Identification of Core Regulatory Genes and Metabolic Pathways for the -Propanol Synthesis in .

The -propanol produced by has a remarkable effect on the taste and flavor of Chinese Baijiu. The -propanol metabolism-related genes were deleted to evaluate the role in the synthesis of -propanol to ascertain the key genes and pathways for the production of -propanol by . The results showed that 3, 1, 6, 1, 5, and 082 were the key genes affecting the -propanol metabolism in yeast. The -propanol concentrations of α5Δ1, α5Δ3, and α5Δ6 increased by 121.75, 22.75, and 17.78%, respectively, compared with α5. The -propanol content of α5Δ1, α5Δ5, and α5Δ082 decreased by 24.98, 8.35, and 8.44%, respectively, compared with α5. The contents of intermediate metabolites were measured, and results showed that the mutual transformation of glycine and threonine in the threonine pathway and the formation of propanal from 2-ketobutyrate were the core pathways for the formation of -propanol. Additionally, 082 played important role in the synthesis of -propanol by directly producing 2-ketobutyric acid through l-homoserine. This study provided valuable insights into the -propanol synthesis in and the theoretical basis for future optimization of yeast strains in Baijiu making.