Expression profile for BW25113 ΔmqsRA with deoxycholate stress
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ABSTRACT:
ORGANISM(S): Escherichia coli Escherichia coli BW25113
PROVIDER: GSE59441 | GEO | 2015/01/09
SECONDARY ACCESSION(S): PRJNA255323
REPOSITORIES: GEO
Similar Datasets
Project description:MqsR/MqsA is a well-characterized toxin/antitoxin system with several regulatory roles. Deletion of mqsRA reduced growth with deoxycholate stress. Here we performed a microarray to determine the expression profile with and without mqsRA under deoxycholate stress to determine transcriptional regulation. Escherichia coli K-12 BW25113 with and without mqsRA was exposed to deoxycholate stress.
2015-01-09 | E-GEOD-59441 | biostudies-arrayexpress
Project description:Persisters are a subpopulation of metabolically-dormant cells in biofilms that are resistant to antibiotics; hence, understanding persister cell formation is important for controlling bacterial infections. Previously we discerned that MqsR and MqsA of Escherichia coli are a toxin/antitoxin pair that influence persister cell production via their regulation of Hha, CspD, and HokA. Here, to gain more insights into the origin of persisters, we used protein engineering to increase the toxicity of toxin MqsR by reasoning it would be easier to understand the effect of this toxin if it were more toxic. We found that two mutations (K3N and N31Y) increase the toxicity four fold and increase persistence 73 fold compared to native MqsR by making the protein less labile. A whole transcriptome study revealed that the MqsR variant represses acid resistance genes (gadABCEWX and hdeABD), multidrug resistance genes (mdtEF), and osmotic resistance genes (osmEY). Corroborating these microarray results, deletion of rpoS as well as the genes that the master stress response regulator RpoS controls, gadB, gadX, mdtF, and osmY, increased persister formation dramatically to the extent that nearly the whole population became persistent. Therefore, the more toxic MqsR increases persistence by decreasing the ability of the cell to respond to antibiotic stress through its RpoS-based regulation of acid resistance, multidrug resistance, and osmotic resistance systems.
2012-04-03 | GSE31054 | GEO
Project description:Persisters are cells which evade stresses like antibiotics and which are characterized by reduced metabolism and a lack of genetic alterations required to achieve this state. We showed previously that MqsR and MqsA of Escherichia coli are a toxin-antitoxin pair that influence cell physiology (e.g., biofilm formation and motility) via RNase activity as well as through regulation of toxin CspD. Here, we show that deletion of the mqsRA locus decreases persister cell formation and, consistent with this result, overexpression of MqsR increases persister cell formation. Furthermore, toxins Hha, CspD, and HokA increase persister cell formation. In addition, by overproducing MqsR in a series of isogenic mutants, we show that Hha and CspD are necessary for persister cell formation via MqsR overexpression. Surprisingly, Hfq, a small RNA chaperone, decreases persistence. A whole-transcriptome study shows that Hfq induces transport-related genes (oppA, oppB, oppC, oppD, oppF, and dppA), outer membrane protein-related genes (ybfM and ybfN), toxins (hha), and proteases (clpX, clpP, and lon). Taken together, these results indicate that toxins CspD and Hha influence persister cell formation via MqsR and that Hfq plays an important role in the regulation of persister cell formation via regulation of transport or outer membrane proteins.
2009-11-08 | GSE18852 | GEO
Project description:Here evidence is presented that MqsR and B3021 are a novel toxin-antitoxin (TA) system related to biofilm development and quorum sensing. Using whole-transcriptome studies and nickel enrichment DNA binding microarrays coupled with cell survival studies in which MqsR was overexpressed in isogenic mutants, we identified seven genes involved in MqsR toxicity (clpX, clpP, yfjZ, cspD, relB, relE, and hokA). Quantitative real-time polymerase chain reaction (qRT-PCR) confirmed consistent induction of the seven genes by the overexpression of MqsR as well as induction of nutrient starvation related genes (cstA, rpoS, and dps). Taken together, our results indicate that MqsR toxicity is caused via CspD (a DNA replication inhibitor), other TA systems (RelE/RelB and YfjZ), HokA (a small membrane toxin peptide), and nutrient-starvation conditions induced via CstA, RpoS, and Dps. Additionally, in vivo binding results show antitoxin B3021 binds to the promoter regions of genes encoding essential proteins for stress, growth and normal physiology.
