Evaluation of the inhibitory effects of human serum components on bactericidal activity of human beta defensin 3

The Central Hinge Link Truncation of the Antimicrobial Peptide Fowlicidin-3 Enhances Its Cell Selectivity without Antibacterial Activity Loss

“…2, Fow-3 and Fow-3(1-19) showed significant hemolytic activity in a dose-dependent manner. Fow-3 displayed stronger hemolytic activity than its derivatives, and its hemolysis reached 88.1% at the concentration of 256 M. Fow-3(1-19) also displayed higher hemolytic activity than the other three peptide derivatives, and 38.9% hemolysis was observed at the concentration of 256 M. Fow-3(1-15), Fow-3 (19)(20)(21)(22)(23)(24)(25)(26)(27), and Fow-3(1-15-20-27) showed no obvious hemolytic activity even at 256 M (less than 5% hemolysis), suggesting that the 4-amino-acid segment from position 16 to position 19 in the central link region is of vital importance in maintaining the hemolytic activity of Fow-3. Melittin, which is known to have strong antimicrobial activities against all bacteria, caused complete hemolysis at the concentrations of more than 32 m⌴.…”

“…The antimicrobial activity of the designed peptides was tested against three Gram-positive and five Gram-negative bacterial strains. As shown in Table 2, Fow-3 was potent against all strains, with MIC values in the range of 2 to 4 M. Fow-3(1-15), the analog containing only the N-terminal segment of Fow-3, exhibited poor efficacy against all the tested bacterial strains (MICs of Ն64 M), whereas no antimicrobial activity for tested microorganisms (Ͼ128 M) was observed for Fow-3(1-19) or Fow-3 (19)(20)(21)(22)(23)(24)(25)(26)(27). The MIC values of Fow-3 (1-15-20-27) for the tested bacteria are approximated to those of the parent peptide.…”

“…Fow-3(1-19) displayed the highest cytotoxic activity in the concentration range of 8 to 128 M. At the highest concentration of 256 M, the cell survival rates seen with Fow-3 and Fow-3(1-19) were less than 30%. Fow-3(1-15), Fow-3 (19)(20)(21)(22)(23)(24)(25)(26)(27), and Fow-3(1-15-20-27) displayed significantly lower cytotoxic activity on cells than Fow-3 and Fow-3(1-19). At the con- Stability of peptides.…”

“…The antibacterial activities of Fow-3(1-15), Fow-3(1-19), and Fow-3(20-27) were attenuated or even nearly lost, and Fow-3(1-15-20-27) displayed antibacterial activity similar to that of Fow-3. Fow-3 (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) showed obvious cytotoxicity compared with other analogs, which demonstrated that the central hinge link (-AGIN-) was crucial to the cytotoxicity of the peptide. Fow-3 (1-15-20-27) showed good tolerance to salt ions and a considerably higher level of cell selectivity than Fow-3.…”

Characterization of Antibacterial Activity and Synergistic Effect of Cationic Antibacterial Peptide-resin Conjugates

“…15 Albumin was known to have no effect on the growth of bacteria and the decrease of antibacterial activity of the peptide was mainly due to competing binding of the peptide to albumin. 16 Thus, we measured antibacterial activity of conjugate 1 in the presence of human serum albumin.…”