J Appl Microbiol 2018 Nov 19;125(5):1296-1307. Epub 2018 Sep 19.
Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Aims: To determine the effects of cytochalasin E, isolated from the extremophile fungus Aspergillus felis, on the cells of Paracoccidioides brasiliensis Pb18.
Methods And Results: Cytochalasin E showed a minimal inhibitory concentration of 3·6 μmol l and minimum fungicidal concentration of 7·2 μmol l on P. brasiliensis by in vitro microdilution and IC >964·0 μmol l on murine macrophages. Its selectivity index (>263) indicated that this compound has selectivity for fungal cells. Morphological alterations were determined by optical and fluorescence microscopy, as well as scanning and transmission electron microscopy. Cytochalasin E affected P. brasiliensis bud-forming pseudohyphae, cell morphology, cell walls and cell membranes; caused the release of cellular material; and resulted in the production of reactive oxygen species. In murine macrophages, it affected cytoskeletal actin and inhibited phagocytosis.
Conclusion: Cytochalasin E may be useful as an antifungal prototype against P. brasiliensis and in studies on phagocytosis.
Significance And Impact Of The Study: Paracoccidioides spp. are the etiological agents of paracoccidioidomycosis (PCM). Treatment is prolonged to control the clinical manifestations and prevent relapse. The study on the effects of cytochalasin E in P. brasiliensis is important because it can be used as a prototype for new antifungal drugs and consequently, broadens the treatment options for PCM.