Biosynthesized ZnO-CuO Nanocomposite for Biofilm Formation of Proteus mirabilisupon LuxS Gene Expression

Abstract

Proteus mirabilis has been identified as the third most frequent reason for catheter-associated urinary tract infections. The production of urease significantly enhances the force of catheter blockage caused by biofilm formation. Because biofilms are important virulence factors that make antibiotics less potent, it is becoming increasingly important to develop novel alternative antibiotics. In addition to the unique properties they possess, nanoparticles made from metal oxide are currently attracting considerable attention as possible antibacterials. This research aims to explore the potential anti-biofilm properties of green manufactured ZnO-CuO nanoparticles generated by P. mirabilis. By synthesizing reductive enzymes, bacterial cells can participate in the biosynthesis process. This study explores whether green synthesized ZnO-CuO nanoparticles can work as an anti-biofilm agent formed by P. mirabilis. These nanoparticles were generated using Bacteriocins to determine their effectiveness against bacteria, which were partially purified and showed antimicrobial activity against Gram-negative bacteria of P. mirabilis. AFM, TEM, FESEM, XRD, and ultraviolet (UV)–visible spectroscopy were used to analyze the biosynthesized nanoparticles to ascertain their chemical and physical characteristics. XRD verified the hexagonal structure, TEM demonstrated a size range of 96.00 nm, and FESEM verified the surface morphology. The dispersion and roughness of the nanoparticles are shown through AFM examination. The produced nanoparticles’ UV-visible spectra displayed a maximum peak at 287 and 232 nm. When applied to strains (wild-type) of Proteus mirabilis (multidrug-resistant), copper and zinc nanoparticles had notable biofilm inhibitory effects. Weak biofilm production has been demonstrated by bacteria that effectively generate biofilms, following incubation with 128 μg/mL subminimum inhibitory concentrations (MICs) of CuO nanoparticles for 24 and 48 h at 37 °C. Following treatment with the ZnO-CuO nanocomposite of these strains, downregulation alterations in LuxS expression were detected by utilizing a real-time PCR process. After this, isolates were treated with the nanocomposite, and downregulated shifts in LuxS expression were found by utilizing the real-time PCR technique in contrast with the isolates that were not treated. Zinc oxide (ZnO) nanoparticles can be utilized as antibacterial agents in a concentration-dependent manner, aligning with all observed findings. The present research demonstrates that green synthesized copper oxide–zinc oxide nanocomposites are effective anti-biofilm agents against P. mirabilis. Their noteworthy downregulation of LuxS gene expression successfully prevents biofilm formation and swarming motility.