2009-11-27 | GSE14203 | GEO
Project description:Persisters are cells which evade stresses like antibiotics and which are characterized by reduced metabolism and a lack of genetic alterations required to achieve this state. We showed previously that MqsR and MqsA of Escherichia coli are a toxin-antitoxin pair that influence cell physiology (e.g., biofilm formation and motility) via RNase activity as well as through regulation of toxin CspD. Here, we show that deletion of the mqsRA locus decreases persister cell formation and, consistent with this result, overexpression of MqsR increases persister cell formation. Furthermore, toxins Hha, CspD, and HokA increase persister cell formation. In addition, by overproducing MqsR in a series of isogenic mutants, we show that Hha and CspD are necessary for persister cell formation via MqsR overexpression. Surprisingly, Hfq, a small RNA chaperone, decreases persistence. A whole-transcriptome study shows that Hfq induces transport-related genes (oppA, oppB, oppC, oppD, oppF, and dppA), outer membrane protein-related genes (ybfM and ybfN), toxins (hha), and proteases (clpX, clpP, and lon). Taken together, these results indicate that toxins CspD and Hha influence persister cell formation via MqsR and that Hfq plays an important role in the regulation of persister cell formation via regulation of transport or outer membrane proteins. Strains: E. coli BW25113 K-12 hfq deleted mutant vs. wild-type Medium: LB Culture: Planktonic cell grown OD=0.5, adjusted OD=1.0, and then exposed to 100 ug/mL ampicillin for 2 h.
2009-11-07 | E-GEOD-18852 | biostudies-arrayexpress
Project description:Here evidence is presented that MqsR and B3021 are a novel toxin-antitoxin (TA) system related to biofilm development and quorum sensing. Using whole-transcriptome studies and nickel enrichment DNA binding microarrays coupled with cell survival studies in which MqsR was overexpressed in isogenic mutants, we identified seven genes involved in MqsR toxicity (clpX, clpP, yfjZ, cspD, relB, relE, and hokA). Quantitative real-time polymerase chain reaction (qRT-PCR) confirmed consistent induction of the seven genes by the overexpression of MqsR as well as induction of nutrient starvation related genes (cstA, rpoS, and dps). Taken together, our results indicate that MqsR toxicity is caused via CspD (a DNA replication inhibitor), other TA systems (RelE/RelB and YfjZ), HokA (a small membrane toxin peptide), and nutrient-starvation conditions induced via CstA, RpoS, and Dps. Additionally, in vivo binding results show antitoxin B3021 binds to the promoter regions of genes encoding essential proteins for stress, growth and normal physiology. Experiment Overall Design: Strain: E. coli K-12 BW25113 wt and mqsR deleted mutant Experiment Overall Design: Medium: LB medium Experiment Overall Design: Temperature: 37 oC Experiment Overall Design: Time: 24 h Experiment Overall Design: Cell type: Biofilm grown on glass wool and planktonic culture
2009-12-05 | E-GEOD-14203 | biostudies-arrayexpress
Project description:Persisters are a subpopulation of metabolically-dormant cells in biofilms that are resistant to antibiotics; hence, understanding persister cell formation is important for controlling bacterial infections. Previously we discerned that MqsR and MqsA of Escherichia coli are a toxin/antitoxin pair that influence persister cell production via their regulation of Hha, CspD, and HokA. Here, to gain more insights into the origin of persisters, we used protein engineering to increase the toxicity of toxin MqsR by reasoning it would be easier to understand the effect of this toxin if it were more toxic. We found that two mutations (K3N and N31Y) increase the toxicity four fold and increase persistence 73 fold compared to native MqsR by making the protein less labile. A whole transcriptome study revealed that the MqsR variant represses acid resistance genes (gadABCEWX and hdeABD), multidrug resistance genes (mdtEF), and osmotic resistance genes (osmEY). Corroborating these microarray results, deletion of rpoS as well as the genes that the master stress response regulator RpoS controls, gadB, gadX, mdtF, and osmY, increased persister formation dramatically to the extent that nearly the whole population became persistent. Therefore, the more toxic MqsR increases persistence by