Project description:In the present study, we employed Affymetrix Pseudomonas aeruginosa GeneChip arrays to investigate global gene expression profiles during the cellular response of Pseudomonas aeruginosa to sodium hypochlorite Keywords: Antimicrobial response
Project description:Pseudomonas aeruginosa is a common bacteria leading to exacerbations of chronic obstructive pulmonary disease (COPD) patients while this bacteria can be easily eradicated by the immune systems of healthy individuals. Human airway organoids derived from healthy individuals and COPD patients were infected with pseudomonas aeruginosa. This project aims (1) to understand the differences in gene expressions in healthy and COPD airway organoids during stable condition, without infection and (2) to investigate differential pathogenic mechanism (i.e. antimicrobial defense) of pseudomonoas aeruginosa infection in healthy and COPD populations. Three healthy donors and three COPD patients were included in this study and samples were collected with and without pseudomonas aeruginosa infection.
Project description:Pseudomonas aeruginosa is a gram negative, opportunistic pathogen, which is the major cause of corneal infections in India and worldwide. Being categorised in the critical group of antibiotic resistant species, it has prompted significance rise in research to develop alternative therapeutics. One such alternative to combat bacterial infections is antimicrobial peptides (AMPs). This study aims to investigate the role of S100A12, a host defence peptide against PAO1. It was also seen to inhibit the bacterial growth of PAO1 in vitro as seen from the colony forming units. Our study sheds light on how S100A12 impacts Pseudomonas and that it might have the potential to be used as therapeutic intervention in addition to antibiotics in future.
Project description:Colistin is an important cationic antimicrobial peptide (CAMP) in the fight against Pseudomonas aeruginosa infection within the cystic fibrosis (CF) lungs. The effects of sub-inhibitory colistin on gene expression in P. aeruginosa were investigated by transcriptome microarray and functional analysis. Analysis revealed an alteration in the expression of 60 genes in total from a variety of pathways. Genes associated with bacterial chronic colonisation and virulence such as response to osmotic stress, motility, and biofilm formation, as well as those associated with LPS modification and quorum sensing are the most highly represented. Most striking among these is the upregulation of the PQS biosynthesis operon including pqsH, pqsE, and the anthranilate biosynthetic genes phnAB. Early activation of this central component of the QS-network may represent a switch to a more robust population, with increased fitness in the competitive environment of the CF-lung.
Project description:Using in vitro directed evolution, we show that mismatch repair-deficient Pseudomonas aeruginosa can engage novel resistance mechanisms to ceftazidime-avibactam.
Project description:Colistin is an important cationic antimicrobial peptide (CAMP) in the fight against Pseudomonas aeruginosa infection within the cystic fibrosis (CF) lungs. The effects of sub-inhibitory colistin on gene expression in P. aeruginosa were investigated by transcriptome microarray and functional analysis. Analysis revealed an alteration in the expression of 60 genes in total from a variety of pathways. Genes associated with bacterial chronic colonisation and virulence such as response to osmotic stress, motility, and biofilm formation, as well as those associated with LPS modification and quorum sensing are the most highly represented. Most striking among these is the upregulation of the PQS biosynthesis operon including pqsH, pqsE, and the anthranilate biosynthetic genes phnAB. Early activation of this central component of the QS-network may represent a switch to a more robust population, with increased fitness in the competitive environment of the CF-lung. Experiment Overall Design: Three independent cultures of the P. aeruginosa strain PAO1 were exposed to 0.15 µg colistin mlâ1. The untreated and treated samples were grown from OD600 0.05 to 0.8 and subsequently total RNA was extracted using the Ambion RiboPureTm- Bacteria kit according to the manufacturerâs instructions.
Project description:In this experiment the transcriptional response of the opportunistic human pathogen Pseudomonas aeruginosa towards physiological concentrations of the major human host defense peptide LL-37 was investigated using microarrays. To this aim, three independent cultures of P. aeruginosa PAO1 were grown until mid-log phase in Mueller-Hinton broth and subsequently incubated with either sublethal LL-37 concencentrations (20 M-5g/ml) or without peptide for 2 h at 37 M-0C following RNA extraction and microarray analysis.
Project description:Methylrhodomelol (1) is a bromophenol from the red alga Vertebrata lanosa (L.) T.A.Christensen that has been associated with antimicrobial properties. Aim of the current study was therefore, to assess the antimicrobial potential of this compound in more detail against the gram-negative pathogen Pseudomonas aeruginosa. 1 exerted weak bacteriostatic activity against different strains when grown in minimal medium, whereas other phenolics were inactive. In addition, 1 (35 and 10 µg/mL) markedly enhanced the susceptibility of multidrug resistant P. aeruginosa towards the aminoglycoside gentamicin, while it did not affect the viability of Vero kidney cells up to 100 µM. Finally, pyoverdine release was reduced in bacteria treated at sub-inhibitory concentration, but no effect on other virulence factors was observed. Transcriptome analysis of treated versus untreated P. aeruginosa indicated an interference of 1 with bacterial carbon and energy metabolism, which was corroborated by RT-qPCR and decreased ATP-levels in treated bacteria.
Project description:This project investigates the proteomic response of Pseudomonas aeruginosa PAO1 and Staphylococcus aureus to postbiotic metabolites derived from Lacticaseibacillus rhamnosus. Bacterial cultures were exposed to sub-MIC concentrations of L. rhamnosus cell-free supernatant (CFS) or lactic acid (LA) for 6 h, and intracellular proteins were extracted for quantitative label-free proteomics using HPLC–MS/MS. The dataset includes RAW mass spectrometry data and MaxQuant output files. The aim of this study is to compare stress responses triggered by complex postbiotic mixtures versus LA alone, focusing on antimicrobial and antibiofilm potential.
Project description:We carried out an experimental evolution in human serum as an ex-vivo model and screened evolved lines for the evolution of resistance phenotypes towards two anti-virulence treatments, gallium and flucytosine, which both target the iron scavenging pyoverdine of Pseudomonas aeruginosa (each at 2 different doses). We performed whole-genome sequencing of 16 evolved clones from the different treatment regimes .
