Structure-activity relationships of hGlyrichin-derived antibacterial peptides

Objective: To study the relationship between changes of primary structure and antibacterial activity of hGlyrichin-derived antibacterial peptides.Methods: On the basis of functional peptide CM19 derived from hGlyrichin,five peptides were designed and synthesized by substitution,replacement,deletion and rearrangement according to the feature of antimicrobial peptide and known structure-activity relationship.The antibacterial activities of these peptides were detected using the methods bytube-testing and plating.Results: The first cysteine at the N-terminal of CM19 peptide was necessary for maintaining the antibacterial activity;rearrangement of amino acids abolished the activity;seven amino acids at C-terminal of CM19 had no antibacterial activity;randomly increasing positive charges by replacing amino acids with positively charged amino acids did not improve antibacterial activity.The peptide,CM12,had broad-spectrum antibacterial activity against both normal bacteria and drug resistant bacteria.Conclusion: Amino acids substitution,deletion and rearrangement have obvious influence on the antibacterial activities of hGlryichin-derived antimibacterial peptides.