The application provides polypeptide Pv26-3 with
antimicrobial activity, belonging to the technical field of
genetic engineering drugs. In the polypeptide Pv26-3,
tryptophan W replaces the 7th, 11th,21st and 25th sites in the
amino acid sequence of a parent molecule Pv26, and
lysine K replaces amino acids at the 1st, 12th, 20th and 24th sites, thereby enhancing the hydrophobicity and positive charge of the parent molecule Pv26. Since a hydrophobic group plays a key role in the process of inserting
antimicrobial peptide into a
cell membrane, the improvement of hydrophobicity is beneficial to the
antimicrobial effect of the antimicrobial
peptide; the antimicrobial
peptide is bonded to the membrane by
electrostatic interaction, so as to promote the combination of the hydrophobic group into the membrane, and then the
membrane structure is destroyed to cause
cell death, so that positive charge is the key factor affecting the binding of the antimicrobial peptide and the membrane; by improving hydrophobicity and positive charge, the
binding ability of the antimicrobial peptide and the membrane can be enhanced, the antimicrobial activity and
antibacterial effect of antimicrobial peptide can be improved, and at the same time, the action concentration of antimicrobial peptide is lowered.