Saccharomyces cerevisiae isolates with extreme hydrogen sulfide production showed different oxidative stress resistances responses during wine fermentation by RNA sequencing analysis

Abstract

In the wine industry, off-odors occurring during fermentation and bottling caused by hydrogen sulfide (H₂S) produced by Saccharomyces cerevisiae are still a major problem. Here, two native S. cerevisiae isolates possessing extreme H₂S production capacities were isolated from 166 strains in Chinese vineyards. Significant differences were observed in RNA sequencing analyses between the two strains. The results showed that sulfur metabolism was highly repressed and genes involved in the NADPH-dependent thioredoxin and glutaredoxin oxidoreduction systems were highly expressed in the non-H₂S producer; pathways associated with S-adenosyl methionine, and thiamine syntheses, which were related to oxidative stress resistance in yeast, were upregulated in the high H₂S producer. Oxidative stress tolerance experiment confirmed that the high H₂S producer possessed better oxidative stress tolerance, suggesting a potential connection between H₂S production and cellular stress resistance. Our findings provide insights into the differences in molecular and metabolic mechanisms between non- and high H₂S producers, highlighting the relationships between H₂S production and maintenance of the balance of oxidation potential in S. cerevisiae under wine fermentation conditions.

Keywords: H(2)S; NADPH; Oxidative stress resistance; RNA-seq.