The effect of Zinc Oxide nanoparticles on Pseudomonas aeruginosa biofilm formation and virulence genes expression

Introduction: Due to increased resistance to antimicrobial agents, infectious diseases remain a public health problem worldwide. The current study was designed to examine the effect of Zinc Oxide nanoparticles (ZnO–np) against the biofilm formation ability of P. aeruginosa clinical isolates and to study its effect on the expression level of the genes involved in biofilm formation and virulence factors production. Methodology: The MIC of ZnO–np against P. aeruginosa was determined by the broth micro dilution method. The effect of ZnO–np on the biofilm-forming isolates of P. aeruginosa was monitored by the microtiter plate method. P. aeruginosa isolates were tested for the expression of different biofilm and virulence genes using real-time rt-PCR. Results: ZnO–np significantly down-regulated the expression level of all biofilm and virulence genes of P. aeruginosa clinical isolates except the toxA gene. Conclusions: This study demonstrates the promising use of ZnO–np as an anti-biofilm and anti-virulence compound.