Cell-Penetrating Peptide Induced Superstructures Triggering Highly Efficient Antibacterial Activity.

To endow non-antibacterial molecules with highly efficient bactericide activity is an important but challenging issue. Herein, a kind of cell-penetrating peptide octa-arginine (R8) is found to be effective in activating antibacterial ability when assembling with anionic surfactant sodium dodecyl sulfate (SDS), while individual R8 or SDS shows poor or no antibacterial ability. By combined electrostatic, hydrogen bond, and hydrophobic interactions, R8 and SDS associate into wormlike micelle and lamellar structure by forming supramolecular self-assembling units, depending on their charge ratio (CR). The lamellar aggregates show particularly high antibacterial activities against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). Interestingly, E. coli and S. aureus are killed by membrane-disrupting and membrane-penetrating mechanisms, respectively. Furthermore, in vivo experiments evidence that the R8/SDS lamellar aggregates accelerate the recovery of bacteria-infected wounds, wherein the reduced inflammation and promoted angiogenesis are clearly presented. This study proves that highly efficient bactericidal activity is triggered by the synergistic action of penetrating peptide and anionic amphiphiles, thus providing a new strategy to realize highly efficient and targetable antibacterial application.