Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1074546 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Mycobacterium abscessus (Mab) causes serious infections that often require over 18 months of antibiotic combination therapy. With β lactam antibiotics being safe, double β-lactam and β-lactam/β-lactamase inhibitor combinations are of interest for improving treatment of Mab infections and minimizing toxicity. However, a mechanistic approach for building these combinations is lacking since little is known about which penicillin-binding protein (PBP) target receptors are inactivated by different β-lactams in Mab. This project aimed to identify PBPs in Mab and study the binding affinities of each of these PBPs with β-lactam antibiotics. These first PBP occupancy patterns in Mab provide a mechanistic foundation for selecting and optimizing safe and effective combination therapies with β-lactams.
2020-11-24 | PXD022644 | Pride
Project description:Emergence of resistance to novel β-lactam β-lactamase inhibitor combinations due to horizontally-acquired AmpC (FOX-4) in Pseudomonas aeruginosa
| PRJEB34942 | ENA
Project description:In vitro efficacy of new β-lactam – β-lactamase inhibitor combinations for Mycobacterium tuberculosis
| PRJEB53318 | ENA
Project description:The transcriptional regulator AmpR controls expression of the AmpC ß-lactamase in P. aeruginosa and other bacteria. Studies have demonstrated that in addition to regulating ampC expression, AmpR also regulates the expression of the sigma factor AlgT/U and the production of some quorum-sensing regulated virulence factors. In order to understand the ampR regulon, we compared the expression profiles of PAO1 and its isogenic ampR mutant, PAO∆ampR in the presence and absence of sub-MIC ß-lactam stress. The analysis demonstrates that the ampR regulon is much more extensive than previously thought, with the deletion of ampR affecting the expression of over 300 genes. Expression of an additional 207 genes are affected by AmpR when the cells are exposed to sub-MIC ß-lactam stress, indicating that the ampR regulon in P. aeruginosa is much more extensive than previously thought. An inframe deletion of ampR was generated in P. aeruginosa PAO1. The wild type and ampR mutant strains were grown to mid-log phase and subjected to sub-MIC ß-lactam exposure. Total RNA was isolated from 2-hour ß-lactam exposed and unexposed cells to monitor changes in gene expression arising due to loss of ampR in the presence and absence of ß-lactam exposure.
2012-03-29 | E-GEOD-33188 | biostudies-arrayexpress
Project description:Emergence of resistance to novel cephalosporin-β-lactamase inhibitor combinations through the modification of the Pseudomonas aeruginosa MexCD-OprJ efflux pump
| PRJEB44132 | ENA
Project description:Pseudomonas aeruginosa is a predominant pathogen in chronic lung infections in individuals with cystic fibrosis (CF). Epidemic strains of P. aeruginosa, such as the Liverpool Epidemic Strain (LES), are capable of transferring between CF patients and have been associated with increased hospital visits and antibiotic treatments. We used label-free quantitative proteomics to compare the laboratory strain PAO1, beta-lactam resistant isolate LESB58, and beta-lactam susceptible isolate LESlike1 and their responses to three beta-lactams (aztreonam, carbenicillin, piperacillin), the aminoglycoside tobramycin, and hydrogen peroxide. Across all samples, we identified 3019 proteins with a minimum of two peptides. We found that LESB58 showed a large response to treatment with the beta-lactam carbenicillin, with 644 proteins significantly increased in abundance and 590 proteins significantly decreased in abundance (Students t-test, p≤0.05, FDR=0.05, S0=1). Proteomic characterization of an additional beta-lactam resistant isolate, LES431, exposed to carbenicillin showed that this response was shared by both isolates. Part of the response to carbenicillin in LESB58 included an increase in abundance in proteins involved in cell wall synthesis and division.
2023-08-23 | PXD034831 | Pride
Project description:The surge of antimicrobial resistance in recent decades threatens efficacy of current antibiotics, particularly against Pseudomonas aeruginosa, a highly resistant gram-negative pathogen. The asymmetric outer membrane of P. aeruginosa combined with its array of efflux pumps provide a barrier to xenobiotic intracellular accumulation, thus making the discovery of novel drugs with whole cell antibacterial activity very challenging. We adapted PROSPECT, a genome-wide, target-based, whole cell screening strategy, to take a focused approach to discover small molecule probes with specific activity against engineered P. aeruginosa mutants depleted for essential proteins localized at the outer membrane. We identified BRD1401, a small molecule that has specific activity against a P. aeruginosa mutant depleted for the essential lipoprotein, OprL. Genetic studies identified a novel link between OprL and the non-essential, outer membrane β barrel protein, OprH, to modulate BRD1401 activity. BRD1401 directly bound to OprH to disrupt the known interaction between OprH and lipopolysaccharide (LPS) in vitro and in whole bacteria. OprH also biochemically interacted with OprL, thus providing a link between outer membrane and peptidoglycan in P. aeruginosa. Thus, a whole cell, multiplexed screen against P. aeruginosa identified a species-specific inhibitor and probe molecule that revealed novel pathogen biology.
2024-03-15 | GSE252756 | GEO
Project description:The surge of antimicrobial resistance in recent decades threatens efficacy of current antibiotics, particularly against Pseudomonas aeruginosa, a highly resistant gram-negative pathogen. The asymmetric outer membrane of P. aeruginosa combined with its array of efflux pumps provide a barrier to xenobiotic intracellular accumulation, thus making the discovery of novel drugs with whole cell antibacterial activity very challenging. We adapted PROSPECT, a genome-wide, target-based, whole cell screening strategy, to take a focused approach to discover small molecule probes with specific activity against engineered P. aeruginosa mutants depleted for essential proteins localized at the outer membrane. We identified BRD1401, a small molecule that has specific activity against a P. aeruginosa mutant depleted for the essential lipoprotein, OprL. Genetic studies identified a novel link between OprL and the non-essential, outer membrane β barrel protein, OprH, to modulate BRD1401 activity. BRD1401 directly bound to OprH to disrupt the known interaction between OprH and lipopolysaccharide (LPS) in vitro and in whole bacteria. OprH also biochemically interacted with OprL, thus providing a link between outer membrane and peptidoglycan in P. aeruginosa. Thus, a whole cell, multiplexed screen against P. aeruginosa identified a species-specific inhibitor and probe molecule that revealed novel pathogen biology.
2024-03-15 | GSE254108 | GEO
Project description:The transcriptional regulator AmpR controls expression of the AmpC ß-lactamase in P. aeruginosa and other bacteria. Studies have demonstrated that in addition to regulating ampC expression, AmpR also regulates the expression of the sigma factor AlgT/U and the production of some quorum-sensing regulated virulence factors. In order to understand the ampR regulon, we compared the expression profiles of PAO1 and its isogenic ampR mutant, PAO∆ampR in the presence and absence of sub-MIC ß-lactam stress. The analysis demonstrates that the ampR regulon is much more extensive than previously thought, with the deletion of ampR affecting the expression of over 300 genes. Expression of an additional 207 genes are affected by AmpR when the cells are exposed to sub-MIC ß-lactam stress, indicating that the ampR regulon in P. aeruginosa is much more extensive than previously thought.
2012-03-30 | GSE33188 | GEO
Project description:We performed RNA-seq experiments to compare the gene expression profiles of cells expressing TEM-1 beta-lactamase with single-codon substitutions in the absence of beta-lactam antibiotics. Mutations with deleterious fitness effects in the absense of antibiotics also caused significant changes in gene expression, primarily in the induction of specific outer envelope stress response pathways and, in some cases, the mild-induction of a few genes in the heat-shock response pathway.
2019-10-28 | GSE137362 | GEO