Self-Assembled Peptide Nanofibrils Designed to Release Membrane-Lysing Antimicrobial Peptides

Membrane-disrupting antimicrobial peptides continue to attract increasing attention due to their potential to combat multidrug-resistant bacteria. However, some limitations are found in the success of clinical setting-based antimicrobial peptide agents, for instance, the poor stability of antimicrobial peptides in vivo and their short-term activity. Self-assembled peptide materials can improve the stability of antimicrobial peptides, but the biosafety of peptide-based materials is the main concern, although they are considered to be biocompatible, because some peptide aggregates would possibly induce protein misfolding, which could be related to amyloid-related diseases. Therefore, in this work, we designed two peptides and constructed peptide-based nanofibrils by self-assembly before its utilization. It is found that the fibrils could release the antimicrobial peptide by disassembly for microbial membrane lysis in the presence of bacteria. The designed peptide-based fibrils presented a good and long-term antimicrobial activity with bacterial membrane disruption and the efflux of calcium from bacteria. Furthermore, it could be used to construct hybrid macrofilms displaying low cytotoxicity, low hemolytic activity, and good biocompatibility. The innovative design strategy could be beneficial for the development of smart antimicrobial nanomaterials.