Effects of the Natural Peptide Crotamine from a South American Rattlesnake on <i>Candida auris</i>, an Emergent Multidrug Antifungal Resistant Human Pathogen

• Main Authors: Caroline Dal Mas, Luana Rossato, Thaís Shimizu, Eduardo B. Oliveira, Pedro I. da Silva Junior, Jacques F. Meis, Arnaldo Lopes Colombo, Mirian A. F. Hayashi
• Format: Article
• Language: English
• Published: MDPI AG 2019-05-01
• Series: Biomolecules
• Subjects: rattlesnake venom toxin; crotamine; antimicrobial peptide; multiresistant strain; fungus; <i>Candida</i> spp.
• Online Access: https://www.mdpi.com/2218-273X/9/6/205

Invasive <i>Candida</i> infections are an important growing medical concern and treatment options are limited to a few antifungal drug classes, with limited efficacies depending on the infecting organism. In this scenario, invasive infections caused by multiresistant <i>Candida auris</i> are emerging in several places around the world as important healthcare-associated infections. As antimicrobial peptides (AMPs) exert their activities primarily through mechanisms involving membrane disruption, they have a lower chance of inducing drug resistance than general chemical antimicrobials. Interestingly, we previously described the potent candicidal effect of a rattlesnake AMP, crotamine, against standard and treatment-resistant clinical isolates, with no hemolytic activity. We evaluated the antifungal susceptibility of several <i>Candida</i> spp. strains cultured from different patients by using the Clinical and Laboratory Standards Institute (CLSI) microdilution assay, and the antifungal activity of native crotamine was evaluated by a microbial growth inhibition microdilution assay. Although all <i>Candida</i> isolates evaluated here showed resistance to amphotericin B and fluconazole, crotamine (40&#8722;80 &#181;M) exhibited in vitro activity against most isolates tested. We suggest that this native polypeptide from the South American rattlesnake <i>Crotalus durissus terrificus</i> has potential as a structural model for the generation of a new class of antimicrobial compounds with the power to fight against multiresistant <i>Candida</i> spp.