Bacterial Infections and Mycoses Commons^™

Pseudomonas Aeruginosa Outer Membrane Vesicles Triggered By Human Mucosal Fluid And Lysozyme Can Prime Host Tissue Surfaces For Bacterial Adhesion, Matteo M. E. Metruccio, David J. Evans, Manal M. Gabriel, Jagath L. Kadurugamuwa, Suzanne M. J. Fleiszig

Faculty Publications & Research of the TUC College of Pharmacy

Pseudomonas aeruginosa is a leading cause of human morbidity and mortality that often targets epithelial surfaces. Host immunocompromise, or the presence of indwelling medical devices, including contact lenses, can predispose to infection. While medical devices are known to accumulate bacterial biofilms, it is not well understood why resistant epithelial surfaces become susceptible to P. aeruginosa. Many bacteria, including P. aeruginosa, release outer membrane vesicles (OMVs) in response to stress that can fuse with host cells to alter their function. Here, we tested the hypothesis that mucosal fluid can trigger OMV release to compromise an epithelial barrier. This was tested using …

Cytotoxic Clinical Isolates Of Pseudomonas Aeruginosa Identified During The Steroids For Corneal Ulcers Trial Show Elevated Resistance To Fluoroquinolones, Durga S. Borkar, Nisha R. Acharya, Chelsia Leong, Prajna Lalitha, Muthiah Srinivasan, Catherine E. Oldenburg, David J. Evans

Faculty Publications & Research of the TUC College of Pharmacy

Background: To determine the relationship between type three secretion genotype and fluoroquinolone resistance for P. aeruginosa strains isolated from microbial keratitis during the Steroids for Corneal Ulcers Trial (SCUT) and for two laboratory strains, PA103 and PAO1.

Methods: Confirmed P. aeruginosa isolates from the SCUT were divided into exoU(+) or exoU(−). The exoU(+) strains contained the gene encoding ExoU, a powerful phospholipase toxin delivered into host cells by the type three secretion system. Isolates were then assessed for susceptibility to fluoroquinolone, cephalosporin, and aminoglycoside antibiotics using disk diffusion assays. Etest was used to determine the MIC of moxifloxacin …