decreasing the ability of the cell to respond to antibiotic stress through its RpoS-based regulation of acid resistance, multidrug resistance, and osmotic resistance systems. For the whole-transcriptome study of BW25113 mqsR/pBS(Kan)-mqsR 2-1 versus BW25113 mqsR/pBS(Kan)-mqsR, planktonic cells were grown to a turbidity of 0.5 at 600 nm in LB medium with 1 mM IPTG at 37 M-BM-0C, adjusted the turbidity to 1, and exposed to 20 M-NM-<g/mL ampicillin with 1 mM IPTG for 1 h. Cells were isolated by centrifuging at 0M-BM-0C, and RNALaterM-BM-. buffer (Ambion, Cat# AM7021) was added to stabilize RNA during the RNA preparation steps. Total RNA was isolated from cell pellets with Qiagen RNeasy mini Kit (Cat# 74104) using a bead beater. cDNA was synthesized and fragmented to obtain 50-200 base cDNA fragments. The fragmented cDNA was labelled with Biotin-ddUTP, and hybridization was performed at 45M-BM-0C with 60 rpm for 16 hours. The probe array was washed, stained using Affymetrix Genechip Fluidics Station 450 and the software GenomeChipOperating Software (GCOS)M-bM-^@M-^], and scanned using Affymetrix Genechip scanner GCS3000 7G system and the software GenomeChipOperating Software (GCOS). Data were processed with MAS 5.0 Expression Analysis Default Setting. Genes were identified as differentially expressed if the expression ratio was higher than the standard deviation: 4.0 fold (enriched and differentially degraded) cutoff for the DNA microarrays (standard deviation 1.3 fold), and if the p-value for comparing two chips was less than 0.05.
2012-04-02 | E-GEOD-31054 | biostudies-arrayexpress
Project description:Bacterial toxin-antitoxin systems are thought to help bacteria to reduce their metabolism in various stressful conditions. Many toxins of the bacterial toxin-antitoxin systems are ribonucleases. Such toxins have been mostly viewed as degraders of mRNA, however recently it was demonstrated that they are also capable of cleaving non-coding RNA. MazF toxin is also hypothesized to reprogram E. colis translational machinery. Current cDNA libraries are part of a project which aims to identify the major RNA cleavage sites (in mRNA, rRNA and regulatory non-coding RNA) of MazF and MqsR toxins in E. coli. We wanted to elaborate on the roles of MazF and MqsR in E. coli: is MazF really involved in reprogramming the translational machinery or is MazF, along with MqsR, just a robust cleaver of RNA? We extracted total RNA from cultures where the expression of MazF or MqsR was induced for 2h and from cultures that had been recovering from toxin production for 30 minutes; RNA from log phase culture was used as the control. We used strand specific random primed paired end RNA sequencing data to locate the major cleavage sites. To map the cleavage sites, we counted 5’ end stacks of forward reads in each genomic position and compared them with total coverage. MazF and MqsR cleave at specific recognition sequences, ˇACA and GˇC respectively, which allowed us to eliminate the false positives. One of our initial aims was also to look for irregular RNA ligation events following toxin expression, thus we used long, 300 base reads in sequencing.
2018-10-11 | E-MTAB-6993 | biostudies-arrayexpress
Project description:The previously uncharacterized proteins HigB (unannotated) and HigA (PA4674) of Pseudomonas aeruginosa PA14 were found to form a type II TA system in which antitoxin HigA masks the RNase activity of toxin HigB through direct binding. To determine the physiological role of HigB/HigA in P. aeruginosa, a whole-transcriptome experiment was performed for the higA antitoxin deletion mutant of the PA14 strain compared to the wild-type PA14 strain. The rationale was that for the strain that lacks the antitoxin, the effect of the toxin could be discerned due to enhanced activity of the toxin. Furthermore, toxin HigB reduces production of the virulence factors pyochelin, pyocyanin, swarming, and biofilm formation.
2016-11-04 | GSE74730 | GEO
Project description:Toxin-antitoxin (TA) systems are ubiquitous throughout bacterial and archaeal genomes. TA systems consist of a stable toxin that inhibits growth and a labile antitoxin that prevents toxicity of the toxin. Here we made an artificial TA system (arT/arA) and performed a DNA microarray study for overproduction of the toxin.
2014-05-13 | GSE54271 | GEO