Aguiar, Francisca Lidiane Linhares deSantos, Nuno C.Cavalcante, Carolina Sidrim de PaulaAndreu Martínez, DavidBaptista, Gandhi RadisGonçalves, Sónia2020-12-102020-12-102020Aguiar FLL, Santos NC, Cavalcante CSPC, Andreu D, Baptista GR, Gonçalves S. Antibiofilm activity on Candida albicans and mechanism of action on biomembrane models of the antimicrobial peptide Ctn[15-34]. Int J Mol Sci. 2020; 21(21):8339. DOI: 10.3390/ijms212183391422-0067http://hdl.handle.net/10230/45960Ctn[15-34], the C-terminal fragment of crotalicidin, an antimicrobial peptide from the South American rattlesnake Crotalus durissus terrificus venom, displays remarkable anti-infective and anti-proliferative activities. Herein, its activity on Candida albicans biofilms and its interaction with the cytoplasmic membrane of the fungal cell and with a biomembrane model in vitro was investigated. A standard C. albicans strain and a fluconazole-resistant clinical isolate were exposed to the peptide at its minimum inhibitory concentration (MIC) (10 µM) and up to 100 × MIC to inhibit biofilm formation and its eradication. A viability test using XTT and fluorescent dyes, confocal laser scanning microscopy, and atomic force microscopy (AFM) were used to observe the antibiofilm effect. To evaluate the importance of membrane composition on Ctn[15-34] activity, C. albicans protoplasts were also tested. Fluorescence assays using di-8-ANEPPS, dynamic light scattering, and zeta potential measurements using liposomes, protoplasts, and C. albicans cells indicated a direct mechanism of action that was dependent on membrane interaction and disruption. Overall, Ctn[15-34] showed to be an effective antifungal peptide, displaying antibiofilm activity and, importantly, interacting with and disrupting fungal plasma membrane.application/pdfeng© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).info:eu-repo/semantics/articlehttp://dx.doi.org/10.3390/ijms21218339Candida albicansAntimicrobial peptideBiofilmBiomembraneCrotalicidinMembrane-active peptideVenom-derived peptideYeast protoplastinfo:eu-repo/semantics/openAccess