BioProject

Laboratory strains of Saccharmoyces cerevisiae have been widely used as a model for studying eukaryotic cells and mapping the molecular mechanisms of many different human diseases. More...

Laboratory strains of Saccharmoyces cerevisiae have been widely used as a model for studying eukaryotic cells and mapping the molecular mechanisms of many different human diseases. Industrial wine yeasts, on the other hand, have been selected over hundreds of years on the basis of their adaptation to stringent environmental conditions and the organoleptic properties they confer to wine. Here, we applied a two-factor design to study the response of a standard laboratory strain, CEN.PK.113-7D, and an industrial wine yeast-strain, EC1118, to growth temperature at 15°C and 30°C under 12 nitrogen-limited, anaerobic steady-state chemostat cultures. Physiological characterization revealed that growth temperature strongly impacted biomass yields in both strains. Moreover, we observed that the wine yeast is better adapted to mobilizing resources for biomass and that the laboratory yeast exhibited higher fermentation rates. To elucidate mechanistic differences controlling the growth temperature response and underlying adaptive mechanisms between strains, DNA microarrays and targeted metabolome analysis were used. We identified 1007 temperature dependent genes and 473 strain dependent genes. The transcriptional response was used to identify highly correlated subnetworks of significantly changing genes in metabolism. We show that temperature differences most strongly affect nitrogen metabolism and the heat shock response. Lack of STRE mediated gene induction, coupled with reduced trehalose levels, indicates a decreased general stress response at 15°C relative to 30°C. Between strains, differential responses are centred around sugar uptake, nitrogen metabolism and expression of genes related to organoleptic properties. Our study provides global insight into how growth temperature exerts a differential physiological and transcriptional response in laboratory and wine strains of S. cerevisiae. Overall design: We used a two-factor design with two S.cerevisiae strains, grown at two temperatures (ab strain: CEN.PK 113-7D and Industrial Wine strain EC1118, 15ºC and 30ºC, respectively) in anaerobic continuous cultures (D=0.05) in biological triplicates. Less...