Response of Saccharomyces cerevisiae (Dal80Δ) to linoleic acid hydroperoxide

Oxidative stress is experienced by all aerobic organisms and results in cellular damage. The damage caused during oxidative stress is particular to the oxidant challenge faced, and so too is the induced stress response. The eukaryote Saccharomyces cerevisiae is sensitive to low concentrations of the lipid hydroperoxide - linoleic acid hydroperoxide (LoaOOH) - and its response is unique relative to other peroxide treatments. Part of the yeast response to LoaOOH includes a change in the cellular requirement for nutrients, such as sulfur, nitrogen and various metal ions. The metabolism of sulfur is involved in antioxidant defence, although the role nitrogen during oxidative stress is not well understood. Investigating the response induced by yeast to overcome LoaOOH exposure, with a particular focus on nitrogen metabolism, will lead to greater understanding of how eukaryotes survive lipid hydroperoxide-induced stress, and associated lipid peroxidation, which occurs in the presence of polyunsaturated fatty acids. We used genome-wide microarrays to investigate the changes in gene expression of S. cerevisiae (Dal80Δ) to LoaOOH-induced oxidative stress. S. cerevisiae (Dal80Δ) were exposed to an arresting concentration of LoaOOH (75 µM) for 1 hr to induce oxidative stress. Yeast treated with an equivalent volume of solvent (methanol) were used as a control. Following treatment conditions, total RNA was extracted from LoaOOH-treated or control yeast and hybridised onto Affymetrix microarrays.