Elevated Vacuolar Uptake of Fluorescently Labeled Antifungal Drug Caspofungin Predicts Echinocandin Resistance in Pathogenic Yeast.

Autor:	Jaber QZ; School of Chemistry, Raymond & Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel., Bibi M; School of Molecular Cell Biology and Biotechnology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel., Ksiezopolska E; Barcelona Supercomputing Centre (BSC-CNS) Jordi Girona, 29, Barcelona 08034, Spain.; Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, Barcelona 08028, Spain., Gabaldon T; Barcelona Supercomputing Centre (BSC-CNS) Jordi Girona, 29, Barcelona 08034, Spain.; Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, Barcelona 08028, Spain.; Catalan Institution for Research and Advanced Studies, Passeig de Lluís Companys, 23, Barcelona 08010, Spain., Berman J; School of Molecular Cell Biology and Biotechnology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel., Fridman M; School of Chemistry, Raymond & Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
Jazyk:	angličtina
Zdroj:	ACS central science [ACS Cent Sci] 2020 Oct 28; Vol. 6 (10), pp. 1698-1712. Date of Electronic Publication: 2020 Sep 09.
DOI:	10.1021/acscentsci.0c00813
Abstrakt:	Echinocandins are the newest class of antifungal drugs in clinical use. These agents inhibit β-glucan synthase, which catalyzes the synthesis of β-glucan, an essential component of the fungal cell wall, and have a high clinical efficacy and low toxicity. Echinocandin resistance is largely due to mutations in the gene encoding β-glucan synthase, but the mode of action is not fully understood. We developed fluorescent probes based on caspofungin, the first clinically approved echinocandin, and studied their cellular biology in Candida species, the most common cause of human fungal infections worldwide. Fluorescently labeled caspofungin probes, like the unlabeled drug, were most effective against metabolically active cells. The probes rapidly accumulated in Candida vacuoles, as shown by colocalization with vacuolar proteins and vacuole-specific stains. The uptake of fluorescent caspofungin is facilitated by endocytosis: The labeled drug formed vesicles similar to fluorescently labeled endocytic vesicles, the vacuolar accumulation of fluorescent caspofungin was energy-dependent, and inhibitors of endocytosis reduced its uptake. In a panel comprised of isogenic Candida strains carrying different β-glucan synthase mutations as well as clinical isolates, resistance correlated with increased fluorescent drug uptake into vacuoles. Fluorescent drug uptake also associated with elevated levels of chitin, a sugar polymer that increases cell-wall rigidity. Monitoring the intracellular uptake of fluorescent caspofungin provides a rapid and simple assay that can enable the prediction of echinocandin resistance, which is useful for research applications as well as for selecting the appropriate drugs for treatments of invasive fungal infections. Competing Interests: The authors declare no competing financial interest.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu