Fighting multidrug-resistant Enterococcus faecalis via interfering with virulence factors using green synthesized nanoparticles

Abstract

This study aims to synthesize silver nanoparticles by the green method and test it against specific virulence factors in multi-drug resistant Enterococcus faecalis bacteria. virulence factors of E. faecalis clinical isolates were determined and the most potent isolate was selected for further investigations. The prepared Ag-NPs were characterized using UV spectroscopy, FTIR spectroscopy, dynamic light scattering, and transmission electron microscopy (TEM). The result revealed the concentration of 0.0625 mg/ml Ag-NPs was significantly reducing virulence factors in multidrug-resistant E. faecalis without affecting planktonic cell growth. UV-Visible spectroscopy characterization revealed a characteristic surface Plasmon band [SPR] at a wavelength ranging from 256 to 345 and 510 nm in the prepared Ag-NPs. dynamic light scattering indicated it tended to an electrostatic attraction between nanoparticles in the prepared solution. TEM images revealed the average size of Ag-NPs were prepared to be 28.8 nm and the shape was spherical. Green synthesized Ag-NPs have the ability to combat multi-drug-resistant E. faecalis via reducing virulence factors, which is considered a good approach toward resolving the multidrug resistance crisis.

Keywords: Enterococcus faecalis; Green synthesis; Nanoparticles; Quorum sensing system -multi-drug resistant bacteria; Virulence factors.