Transcriptomic and proteomic effects of (-)-epigallocatechin 3-O-(3-O-methyl) gallate (EGCG3"Me) treatment on ethanol-stressed Saccharomyces cerevisiae cells.

Saccharomyces cerevisiae (S. cerevisiae) is the main fermentation strain in brewing industry. However, the accumulation of ethanol during the fermentation inhibits the growth of S. cerevisiae. Polyphenols are important bioactive ingredients in oolong tea, and epigallocatechin-3-O-(3"-O-methyl)-gallate (EGCG3"Me) has exhibited ameliorate effect on alcohol intoxication. Therefore, in the current work, we used RNA-seq transcriptomics and iTRAQ proteomic analysis to study the effect of EGCG3"Me on ethanol-stressed S. cerevisiae. After EGCG3"Me intervention (0.8%, w/v), 178 up-regulated and 172 down-regulated genes were identified, meanwhile, 190 differentially expressed proteins (DEPs) were identified. In addition, KEGG pathways for metabolic pathways, biosynthesis of secondary metabolites and microbial metabolism were among the most DEPs after EGCG3"Me intervention. The integrated transcriptomic and proteomic analysis indicated EGCG3"Me may alleviate ethanol-induced damage on the cell wall and cell membrane of S. cerevisiae, and facilitate the redox balance and glycolysis. This study provides new insights into the mechanisms underlying the molecular response to ethanol in S. cerevisiae by the treatment of EGCG3"Me.