Insights into the Action Mechanism of the Antimicrobial Peptide Lasioglossin III.

摘要: Lasioglossin III (LL-III) is a cationic antimicrobial peptide derived from the venom of eusocial bee Lasioglossum laticeps. LL-III extremely toxic to both Gram-positive and Gram-negative bacteria, it exhibits antifungal as well antitumor activity. Moreover, shows low hemolytic activity, has almost no effects on eukaryotic cells. However, molecular basis mechanism action still unclear. In this study, we characterized by means calorimetric (DSC) spectroscopic (CD, fluorescence) techniques its interaction with liposomes composed mixture 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) 1-palmitoyl-2-oleoyl-sn-glycero-3-rac-phosphoglycerol (POPG) lipids model negatively charged membrane pathogens. For comparison, uncharged POPC was also studied. Our data showed that preferentially interacted anionic in POPC/POPG induces formation lipid domains. Furthermore, leakage experiments could permeabilize membrane. Interestingly, our DSC results peptide-membrane occurs non-disruptive manner, indicating an intracellular targeting mode for peptide. Consistent hypothesis, gel-retardation assay interact plasmid DNA, suggesting possible target.