A Novel Role of Fungal Type I Myosin in Regulating Membrane Properties and Its Association with d -Amino Acid Utilization in Cryptococcus gattii

Abstract

Cryptococcus gattii , one of the etiological agents of cryptococcosis, can be distinguished from its sister species Cryptococcus neoformans by growth on d -amino acids. C. gattii MYO5 affected the growth of C. gattii on d -amino acids. The myo5Δ cells accumulated high levels of various substrates from outside the cells, and excessively accumulated d -amino acids appeared to have caused toxicity in the myo5Δ cells. We provide evidence on the alteration of membrane properties in the myo5Δ mutants. Additionally, alteration in the myo5Δ membrane permeability causing higher substrate accumulation is associated with the changes in the sterol distribution. Furthermore, myosin-I in three other yeasts also manifested a similar role in substrate accumulation. Thus, while fungal myosin-I may function as a classical myosin-I, it has hitherto unknown additional roles in regulating membrane permeability. Since deletion of fungal myosin-I causes significantly elevated susceptibility to multiple antifungal drugs, it could serve as an effective target for augmentation of fungal therapy.