Stress response of Saccharomyces cerevisiae to exposure to natural product pyocyanin.

Pyocyanin has been shown to engage in redox transfer of electrons from NADPH to oxygen to generate superoxide radicals. Transcriptional response to oxygen stress has been characterized in yeast and should be observable upon exposure to pyocyanin if this is the true mode of action. We used microarrays to detail the global programme of gene expression induced in the stress response to pyocyanin. Keywords: stress response Saccharomyces cerevisiae cells were exposed to 25 and 250 ug/ml of pyocyanin for a period of 6 hours incubation for RNA extraction and hybridization on Affymetrix microarrays. Results were compared to transcription levels in untreated cells under the same incubations conditions. The data indicated that transcriptional changes were consistent with an oxidative stress response, as observed by other researchers investigating the mode of action of pyocyanin toxicity.