Antibacterial mechanism by copper ion and copper complex against the Gram positive and negative bacteria

Abstract

Antibacterial activities of Cu ion and Cu complex for the Gram-positive and Gram-negative bacterial cell walls, membrane and cytoplasm were examined on the basis of being more pronounced with the bacteriostatic action. The antibacterial actions resulted in the various damages of biosynthesis by Cu-TP/TG enzymes bonds, Cu complex formations and reactive oxygen species(ROS) in the peptidoglycan layer of Gram-positive cell wall, the damages of the outer membrane due to protein deficiency, the inhibitions by Cu⁺, ･OH, OH^－ occurring with Haber-Weiss and Fenton reactions in the cell membrane, and the cleavages of DNA and RNA by DNA-chain breaking and Cu-complex formations in DNA bases due to Cu²⁺ and H₂O₂ in the cytoplasm.