Multi-omics framework reveals molecular determinants of small peptide trileucine enhancing ethanol stress tolerance in industrial yeast.

Ethanol stress is a major limiting factor affecting yeast performance and ethanol yield in alcoholic beverages and bioethanol industrial fermentation. This study revealed that wheat gluten peptide trileucine supplementation enhanced the ethanol stress tolerance of yeast by maintaining cell structural integrity, regulating amino acid metabolism and increasing energy supply. Following trileucine supplementation, 288 differential metabolites (DMs) and 1090 differentially expressed genes (DEGs) were identified. By integrating transcriptomic and metabolomic datasets, a global molecular regulatory network of trileucine-mediated yeast ethanol tolerance was constructed. Using this dataset, key functional genes, such as LYS1, AAT2, ARG1, GND1, and ERG10, were identified and validated, and overexpression of these genes enhanced yeast tolerance to ethanol stress. These findings elucidate the global molecular regulatory mechanism by which small peptide trileucine enhances ethanol tolerance in yeast, and provide valuable resources for future stress tolerance improvement and molecular design of yeast.