Natural Inhibitors of Quorum-Sensing Factors: a Novel Strategy to Control Pathogenic Bacteria

Abstract

The inappropriate and widespread use of conventional antibiotics for the treatment of infectious diseases has resulted in the emergence of resistant strains of pathogenic microorganisms, and this, in turn, has promoted the search for antibacterial metabolites with new mechanisms of action. The use of antivirulence agents, which focus on attenuating bacterial pathogenicity rather than affecting cell viability, represents an alternate and interesting approach for treating bacterial infections. Quorum sensing is one of the main targets of antivirulence agents, since it plays a fundamental role in the expression of virulence and resistance factors during the infection process. Considering that natural products represent a potentially important source of antivirulence agents, this review describes secondary metabolites from plants and microorganisms reported to inhibit quorum sensing, particularly over the opportunistic pathogen Pseudomonas aeruginosa, one of the most problematic human pathogens and one that, because of its intrinsic resistance to antibiotics, has been adopted as a model for the discovery of new antimicrobial agents.