Abstract
Abstract With the increasing of antibiotic resistant pathogens, antimicrobial peptide is the optimal candidate for treating these pathogens. However, most of antimicrobial peptides reduced its ability under high salt concentration. Herein, we reported a new approach to diminish the influence of salinity for AMPs, through end tagging with the bulky aromatic amino acid, Nal (β-naphthylalanine) at the terminus of peptide. S1 (KKWRKWLAKK), a 10-mer peptide derived from W5K/A9W (KKWRKWLKWLAKK) originated from PEM2. Unfortunately, S1 lost its bactericidal performance, but hemolytic ability got a significant decline. Therefore, we hypothesized that the length of antimicrobial peptide affects the bactericidal function. In this study, adding several Nal at the terminus of S1 to form the hydrophobic end tagging. Determine the length of peptide or the end tagging, which is the pivotal one in determining the antimicrobial functions. The results indicated that end tagging length preserves antimicrobial ability of the peptide at high salinity. This result can be applied in any salt-sensitive antimicrobial peptide, conjugated a hydrophobic end tagging at the terminus can solve this problem. This easy strategy promote the antimicrobial peptide can exert its best effect on high salt condition, mammalian physiology or any salt-related situation.