Pro does not have amide hydrogen, can not form hydrogen bonds in the chain, so it will break the alpha-helix in the polypeptide chain, resulting in a "nodule", which is the destroyer of alpha-helix. In order to study the effect of Pro on antimicrobial peptide activity, an antimicrobial peptide AM-3 with 25 amino acid residues was designed and synthesized. The only difference between AM-3 and AM-4, which had better antitumor activity and drug selectivity, was that AM-3 was Pro, AM-4 was Ahx. The results showed that there was no significant difference between AM-3 and AM-4 in the content of alpha-helix components, anti-tumor activity and hemolytic activity in vitro; fluorescence microscopy showed that AM-3 also had rapid and effective anti-tumor activity, and its killing ability to normal cells (NIH-3T3) was lower than that of tumor cells (HEPG-2), indicating that AM-3 also had certain anti-tumor activity. Selective toxicity.
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