Activities of 5-iodotubercidin against pathogenic fungi and its mode of actions

Invasive fungal infections are a tricky problem with high morbidity and mortality. The emerging of drug resistance worsens this problem. Therefore, developing novel antifungal agents is an urgent need to break these hurdles. Although protein kinase inhibitors have been extensively investigated in various fields such as cancer, diabetes, rheumatosis and so on, they are less explored in fungal infection. Previously, we found 12 protein kinase inhibitors with different antifungal activities, among them 5-iodotubercidin (5-Itu) was found to be the most potent antifungal agent with minimal inhibitory concentrations ranging from 2 to 4 μg·mL^-1. Moreover, 5-Itu displayed potent fungicidal effect, inhibition of hyphal formation and anti-biofilm activity. The mechanistic studies indicated that 5-Itu changed membrane sterol compositions and ultrastructures, increased the cell membrane permeability and induced apoptosis. Therefore, it needs to further study 5-Itu for the discovery of promising antifungal lead compounds.