Ontology highlight
ABSTRACT:
PROVIDER: PRJNA666010 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:In our study, we obtained evidence showing that, in the presence of tetracycline, AcrAB-TolC multidrug efflux pump was required for production of protein encoded by a conjugative plasmid acquired by bacterial conjugation. We then address the role of AcrAB-TolC multidrug efflux pump on the level of protein synthesis activity in the presence of tetracycline, which inhibits protein translation by targeting ribosomal 16S rRNA and competing with binding of the anticodon-stem loop of an A-site tRNA. We used a quantitative TMT-nanoLC-mass spectrometry approach to obtained the protein relative abundance ratio before and after incubation with tetracycline, and so in wild-type(MG1655, K12) and AcrAB-TolC mutant strains (ΔacrA, ΔacrB and ΔtolC).
2019-07-16 | PXD011286 | Pride
Project description:Expression of efflux pumps is a key feature of most cells which are resistant to multiple antibiotics. This study used TraDIS-Xpress, a genome wide transposon mutagenesis technology to identify genes in Escherichia coli and Salmonella Typhimurium involved in drug efflux and its regulation. We exposed mutant libraries to the canonical efflux substrate acriflavine in the presence and absence of the efflux inhibitor phenylalanine-arginine β-naphthylamide. Comparisons between conditions identified efflux specific and drug specific responses. Known efflux associated genes were easily identified including: AcrAB-TolC, MarA, RamA and SoxS confirming specificity of the response. Further genes encoding cell envelope maintenance enzymes and products involved with stringent response activation, DNA housekeeping, respiration and glutathione biosynthesis were also identified as affecting efflux activity in both species. We identified a conserved set of pathways crucial for efflux activity in these experimental conditions which expands the list of genes known to impact efflux efficacy.
2022-11-12 | E-MTAB-12353 | biostudies-arrayexpress
Project description:Efflux pumps of the resistance-nodulation-division (RND) superfamily, particularly the AcrAB-TolC and MexAB-OprM, besides mediating intrinsic and acquired resistance, also intervene in bacterial pathogenicity. Inhibitors of such pumps could restore activities of antibiotics and curb bacterial virulence. Here, we identify pyrrole-based compounds that boost antibiotic activity in Escherichia coli and Pseudomonas aeruginosa by inhibiting their archetype RND transporters. The discovered efflux pump inhibitors (EPIs) inhibit the efflux of fluorescent probes, attenuate persister formation, and diminish resistant mutant development. Molecular docking and biophysical studies revealed that the EPIs bind to AcrB. EPIs also possess an anti-pathogenic potential and attenuate P. aeruginosa virulence in vivo. The excellent efficacy of the EPI-antibiotic combination was evidenced in animal lung infection and sepsis protection models. These findings indicate that EPIs discovered herein with no off-target effects and negligible toxicity are potential antibiotic adjuvants to address life-threatening bacterial infections.
2024-03-18 | GSE210309 | GEO
Project description:Membrane efflux pumps play a major role in bacterial multidrug resistance. The tripartite multidrug efflux pump system from Escherichia coli, AcrAB-TolC, is a target for inhibition to lessen resistance development and restore antibiotic efficacy, with homologs in other ESKAPE pathogens. Here, we rationalize a mechanism of inhibition against the periplasmic adaptor protein, AcrA, using a combination of hydrogen/deuterium exchange mass spectrometry, cellular efflux assays, and molecular dynamics simulations. We define the structural dynamics of AcrA and find that an inhibitor can inflict long-range stabilisation across all four of its domains, whereas an interacting efflux substrate has minimal effect. Our results support a model where an inhibitor forms a molecular wedge within a cleft between the lipoyl and αβ domains of AcrA, diminishing its conformational transmission of drug-evoked signals from AcrB to TolC. This work provides molecular insights into multidrug adaptor protein function which could be valuable for developing antimicrobial therapeutics.
2023-06-01 | PXD041359 | Pride
Project description:Tripartite resistance nodulation and cell division multidrug efflux pumps span the periplasm and are major drivers of multidrug resistance among Gram-negative bacteria. Cations, such as Mg2+, become concentrated within the periplasm and, in contrast to the cytoplasm, it’s pH is sensitive to conditions outside the cell. Here, we reveal an interplay between Mg2+ and pH in modulating the structural dynamics of the periplasmic adaptor protein, AcrA, and its function within the prototypical AcrAB-TolC multidrug pump from Escherichia coli. In the absence of Mg2+, AcrA becomes increasingly plastic within acidic conditions, but when Mg2+ is bound this is ameliorated, resulting instead in domain specific organisation. We establish a unique histidine residue directs these dynamics and is essential for sustaining pump activity across acidic, neutral, and basic regimes. Overall, we propose Mg2+ conserves AcrA structural mobility to ensure optimal AcrAB-TolC function within rapid changing environments commonly faced during bacterial infection and colonization.
