Transcriptome Analysis of Saccharomyces cerevisiae and Hanseniaspora uvarum During Direct Co‐Fermentation

The ability of Hanseniaspora uvarum to improve wine quality is limited by Saccharomyces cerevisiae due to growth inhibition by S. cerevisiae. In this study, dual RNA-Seq was used to study the interaction mechanism of S. cerevisiae and H. uvarum at T1 (24 h) and T2 (72 h) during direct co-fermentation (DCF). The results indicated that H. uvarum exhibited a significant growth inhibition during DCF. The sugar consumption and ethanol production of S. cerevisiae were stronger than those of H. uvarum during single fermentation (SF). The presence of H. uvarum significantly reduced the sugar consumption and ethanol production rate of S. cerevisiae during DCF. Differentially expressed genes (DEGs) of S. cerevisiae (2152) were more than those of H. uvarum (801) during DCF. Results of transcriptomic analysis showed that carbon flux in S. cerevisiae was redirected to glycogen accumulation, whereas that of H. uvarum was redirected to trehalose metabolism. S. cerevisiae experienced oxidative stress and upregulated genes involving stress response and sulfur and amino acid metabolism. H. uvarum experienced alcohol-related stress during DCF. Additionally, different regulation of ergosterol metabolic pathway represents a key molecular mechanism underlying the dominance of S. cerevisiae. The results provide not only a theoretical basis for understanding yeast-yeast interactions but also a reference for study of other microbial interactions.