Induction of Hsp104 by Cr(VI) in yeast Candida intermedia

The synthesis of a polypeptide family named heat shock or stress proteins is one of the most conserved mechanisms of cellular protection in the case of changes in the environment. Among them Hsp104 is important, because it promotes survival of cells under extreme stresses such as high temperatures, severe oxidative damage and high concentrations of ethanol. The aim of our research was to investigate whether Hsp104 is induced in the yeast Candida intermedia exposed to Cr(VI). Namely, Cr(VI) belongs to redox active metals, which play an important role in the generation of reactive oxygen species in the cell and therefore they can lead to oxidative damages. Yeast cells were treated with Cr(VI) in the midexponential phase and after a defined time of incubation, Hsp104 induction was investigated by using Western blotting. Results showed that cultivation of yeast cells in the presence of 100 μM Cr(VI) caused induction of Hsp104, which is connected to formation of protein aggregates. Hsp104 assists their resolubilization and so contributes to cell survival. Its synthesis was detected 0.5 h after Cr(VI) addition and was later for up to 2 h more apparent. Therefore, we showed that Hsp104 plays an important role in the stress response of yeast Candida intermedia to Cr(VI).