2024-12-30 | PXD057200 | Pride
Project description:Efflux pumps are a significant challenge for the development of new antibacterial agents. Overcoming efflux requires an in-depth understanding of efflux pump functions, substrate specificities, and the development of inhibitors. However, the complexities of drug efflux networks have limited such studies. To address these challenges, we report the generation of Efflux KnockOut-35 (EKO-35), a highly susceptible Escherichia coli strain lacking 35 efflux pumps. We demonstrate the utility of this strain by constructing an efflux platform consisting of strains individually expressing genes encoding efflux pumps forming tripartite complexes with the outer membrane channel TolC. This platform was profiled against a curated diverse compound collection, which enabled us to define physicochemical properties that contribute to transport. We also show the E. coli drug efflux network is conditionally essential for growth, and that the platform can be used to investigate efflux pump inhibitor specificities and also efflux pump interplay. We believe EKO-35 and the efflux platform will have widespread application for the study of drug efflux.
2022-08-31 | PXD033975 | Pride
Project description:AcrR is a known transcriptional repressor for AcrAB-TolC multidrug efflux system and mar-sox regulators. We used microarrays to investigate genome-wide target genes for AcrR. In the acrR deletion mutant, the transcription of genes for flagella and motility are significantly increased, indicating that AcrR plays a role in motility of E. coli.
2016-07-27 | GSE84847 | GEO
Project description:AcrR is a known transcriptional repressor for AcrAB-TolC multidrug efflux system and mar-sox regulators. We used microarrays to investigate genome-wide target genes for AcrR. In the acrR deletion mutant, the transcription of genes for flagella and motility are significantly increased, indicating that AcrR plays a role in motility of E. coli. Two E. coli strains, acrR deletion mutant and wild-type, grew on LB medium. At exponential phase (OD600=0.8), RNA was extracted and hybridized on Affymetrix microarrays. We sought to find the genes that the transcription is significantly increased in the acrR deletion mutant.
2016-07-27 | E-GEOD-84847 | biostudies-arrayexpress
Project description:The acquisition of multi-drug resistance (MDR) determinants jeopardizes treatment of bacterial infections with antibiotics. The tripartite efflux pump AcrAB-NodT confers adaptive MDR in the non-pathogenic α-proteobacterium Caulobacter crescentus via transcriptional induction by first-generation quinolone antibiotics. We discovered that overexpression of AcrAB-NodT by mutation or exogenous inducers confers resistance to cephalosporin and penicillin (β-lactam) antibiotics. Combining two-step mutagenesis-sequencing (Mut-Seq) and cephalosporin-resistant point mutants, we dissected how TipR targets a common operator of divergent tipR and acrAB-nodT promoter in adaptive and/or potentiated AcrAB-NodT-directed efflux. Chemical screening identified compounds that either interfere with DNA-binding by TipR or induce its ClpXP-dependent proteolytic turnover. We found that long-term induction of AcrAB-NodT disfigures the envelope and that homeostatic control by TipR includes co-induction of the DnaJ-like co-chaperone DjlA, to boost pump assembly and/or capacity in anticipation of envelope stress. Thus, the adaptive MDR regulatory circuitry reconciles drug efflux with co-chaperone function for trans-envelope assemblies and maintenance.
2023-11-09 | GSE225487 | GEO
Project description:The acquisition of multi-drug resistance (MDR) determinants jeopardizes treatment of bacterial infections with antibiotics. The tripartite efflux pump AcrAB-NodT confers adaptive MDR in the non-pathogenic α-proteobacterium Caulobacter crescentus via transcriptional induction by first-generation quinolone antibiotics. We discovered that overexpression of AcrAB-NodT by mutation or exogenous inducers confers resistance to cephalosporin and penicillin (β-lactam) antibiotics. Combining two-step mutagenesis-sequencing (Mut-Seq) and cephalosporin-resistant point mutants, we dissected how TipR targets a common operator of divergent tipR and acrAB-nodT promoter in adaptive and/or potentiated AcrAB-NodT-directed efflux. Chemical screening identified compounds that either interfere with DNA-binding by TipR or induce its ClpXP-dependent proteolytic turnover. We found that long-term induction of AcrAB-NodT disfigures the envelope and that homeostatic control by TipR includes co-induction of the DnaJ-like co-chaperone DjlA, to boost pump assembly and/or capacity in anticipation of envelope stress. Thus, the adaptive MDR regulatory circuitry reconciles drug efflux with co-chaperone function for trans-envelope assemblies and maintenance.
2023-11-09 | GSE238117 | GEO