Nanoscale effects of Caspofungin against two yeast species; Saccharomyces cerevisiae and Candida albicans.
Antimicrob Agents Chemother. 2013 May 13;
Authors: Formosa C, Schiavone M, Martin-Yken H, François JM, Duval RE, Dague E
Saccharomyces cerevisiae and Candida albicans are model yeasts for biotechnology and human health, respectively. We used Atomic Force Microscopy to explore the effects of caspofungin, an antifungal drug used in hospitals, on these two species. Our nanoscale investigation revealed similar but also different behavior of the two yeasts in response to the treatment with this drug. While administration of caspofungin induced a deep cell wall remodeling in both yeast species, as witnessed by a dramatic increase of chitin and decrease in β-glucan content, changes in cell wall composition were more pronounced with Candida albicans cells. Notably, the increase of chitin was proportional to the increase in the caspofungin dose. In addition, the Young modulus of the cell was three times lower for C. albicans cells than for S. cerevisiae cells, and increased proportionally with the increase of chitin, suggesting differences in the molecular organization of the cell wall between these two yeast species. Also, at low dose of caspofungin (i.e. 0.5×MIC), the cell surface of C. albicans exhibited a morphology that was reminiscent to cells expressing adhesion proteins. Interestingly, this morphology was lost at high dose of the drug (i.e. 4×MIC). However, the treatment of S. cerevisiae cell with high doses of caspofungin resulted in an impairment of cytokinesis. Altogether, the use of AFM for investigating the effect of antifungal drug is relevant in nanomedicine, as it should help understanding their mechanism of action on the fungal cells, as well as unraveling unexpected effects on cell division and fungal adhesion.
PMID: 23669379 [PubMed - as supplied by publisher]