Project description:Pseudomonas aeruginosa is a leading cause of hospital acquired infections for which the development of new antibiotics is urgently needed. Unlike most enteric bacteria, P. aeruginosa lacks thymidine kinase and thymidine phosphorylase activity, and thus cannot scavenge exogenous thymine. An appealing strategy to selectively target P. aeruginosa while leaving the healthy microbiome largely intact would thus be to disrupt thymidine synthesis while providing exogenous thymine. However, this approach was previously intractable because known antibiotics that perturb thymidine synthesis are largely inactive against P. aeruginosa. Here, we characterize a novel dihydrofolate reductase inhibitor, fluorofolin, that exhibits significant activity against P. aeruginosa in culture and in a mouse thigh infection model. Fluorofolin is active against a wide range of clinical P. aeruginosa isolates resistant to known antibiotics, including critical antibiotic development priorities expressing the beta-lactamases KPC-5 and NDM-1. Importantly, in the presence of thymine supplementation, fluorofolin activity is selective for P. aeruginosa. Resistance to fluorofolin can emerge through overexpression of the efflux pumps MexCD-OprJ and MexEF-OprN. However, these mutants also decrease pathogenesis, in part due to increased export of quorum sensing precursors leading to decreased virulence factor production. Our findings thus demonstrate how understanding species-specific genetic differences and discovery of an antibiotic with a widely conserved target can enable selective targeting of important pathogens while revealing new tradeoffs between resistance and pathogenesis.
2024-02-07 | GSE249862 | GEO
Project description:First detection in Spain of NDM-1-producing Pseudomonas aeruginosa in two patients transferred from Ukraine to a university hospital
Project description:Analysis of a SigX knockout mutant of Pseudomonas aeruginosa H103 strain in minimal medium with glucose as carbon source (M9G). SigX, one of the 19 extra-cytoplasmic function sigma factors of P. aeruginosa, was only known to be involved in transcription of the gene encoding the major outer membrane protein OprF in Pseudomonas aeruginosa. Deletion of the ECF sigma factor sigX gene provide insights into the SigX role in several virulence and biofilm- related phenotypes in Pseudomonas aeruginosa.
Project description:Analysis of a SigX knockout mutant of Pseudomonas aeruginosa H103 strain in minimal medium with glucose as carbon source (M9G). SigX, one of the 19 extra-cytoplasmic function sigma factors of P. aeruginosa, was only known to be involved in transcription of the gene encoding the major outer membrane protein OprF in Pseudomonas aeruginosa. Deletion of the ECF sigma factor sigX gene provide insights into the SigX role in several virulence and biofilm- related phenotypes in Pseudomonas aeruginosa. To better understand the cellular function of SigX, a deletion mutant of the sigX gene (PAOSX) was generated and its expression profile was compared with parental strain Pseudomonas aeruginosa H103. To this end, H103 and a sigX mutant were cultured in M9G, in which their growth are similar. Three independant biological replicate were taken for the RNA extraction and hybridization on affymetrix array in the middle of the exponential growth phase.
Project description:Pseudomonas aeruginosa is one of the most frequent pathogen dominant in complicated urinary tract infections (UTI). To unravel the adaptation strategies of P. aeruginosa to the conditions in the urinary tract and to define the underlying regulatory network an artificial growth system mimicking the conditions in the urinary tract was established. Transcriptome analyses were used to investigate the physiological status of P. aeruginosa under this conditions.
Project description:Pseudomonas aeruginosa was grown in open circuit (control) and closed circuit (current collecting) to observe the difference in extracellular electron transfer (EET) mechanisms. mRNA was extracted, amplified and used on Combimatrix custom arrays to obtain
2010-07-08 | E-MTAB-269 | biostudies-arrayexpress
Project description:Emergence and clonal spread of NDM-1-producing Pseudomonas aeruginosa isolates in Greece