The role of biosynthesized zinc oxide nanoparticles in modulating the expression of virulence factors in multidrug-resistant Klebsiellapneumoniae.

The rapid proliferation of multidrug-resistant bacteria has emerged as a pressing threat to global public health, necessitating the development of innovative antimicrobial approaches. The aim of this study was to biosynthesize zinc oxide nanoparticles from the flower extract of Malva sylvestris and to investigate their effect on virulence genes (mrkD, uge, wabG, luxS, fimH) in multidrug-resistant Klebsiella pneumoniae. Techniques used for characterizing nanoparticles include (Ultraviolet-Visible, Fourier transform infra-red, Energy dispersive X-Ray) spectroscopy, X-Ray Diffraction, Scanning and Transmission electron microscopes. Characterizations revealed that zinc oxide nanoparticles exhibit semispherical to hexagonal crystalline structures. Furthermore, we used quantitative real-time PCR to investigate the impact of zinc oxide nanoparticles on the expression of virulence genes (mrkD, uge, wabG, luxS, fimH). The antimicrobial assays revealed that zinc oxide nanoparticles produced significant inhibitory effects against MDR Klebsiella pneumoniae at concentrations above 200 μg/ml. The expression levels of (mrkD, uge, wabG, luxS, fimH) genes were downregulated below a ratio of 1.0 in the isolates treated with sub-inhibitory concentrations of zinc oxide nanoparticles. The results highlight the viability of utilizing Malva sylvestris in eco-friendly biosynthesis of zinc oxide nanoparticles, which afford antibacterial activity through their effects on gene expression, as well as their application in biomedicine for controlling MDR infections.