18 research outputs found
Phenotypic Landscape of Saccharomyces cerevisiae during Wine Fermentation: Evidence for Origin-Dependent Metabolic Traits
The species Saccharomyces cerevisiae includes natural strains, clinical isolates, and a large number of strains used in human activities. The aim of this work was to investigate how the adaptation to a broad range of ecological niches may have selectively shaped the yeast metabolic network to generate specific phenotypes. Using 72 S. cerevisiae strains collected from various sources, we provide, for the first time, a population-scale picture of the fermentative metabolic traits found in the S. cerevisiae species under wine making conditions. Considerable phenotypic variation was found suggesting that this yeast employs diverse metabolic strategies to face environmental constraints. Several groups of strains can be distinguished from the entire population on the basis of specific traits. Strains accustomed to growing in the presence of high sugar concentrations, such as wine yeasts and strains obtained from fruits, were able to achieve fermentation, whereas natural yeasts isolated from “poor-sugar” environments, such as oak trees or plants, were not. Commercial wine yeasts clearly appeared as a subset of vineyard isolates, and were mainly differentiated by their fermentative performances as well as their low acetate production. Overall, the emergence of the origin-dependent properties of the strains provides evidence for a phenotypic evolution driven by environmental constraints and/or human selection within S. cerevisiae
Nitrogen demand of different yeast strains during alcoholic fermentation. Importance of the stationary phase
International audienc
Use of constant rate alcoholic fermentations to compare the effectiveness of different nitrogen sources added during the stationary phase
International audienc
Regulation of alcoholic fermentation rate by assimilable nitrogen addition. Comparison of different nitrogen sources
National audienc
Effectivness of combined ammoniacal nitrogen and oxygen additions for completion of sluggish and stuck wine fermentations
International audienc
Effect of variety, year, and grape maturity on the kinetics of alcoholic fermentation
International audienc