Drug development is a dynamic field which undergoes changes continuously. The past decade or so has witnessed huge strides in the field of screening of the drugs as well as target and ligand identifications but unfortunately this has not led to useful drugs. Many diseases still remain untreatable because we do not have proper drugs against them. In case of fungi the situation is graver due to the limited drug targets peculiar to fungi. Thus, in order to combat the fungal diseases the need of the hour is to develop new antifungals that have fewer side effects and broad spectrum activity.
The current work deals with closantel, a veterinary drug targeting chitinase, which is utilized as a therapeutic option against helminths. The fact that chitin is an important constituent of the cell wall of the fungi also and it undergoes regular degradation and remodelling through an enzyme called fungal chitinase motivated the authors to test the efficacy of closantel against fungal chitinase. In the present study Cryptococcus neoformans has been used as a model organism against which the antifungal activity of closantel has been tested.
In-silico studies carried out using PatchDock and FireDock predicted the global energy (binding energy)involved in docking closantel on chitinase as -47.58 Kcal/mol. Further, the results obtained through the in-silico studies were validated by the minimum inhibitory concentration assay (MIC). It was observed that 736 (±7.024) µg/ml of closantel can inhibit the cryptococcal growth by 80% (MIC80).