Transcriptome Analysis of a Wine Yeast Strain with a Deletion of the CAR1 Arginase Gene

Abstract—

Ethyl carbamate, a potential carcinogen, is formed in wine as a result of a chemical reaction between ethanol and urea during fermentation and storage. Using genome editing methods, a modified strain of wine yeast Saccharomyces cerevisiae was constructed, with a deletion of the CAR1 arginase gene, leading to a decrease in the formation of urea from arginine. Transcriptome analysis by high-throughput sequencing identified 738 genes whose transcription level reliably changed more than twofold as a result of deletion of the CAR1 gene. Expression of most genes of the central metabolic pathways in the CAR1 deletion strain was decreased; increased transcription levels were observed for the Map kinase signaling cascades. Among the genes of arginine metabolism pathways, the level of transcription of the ornithine aminotransferase gene CAR2 increased significantly. The wine material obtained using a strain with a deletion of the CAR1 gene under micro-winemaking conditions contained 25% less urea than in the case of using an unmodified strain. The resulting strain of wine yeast, having lower urea levels, may be promising for winemaking.