Ontology highlight
ABSTRACT:
PROVIDER: PRJNA731849 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Acinetobacter baumannii is often highly resistant to multiple antimicrobials, posing a risk of treatment failure. Colistin is often chosen as a “last resort” for treatment of the bacterial infection, but resistance is easily developed when the bacteria is exposed to the drug. Thus a comprehensive analysis of colistin-mediated changes in colistin-susceptible and colistin-resistant A. baumannii is needed. In this study, we used a colistin-susceptible A. baumannii clinical isolate and a colistin-resistant isogenic mutant. Whole genome sequencing revealed that the resistant isolate harbored a PmrBL208F mutation conferring colistin resistance, and all other single nucleotide alterations were located in intergenic regions. Using scanning electron microscopy, we observed that the colistin-resistant mutant had a shorter cell length than the parental isolate, and filamented cells were observed when both isolates were exposed to inhibitory concentration of colistin. When the isolates were treated with inhibitory concentrations of colistin, more than 80% of the genes were upregulated, including genes associated with antioxidative stress response pathways. This results helped a better understanding for the morphological difference between the colistin-susceptible and –resistant isolates and differed colistin-mediated responses in A. baumannii isolates by their susceptibility to this drug.
2025-05-02 | GSE267612 | GEO
Project description:This study aims to determine the epidemiology of Enterobacteriaceae resistant to antibiotics of last resort in pregnant women in labour at a tertiary hospital, Pretoria, South Africa. Rectal swabs shall be used to screen for colonisation with CRE and colistin-resistant Enterobacteriales in pregnant women during labour. Carbapenem and colistin-resistant Enterobacterales can cause the following infections: bacteraemia; nosocomial pneumonia; urinary tract infections, and intra-abdominal infections. Due to limited treatment options, infections caused by these multidrug-resistant organisms are associated with a mortality rate of 40-50%. Screening for colonisation of carbapenem-resistant Enterobacteriaceae (CRE) and colistin-resistant Enterobacteriaceae will help implement infection and prevention measures to limit the spread of these multidrug-resistant organisms.
2022-07-20 | GSE208573 | GEO
Project description:The emergence of colistin resistance in carbapenem-resistant and extended-spectrum ß-lactamase (ESBL)-producing bacteria is a significant threat to human health, and new treatment strategies are urgently required. Here we investigated the ability of the safe-for-human use ionophore PBT2 to restore antibiotic sensitivity in several polymyxin-resistant, ESBL-producing, carbapenem resistant Gram-negative human pathogens. PBT2 was observed to resensitize Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa to last-resort polymyxin class antibiotics, including a ‘next generation’ polymyxin derivative, FADDI-287. To gain additional insight into the potential mechanism of action of PBT2, we analyzed the transcriptome of K. pneumoniae and E. coli in the presence of sub-inhibitory concentrations of PBT2. Treatment with PBT2 was associated with multiple stress responses in both K. pneumoniae and E. coli. Significant changes in the transcription of transition metal ion homeostasis genes were observed in both strains.
2019-06-13 | GSE132637 | GEO
Project description:Objectives: Colistin remains a last-line treatment for multidrug-resistant Acinetobacter baumannii and combined use of colistin and carbapenems has shown synergistic effects against multidrug-resistant strains. In order to understand the bacterial responses to these antibiotics we analysed the transcriptome of A. baumannii following exposure to each.
2014-11-30 | GSE62794 | GEO
Project description:Colistin is a crucial last-line drug used for the treatment of life-threatening infections caused by multi-drug resistant strains of the Gram-negative bacteria, Acinetobacter baumannii. However, colistin resistant A. baumannii isolates can be isolated following failed colistin therapy. Resistance is most often mediated by the addition of phosphoethanolamine (pEtN) to lipid A by PmrC, following missense mutations in the pmrCAB operon encoding PmrC and the two-component signal transduction system PmrA/PmrB. We recovered an isogenic pair of A. baumannii isolates from a single patient before (6009-1) and after (6009-2) failed colistin treatment that displayed low/intermediate and high levels of colistin resistance, respectively. To understand how increased colistin-resistance arose, we genome sequenced each isolate which revealed that 6009-2 had an extra copy of the insertion sequence element ISAba125 within a gene encoding an H-NS-family transcriptional regulator. Consequently, transcriptomic analysis of the clinical isolates identified was performed and more than 150 genes as differentially expressed in the colistin-resistant, hns mutant, 6009-2. Importantly, the expression of eptA, encoding a second lipid A-specific pEtN transferase, but not pmrC, was significantly increased in the hns mutant. This is the first time an H-NS-family transcriptional regulator has been associated with a pEtN transferase and colistin resistance.
2018-02-19 | GSE107964 | GEO
Project description:Comparative Genomic and Transcriptomic Characterization of Colistin-Resistant Acinetobacter baumannii
2019-01-23 | GSE109951 | GEO
Project description:Colistin sulfate (polymixin E) is an antibiotic prescribed with resurging frequency for multidrug resistant gram negative bacterial infections. It is associated with nephrotoxicity in humans in up to 33% of cases. Little is known regarding genes involved in colistin nephrotoxicity. A murine model of colistin-mediated kidney injury was developed. C57/BL6 mice were administered saline or colistin at a dose of 16mg/kg/day in 2 divided doses. An Illumina gene expression array was performed on kidney RNA harvested 72 hours after first colistin dose to identify differentially expressed genes early in drug treatment. Array platform was MouseWG-6, 48,000 probes. Drug given intraperitoneal.
2013-11-05 | GSE46410 | GEO