Photochemically-Generated Silver Chloride Nanoparticles Stabilized by a Peptide Inhibitor of Cell Division and Its Antimicrobial Properties

Abstract

The 40 amino acid residues peptide MciZ (Mother Cell Inhibitor of FtsZ) represents a promising antibacterial agent as it is an effective inhibitor of bacterial cell division, Z-ring formation and localization. However, its efficacy is limited to Gram-positive bacteria as MciZ is unable to penetrate into Gram-negative organisms. In this study, we report the synthesis of plasmonic silver chloride nanoparticles stabilized by MciZ (NP/MciZ). NP/MciZ were synthesized using a fast and green route under blue light irradiation. Electron microscopy showed that NP/MciZ were enveloped by a peptide layer responsible for colloidal stability. X-ray diffraction analysis showed that silver chloride nanoparticles were crystalline in nature with small proportion of metallic silver. NP/MciZ showed a dose-dependent cytotoxicity against mammalian VERO cells. However, NP/MciZ exhibited remarkable antibacterial activity against Gram-positive bacterium B. megaterium comparable to MciZ. Furthermore, NP/MciZ showed similar antimicrobial activity against the Gram-negative bacterium E. coli and the yeast C. albicans. The photochemically-generated NP/MciZ presented here is a new organic–inorganic hybrid nanomaterial and has potential for biomedical or other applications.