Screening of quorum sensing and biofilm inhibitors among pseudomonas aeruginosa clinical isolates

Abstract

Quorum sensing (QS) is a process that enables bacteria to communicate using secreted small pheromone-like signaling molecules called autoinducers (AIs). This process enables a population of bacteria to regulate gene expression collectively. These quorum sensing systems regulates biofilm formation, virulence factors expression, bioluminescence, motility patterns, exopolysaccharide production, antifungal or antibiotic production, endoglucanase production, pigmentation, competence, plasmid conjugal transfer and cross-signaling between strains and species. P. aeruginosa is an important and very dangerous opportunistic pathogen causing many fatal infections in patients with serious medical conditions. P. aeruginosa is associated with nosocomial infections mainly in immunocompromised patients, and it is rated the third-most-common microorganism associated with hospital-acquired infections representing about 10-15% of nosocomial infections recorded globally. Moreover, qRT-PCR revealed a significant reduction in expression of quorum sensing genes in virulence inhibitors-treated P. aeruginosa in comparison with untreated bacteria. Virulence inhibitors could play a role in reduction of Pseudomonas quorum sensing-dependent virulence factors production such as biofilm production, and therefore affect its pathogenesis in the host.