Exploring the agricultural potential of AgNPs/PlyB221 endolysin bioconjugates as enhanced biocontrol agents

Understanding the formation of corona proteins on AgNPs (silver nanoparticles) is crucial for the development of therapeutic platforms aimed at selectively eliminating super-resistant bacteria. The insights gained from this study can guide the design and optimization of innovative strategies targeting super-resistant bacteria by leveraging the characteristics and behavior of corona proteins on AgNPs. In this study we developed novel nanobioconjugates combining AgNPs and PlyB221, an endolysin bacteriophage, and investigated the protein corona formation, as well as their activity against Bacillus cereus. The results demonstrate that proteins bind to the surface of the AgNPs, evident from a decrease in the surface plasmon resonance (SPR) peak absorption of the AgNPs and a shift in the maximum peak wavelength from 396 nm to 420 nm. Furthermore, DLS measurements reveal an increase in the hydrodynamic diameter of AgNPs from 4 nm to a plateau of approximately 2000 nm, accompanied by a change in zeta potential from −30 mV to −15 mV. These findings suggest that AgNPs are encased by proteins through electrostatic interactions. The AgNPs/PlyB221 complex effectively reduced the turbidity of Bacillus cereus by 80 %, at a concentration of 8.125 x 10−6 M. The implications of these findings are significant for the development of theranostic platforms for agricultural use. They provide valuable insights into designing effective strategies to combat super-resistant bacteria using corona proteins on AgNPs.