In Pseudomonas aeruginosa, the production of many secreted virulence factors is controlled by a quorum-sensing (QS) circuit, constituted of transcriptional activators (LasR, RhlR, PqsR) and their cognate signaling molecules (3-oxo-C12-HSL, C4-HSL, PQS). QS is a cooperative behavior that is beneficial to a population but can be exploited by "QS-cheaters", individuals which do not respond to the ...

virulent and resistant strains pseudomonas aeruginosa ( p. aeruginosa) is one of the most important cause of utis in pediatrics. the present study was carried to investigate the frequency of virulence factors in the multi-drug resistant strains of  p. aeruginosa isolated from pediatrics hospitalized due to the utis. one - hundred and forty three urine samples were collected from pediatric patie...

The las and rhl quorum sensing (QS) systems regulate the expression of several genes in response to cell density changes in Pseudomonas aeruginosa. Many of these genes encode surface-associated or secreted virulence factors. Proteins from stationary phase culture supernatants were collected from wild-type and P. aeruginosa PAO1 mutants deficient in one or more of the lasRI, rhlRI and vfr genes ...

BACKGROUND AND OBJECTIVES This study was designed to evaluate the activity of Quercus infectoria galls extract (QIFGE) on virulence factor production and inhibition of quorum sensing (QS) in Pseudomonas aeruginosa. MATERIALS AND METHODS Minimum inhibitory concentration (MIC) of QIFGE against 5 strains of P. aeruginosa was determined. The extract at sub-MIC was used to determine biofilm format...

The genetic structure of a population of Pseudomonas aeruginosa, isolated from patients with keratitis, endophthalmitis, and contact lens-associated red eye, contact lens storage cases, urine, ear, blood, lungs, wounds, feces, and the environment was determined by multilocus enzyme electrophoresis. The presence and characteristics of virulence factors were determined by restriction fragment len...