The chemical, physical, and biological properties of bacteria developing resistance, in both humans and plants, are mostly unknown at the single cell level. However biomechanical properties have been shown to contribute to bacteria becoming infectious. Thus the ability to probe changes in stiffness, adhesion, binding interactions and molecular traits of individual bacteria is of great interest to develop a new generation of more potent, yet sustainable, pesticides.
Our study aims to investigate the mechanical and chemical properties of bacterial systems and their cell walls. Building upon this fundamental understanding of the cells, we also investigate the biophysicochemical responses associated to multivalent nanoparticle-based bactericide treatments on bacterial systems identified as pathogens in plant diseases. Here we focus on developing a novel protocol to support the design and accelerate the development of pesticides and treatments against Xanthomonas perforans, a strain known for causing bacterial spot in tomatoes and causing close to 50% losses in production. By comparing bacteria pre- and post-treatment with a multivalent silica core shell nanoparticle using a combination of Raman spectroscopy and atomic force microscopy (AFM)-based techniques, we identify attributes that can potentially serve as markers to track the bacterial response to the treatment. By exploring the local bacterial responses to treatment and correlating the results to conventional bioassays, we propose a new approach with exciting implications, such as potential clues for the development of more potent treatments for resistant bacteria.