Phenotypic and genomic differences among S. cerevisiae strains in nitrogen requirements during wine fermentations

Nitrogen requirements by S. cerevisiae during wine fermentation are highly strain-dependent. Different approaches were applied to explore the nitrogen of 28 yeast strains. Based on growth and behaviour displayed at different concentrations, high low nitrogen-demanding strains selected further verified competition fermentation. Biomass production with increasing concentrations in exponential phase was analysed chemostat cultures. Low (LND) produced a larger amount biomass nitrogen-limited synthetic grape musts, whereas (HND) achieved bigger yield when YAN concentration above 100 mg/L. Constant rate carried out both determine required maintain highest rate. Large differences appeared analysis genomes high-nitrogen demanding showed for heterozygosity amino acid substitutions between orthologous proteins, recycling system genes showing widest divergences. The CRISPR/Cas9-mediated genome modification method used validate involvement GCN1 strain needs. However, allele swapping gene from did not significantly influence