Unraveling the antifungal activity of a South American rattlesnake toxin crotamine

摘要: Crotamine is a highly basic peptide from the venom of Crotalus durissus terrificus rattlesnake. Its common gene ancestry and structural similarity with β-defensins, mainly due to an identical disulfide bond pattern, stimulated us assess antimicrobial properties native, recombinant, chemically synthesized crotamine. Antimicrobial activities against standard strains clinical isolates were analyzed by colorimetric microdilution method showing weak antibacterial activity both Gram-positive Gram-negative bacteria [MIC (Minimum Inhibitory Concentration) 50->200 μg/mL], exception Micrococcus luteus ranging 1 2 μg/mL]. No detectable was observed for filamentous fungus Aspergillus fumigatus Trichophyton rubrum at concentrations up 125 μg/mL. However, pronounced antifungal Candida spp., Trichosporon Cryptococcus neoformans [12.5-50.0 μg/mL] observed. Chemically produced synthetic crotamine in general displayed MIC values similar those native crotamine, whereas recombinant overridingly more potent most assays. On other hand, derived short linear peptides not very effective apart few exceptions. Pronounced ultrastructure alteration albicans elicited electron microscopy analyses. The peculiar specificity proliferating cells confirmed here potential low cytotoxic effect nontumoral mammal cell lines (HEK293, PC12, primary culture astrocyte cells) compared tumoral B16F10 cells, no hemolytic Taken together these results suggest that, concentration, potentially valuable anti-yeast or candicidal agent, harmful effects on normal justifying further studies its mechanisms action aiming medical industrial applications.