The effect of structural modification of antimicrobial peptides on their antimicrobial activity, hemolytic activity, and plasma stability

J Pept Sci. 2021 May;27(5):e3306. doi: 10.1002/psc.3306. Epub 2021 Feb 7.

Abstract

In this article, a series of modifications were made on an antimicrobial peptide F2,5,12 W, including altering the amino acid sequence, introducing cysteine and other typical amino acids, developing peptide dimers via disulfide bonds, and conjugating with mPEG, in order to enhance the antimicrobial activity, plasma stability, and reduce the hemolytic activity of peptides. The results showed that mPEG conjugation could significantly improve the plasma stability and reduce the hemolytic activity of peptides, while the antimicrobial activity decreased meanwhile. However, altering the sequence of the peptide without changing its amino acid composition had little impact on its antimicrobial activity and plasma stability. The introduction of cysteine enhanced the plasma stability of peptides conspicuously, but at the same time, the increased hydrophobicity of peptides increased their hemolysis. The antimicrobial mechanism and cytotoxicity of the peptides with relatively high antimicrobial activity were also studied. In general, this study provided some ideas for the rational design and structure optimization of antimicrobial peptides.

Keywords: antimicrobial activity; antimicrobial peptide; hemolytic activity; plasma stability; structural modification.

MeSH terms

  • Anti-Bacterial Agents / blood
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Escherichia coli / drug effects*
  • Hemolysis / drug effects
  • Humans
  • Microbial Sensitivity Tests
  • Pore Forming Cytotoxic Proteins / blood
  • Pore Forming Cytotoxic Proteins / chemistry
  • Pore Forming Cytotoxic Proteins / pharmacology*
  • Staphylococcus aureus / drug effects*

Substances

  • Anti-Bacterial Agents
  • Pore Forming Cytotoxic Proteins