Self-Assembled Nanoparticles of Symmetrical Cationic Peptide Against Citrus Pathogenic Bacteria

The increasing drug resistance of phytopathogenic bacteria to conventional bactericides has driven the necessity for exploring new alternatives with a lower tendency to develop bacterial resistance. Here, we report a novel cationic symmetrical peptide P5VP5 (Ac-RLIRKVKRILR-NH2 that enables self-assembly to form nanoparticles with excellent thermal stability. An in vitro assay showed that P5VP5 nanoparticles exhibited excellent antibacterial activity against Xanthomonas axonopodis pv citri with a MIC value of 20 mu M. Meanwhile, under an in planta condition, treatment with peptide nanoparticles demonstrated the highest ability to reduce the development of citrus canker lesions in leaves. Moreover, the nanoparticles could destroy the biofilm formation, damage the cell membranes, and affect the cell membrane permeability, ultimately leading to the death of bacteria. Taken together, these nanoparticles are a promising antibacterial agent that can be used to control citrus canker and other plant diseases caused by bacteria.