Antibiofilm activity on Candida albicans and mechanism of action on biomembrane models of the antimicrobial peptide Ctn[15-34]

Ctn[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 c...

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Bibliographic Details
Authors: Aguiar, Francisca Lidiane Linhares de, Santos, Nuno C., Cavalcante, Carolina Sidrim de Paula, Andreu Martínez, David, Baptista, Gandhi Radis, Gonçalves, Sónia
Format: article
Status:Published version
Publication Date:2020
Country:España
Institution:Universitat Pompeu Fabra
Repository:Repositorio Digital de la UPF
OAI Identifier:oai:repositori.upf.edu:10230/45960
Online Access:http://hdl.handle.net/10230/45960
http://dx.doi.org/10.3390/ijms21218339
Access Level:Open access
Keyword:Candida albicans
Antimicrobial peptide
Biofilm
Biomembrane
Crotalicidin
Membrane-active peptide
Venom-derived peptide
Yeast protoplast
Description
Summary:Ctn[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.