A great number of recent reports seem to confirm the
Harman “free radical theory of ageing” [11] proposed some 50 years
ago notwithstanding the many still remaining unknown details. In our
previous study, a proteomic approach was used to evaluate the redox
state of yeast protein cysteines during chronological ageing [12]. We
demonstrated that glucose restriction and growth on glycerol
supplemented media extend S. cerevisiae lifespan and that oxidative
damage in cells grown on high glucose mostly affects glycolytic
enzymes. Studying how yeast adapts to environmental changes is
important, for the optimization of its industrial applications and also
because knowledge gained during such experiments could help
understand some important eukaryotic cells biological processes.
Comprehensive transcriptome analyses have been performed to study
the effects of different nutrient conditions on yeast [13–16]. These
genome-wide expression profiles show how they respond to different
nutritional environments at transcriptional level. However, increasing
evidence shows that mRNA abundance is not always correlated with
protein expression levels [17–21]. Therefore, it is essential to study
yeast adaptation and other biological processes with proteome
studies, that allow the analysis of all proteins present in a certain
condition. Two-dimensional reference maps have been constructed
for important industrial yeast strains [22–25]. Many quantitative 2Dgel-
based studies analyzed yeast growth under different environmental
conditions [26–28]. We performed a proteomic study to
understand how S. cerevisiae adapts its metabolism during the
exponential growth in medium supplemented with three different
concentrations of glucose: 2%, 0.5% and 20%. A medium with 20%
glucose concentration is very similar to natural must.