Control of quorum sensing and virulence factors of Pseudomonas aeruginosa using phenylalanine arginyl -naphthylamide.

This study aims to find out the impact of efflux pump inhibitor, PAN, on QS and virulence attributes in clinical isolates of P. aeruginosa. P. aeruginosa isolates were purified from urine and wound samples and the antimicrobial susceptibility was carried out by disc diffusion method. The multidrug resistant and the virulent isolates U16, U21, W19 and W23 were selected. PAN enhanced their susceptibility to most antimicrobial agents. PAN reduced QS signaling molecules N-3-oxo-dodecanoyl-L-homoserine lactone (C12-HSL) and N-butyryl-L-homoserine lactone (C4-HSL) without affecting bacterial viability. Moreover, PAN eliminated their virulence factors such as elastase, protease, pyocyanin and bacterial motility. On the transcription level, PAN significantly (P<0.01) diminished the relative expression of QS cascade (lasI, lasR, rhlI, rhlR, pqsA, and pqsR) and QS regulated-type II secretory genes lasB (elastase) and toxA (exotoxin A) compared to the control untreated isolates U16 and U21. In addition, PAN eliminated the relative expression of pelA (exopolysaccharides) in U16 and U21 isolates. Hence, P. aeruginosa tested isolates became hypo-virulent upon using PAN. PAN significantly blocked QS circuit and inhibited the virulence factors expressed by clinical isolates of P. aeruginosa. PAN could be a prime substrate for developing QS inhibitors and prevention of P. aeruginosa pathogenicity. PMID: 27498852 [PubMed - as supplied by publisher]
Source: Journal of Medical Microbiology - Category: Microbiology Authors: Tags: J Med Microbiol Source Type: research