Fungicidal effect of antimicrobial peptide arenicin-1.

Arenicin-1 is a 21-residue peptide which was derived from Arenicola marina. In this study, we investigated the antifungal effects and its mechanism of action towards human pathogenic fungi. Arenicin-1 exerted remarkable fungicidal activity with both energy-dependent and salt-insensitive manners. To investigate the fungicidal mechanisms of arenicin-1, the membrane interactions of arenicin-1 were examined. Flow cytometric analysis, using propidium iodide (PI) and bis-(1,3-dibutylbarbituric acid) trimethine oxonol [DiBAC(4)(3)], as well as fluorescence analysis, regarding the membrane probe 1,6-diphenyl-1,3,5-hexatriene (DPH), were conducted against Candida albicans. The results demonstrated that arenicin-1 was associated with lipid bilayers and induced membrane permeabilization. Additionally, the membrane studies in regard to liposomes resembling the phospholipid bilayer of C. albicans confirmed the membrane-disruptive potency of arenicin-1. Therefore, the present study suggests that arenicin-1 exerts its fungicidal effect by disrupting fungal phospholipid membranes.