Cu,Zn-superoxide dismutase of Saccharomyces cerevisiae is required for resistance to hyperosmosis.

Here we analyzed the role of the antioxidant response in Saccharomyces cerevisiae adaptation to hyperosmotic stress. We show that Cu,Zn-superoxide dismutase (SOD1) plays a fundamental role in this adaptation process since under hyperosmosis SOD1 mutants lead to high protein oxidation levels and show a sensitive phenotype, which is reversed by the addition of N-acetylcysteine to the medium. Pretreatment with MnCl(2), a superoxide scavenger, improves the survival of the sod1 strain upon hyperosmosis. Additionally, we show that upon hyperosmotic shock there is a small and transient increase in SOD1 transcript levels, regulated by the protein kinase A-cAMP and SKN7 pathways.