEO