Expression data from a paraquat time course experiment in wild type and SoxR deficient strains
Ontology highlight
ABSTRACT:
ORGANISM(S): Escherichia coli
PROVIDER: GSE6992 | GEO | 2007/02/10
SECONDARY ACCESSION(S): PRJNA99267
REPOSITORIES: GEO
Similar Datasets
Project description:SoxR and SoxS constitute an intracellular signal response system that rapidly detects changes in superoxide levels and modulates gene expression in E. coli. A time series microarray design was used to identify co-regulated SoxRS dependent and independent genes affected by superoxide Experiment Overall Design: To determine the immediate transcriptional response of E. coli to superoxide, we conducted a time series assay of mRNA levels immediately following the addition of paraquat. The wild type strain MG1655 and a strain with a precise deletion in soxR was grown in EZ Rich Defined Medium, a modification of Neidhardtâs defined rich medium. When cultures reached an OD600=0.5, 250µM paraquat (PQ) was added, a concentration that triggers the SoxRS transcriptional cascade, but only has a small effect on exponential growth rate in rich media. Samples were taken immediately before exposure to PQ, and every 2 minutes after exposure, for 10 minutes.
2008-06-15 | E-GEOD-6992 | biostudies-arrayexpress
Project description:Oxidative stress that originates from reactive oxygen species (ROS) is an inevitable consequence of aerobic respiration in bacteria. Three transcription factors (TFs), OxyR, SoxR, and SoxS play a critical role in transcriptional regulation of the defense system. However, the full genome-wide regulatory potential of them remains elusive. Here, we comprehensively reconstruct genome-wide OxyR, SoxR, and SoxS transcriptional regulatory networks in Escherichia coli under oxidative stress. Integrative data analysis reveals that OxyR, SoxR, and SoxS regulons are comprised of 38 genes in 28 transcription units (TUs), 11 genes in 10 TUs, and 34 genes in 25 TUs, respectively, significantly expanding the current knowledge of their regulatory networks. Comparison of them to other stress-response regulatory networks highlights minimal overlap between their regulons, indicating that E. coli has a series of relatively distinct stress responses covering the range of different stresses. We also demonstrate that these intricate networks coordinate detoxification process with DNA and protein damage repair, cell wall synthesis, divalent metal ion homeostasis, as well as metabolic robustness to produce overall response of E. coli to oxidative stress.
2015-08-13 | GSE65711 | GEO
Project description:Oxidative stress that originates from reactive oxygen species (ROS) is an inevitable consequence of aerobic respiration in bacteria. Three transcription factors (TFs), OxyR, SoxR, and SoxS play a critical role in transcriptional regulation of the defense system. However, the full genome-wide regulatory potential of them remains elusive. Here, we comprehensively reconstruct genome-wide OxyR, SoxR, and SoxS transcriptional regulatory networks in Escherichia coli under oxidative stress. Integrative data analysis reveals that OxyR, SoxR, and SoxS regulons are comprised of 38 genes in 28 transcription units (TUs), 11 genes in 10 TUs, and 34 genes in 25 TUs, respectively, significantly expanding the current knowledge of their regulatory networks. Comparison of them to other stress-response regulatory networks highlights minimal overlap between their regulons, indicating that E. coli has a series of relatively distinct stress responses covering the range of different stresses. We also demonstrate that these intricate networks coordinate detoxification process with DNA and protein damage repair, cell wall synthesis, divalent metal ion homeostasis, as well as metabolic robustness to produce overall response of E. coli to oxidative stress.
2015-08-13 | GSE65710 | GEO
Project description:Oxidative stress that originates from reactive oxygen species (ROS) is an inevitable consequence of aerobic respiration in bacteria. Three transcription factors (TFs), OxyR, SoxR, and SoxS play a critical role in transcriptional regulation of the defense system. However, the full genome-wide regulatory potential of them remains elusive. Here, we comprehensively reconstruct genome-wide OxyR, SoxR, and SoxS transcriptional regulatory networks in Escherichia coli under oxidative stress. Integrative data analysis reveals that OxyR, SoxR, and SoxS regulons are comprised of 38 genes in 28 transcription units (TUs), 11 genes in 10 TUs, and 34 genes in 25 TUs, respectively, significantly expanding the current knowledge of their regulatory networks. Comparison of them to other stress-response regulatory networks highlights minimal overlap between their regulons, indicating that E. coli has a series of relatively distinct stress responses covering the range of different stresses. We also demonstrate that these intricate networks coordinate detoxification process with DNA and protein damage repair, cell wall synthesis, divalent metal ion homeostasis, as well as metabolic robustness to produce overall response of E. coli to oxidative stress. A total of six samples were analyzed. oxyR-8myc, soxR-8myc, and soxS-8myc tagged cells were cultured in M9 minimal media with 0.2% glucose. Then cells were treated with 250 uM of paraquat at mid-log pahse for 20 min with agitation.
2015-08-13 | E-GEOD-65710 | biostudies-arrayexpress
Project description:Oxidative stress that originates from reactive oxygen species (ROS) is an inevitable consequence of aerobic respiration in bacteria. Three transcription factors (TFs), OxyR, SoxR, and SoxS play a critical role in transcriptional regulation of the defense system. However, the full genome-wide regulatory potential of them remains elusive. Here, we comprehensively reconstruct genome-wide OxyR, SoxR, and SoxS transcriptional regulatory networks in Escherichia coli under oxidative stress. Integrative data analysis reveals that OxyR, SoxR, and SoxS regulons are comprised of 38 genes in 28 transcription units (TUs), 11 genes in 10 TUs, and 34 genes in 25 TUs, respectively, significantly expanding the current knowledge of their regulatory networks. Comparison of them to other stress-response regulatory networks highlights minimal overlap between their regulons, indicating that E. coli has a series of relatively distinct stress responses covering the range of different stresses. We also demonstrate that these intricate networks coordinate detoxification process with DNA and protein damage repair, cell wall synthesis, divalent metal ion homeostasis, as well as metabolic robustness to produce overall response of E. coli to oxidative stress. A total of eight samples were analyzed. WT, ΔoxyR, ΔsoxR, and ΔsoxS mutant cells were cultured in M9 minimal media with 0.2% glucose. Then cells were treated with 250 uM of paraquat at mid-log pahse for 20 min with agitation.
2015-08-13 | E-GEOD-65711 | biostudies-arrayexpress
Project description:In bacteria the defence system to counter oxidative stress is orchestrated by three transcriptional factors – SoxS, SoxR and OxyR. Although the transcriptional regulon of these factors are known in many bacteria, similar data is not available for K. pneumoniae. To address this data gap, oxidative stress was induced in K. pneumoniae MGH 78578 using paraquat and the corresponding regulon was identified using RNA-seq. Since soxS was significantly induced , a soxS mutant was constructed to decipher this regulon in K. pneumoniae MGH75878. The ‘oxidative SoxS regulon’, comprising common genes differentially regulated genes in oxidative and soxS regulon was identified from both regulons – characterised a stringent group of genes which were regulated by SoxS during oxidative stress. Efflux pump encoding genes like acrAB-tolC, acrE along with marRABwere identified in the oxidative SoxS regulon. The phenotypic effect of the observed efflux pump regulation was confirmed in the soxS mutant that exhibited an 2 fold reduction in the minimum bactericidal concentration (MBC) against tetracycline compared to that of the isogenic wild type. Impaired efflux activity, allowing tetracycline to be accumulated in the cytoplasm to bactericidal levels, was further confirmed using tetraphenylphosphonium (TPP+) ion accumulation assay. The susceptibility of the soxS mutant against tetracycline was also apparent in vivo, in the zebrafish embryo model. We conclude that the soxS gene could be considered as a genetic target against which an inhibitor could be developed and be used in combinatorial therapy with tetracycline to combat infections associated with multi-drug resistant K. pneumoniae.
2021-05-26 | GSE146844 | GEO
Project description:We used microarrays to detail Arabidopsis gene expression in response to paraquat, a herbicide that acts as a terminal oxidant of photosystem I that in the light leads to the enhanced generation of superoxide and hydrogen peroxide inside plastids. Within a few hours after paraquat treatment changes in nuclear gene expression occur. Distinct sets of genes were activated that were different from those induced by another reactive oxygen species, singlet oxygen. Keywords: Time course
2008-02-11 | GSE10464 | GEO
Project description:Inflorescences of ag-1;35S::AG-GR plants were treated for 0,4,8,10, or 16 hours with dexamethasone or were mock-treated. Two biologically independent sets of samples were generated and RNA probes derived from these samples were co-hybridized to a cDNA array enriched for flower-specific transcripts. Keywords: time-course
2004-07-15 | GSE1424 | GEO
Project description:The declining health of coral reefs worldwide is likely to intensify in response to continued anthropogenic disturbance from coastal development, pollution, and climate change. In response to these stresses, reef-building corals may exhibit bleaching, which marks the breakdown in symbiosis between coral and zooxanthellae. Mass coral bleaching due to elevated water temperature can devastate coral reefs on a large geographic scale. In order to understand the molecular and cellular basis of bleaching in corals, we have measured gene expression changes associated with thermal stress and bleaching using a cDNA microarray containing 1,310 genes of the Caribbean coral Montastraea faveolata. In a first experiment, we identified differentially expressed genes by comparing experimentally bleached M. faveolata fragments to control non-heat-stressed fragments. We also identified differentially expressed genes during a time course experiment with four time points across nine days. Results suggest that thermal stress and bleaching in M. faveolata affect the following processes: oxidative stress, Ca2+ homeostasis, cytoskeletal organization, cell death, calcification, metabolism, protein synthesis, heat shock protein activity, and transposon activity. These results represent the first large-scale transcriptomic study focused on revealing the cellular foundation of thermal stress-induced coral bleaching. We postulate that oxidative stress in thermal-stressed corals causes a disruption of Ca2+ homeostasis, which in turn leads to cytoskeletal and cell adhesion changes, decreased calcification, and the initiation of cell death via apoptosis and necrosis. Keywords: thermal stress response, time course, coral bleaching
2008-05-31 | GSE10632 | GEO
Project description:We report 6 genes that were found to be regulated by SoxR in stationary phase when the bacteria produce the antibiotic actinorhodin. Five of these genes are previously confirmed SoxR targets; the sixth is a novel SoxR-target.
2014-08-04 | GSE57268 | GEO