Variations in nitrogen consumption between Saccharomyces cerevisiae strains reflect different adaptation strategies to face changes in nitrogen availability

Saccharomyces cerevisiae strains present a wide genetic diversity, largely as a result of human efforts to develop strains specifically adapted to various fermentation processes. These adaptive pressures in various ecological niches have generated behavioral differences among these strains, particularly in terms of nitrogen assimilation capacity. In this work, we characterize this latter phenotype, during oenological fermentation conditions, using a new approach. Indeed, unlike previous studies, we worked in an environment with excess nitrogen, eliminating the nitrogen limitation/starvation factor that is generally observed in fermentation processes. Using these conditions, we evaluated differences in both nitrogen assimilation capacity and nitrogen compound preference for a set of five strains from heterogeneous origins. We report that these strains can be classified as high nitrogen consuming (HNC) or low nitrogen consuming (LNC) and that their differences seem to be correlated with the nitrogen uptake rate and variations in nitrogen sensing and signaling among strains. Furthermore, these differences in nitrogen assimilation capacity are associated with differences in cellular stress status and fermentation performance, which likely reflects different strain adaptation patterns to fermenting environments.

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