Affiliation: | 1. National Institute of Health Sciences, 3-25-26, Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501 Japan
Graduate School of Medical Health Sciences, Yokohama City University, Yokohama-shi, Kanagawa, 230-0045 Japan;2. National Institute of Health Sciences, 3-25-26, Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501 Japan;3. National Institute of Health Sciences, 3-25-26, Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa, 210-9501 Japan
Department of Nutrition, Chiba Prefectural University of Health Sciences University, 2-10-1 Wakaba, Mihama-ku, Chiba, 261-0014 Japan |
Abstract: | Magainin 2 ( Mag 2 ), which is isolated from the skin of frogs, is a representative antimicrobial peptide (AMP), exerts its antimicrobial activity via microbial membrane disruption. It has been reported that both the amphipathicity and helical structure of Mag 2 play an important role in its antimicrobial activity. In this study, we revealed that the sequence of 17 amino acid residues in Mag 2 (peptide 7 ) is required to exert sufficient activity. We also designed a set of Mag 2 derivatives, based on enhancement of helicity and/or amphipathicity, by incorporation of α,α-disubstituted amino acid residues into the Mag 2 fragment, and evaluated their preferred secondary structures and their antimicrobial activities against both Gram-positive and Gram-negative bacteria. As a result, peptide 11 formed a stable helical structure in solution, and possessed potent antimicrobial activities against both Gram-positive and Gram-negative bacteria without significant cytotoxicity. |