Role of glutathione in ethanol stress tolerance in yeast Pachysolen tannophilus.

The effect of glutathione enrichment and depletion on the survival of Pachysolen tannophilus after ethanol stress was investigated. In this work, we verified that both control and glutathione deficient yeast cells were much more oxidized after ethanol stress. Depletion of cellular glutathione enhanced the sensitivity to ethanol and suppressed the adaptation. Incubation of the cell with amino acids constituting glutathione (GIu, Cys, Gly) increased the intracellular glutathione content, and subsequently the cell acquired resistance against ethanol. The level of reactive oxygen species, protein carbonyl, and lipid peroxidation in glutathione enriched groups were also studied. These results strongly suggest that intracellular glutathione plays an important role in the adaptive response in P. tannophilus to ethanol induced oxidative stress.