Improvement of 2-phenylethanol production by deleting gene PDC5 and related metabolic strategies in Saccharomyces cerevisiae
ZHU Linghuan1,2,3, XU Sha1,2, LI Youran1,2, ZHANG Liang1,2, SHI Guiyang1,2*
1(School of Biotechnology, Jiangnan University, Wuxi 214122, China) 2(National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China) 3(College of Food Science and Biology, Hebei University of Science and Technology, Shijiazhuang 050018, China)
Abstract: As an important aromatic alcohols with favorable flavor and superior property, 2-phenylethanol has been widely used in food, medicine, and chemical industry. In this study, the deletion of phenylpyruvate decarboxylase gene PDC5 was found to improve the synthesis of 2-phenylethanol, and related metabolic strategy of the Ehrlich pathway was rational reconstructed in Saccharomyces cerevisiae for further product-enhancement. Strain RM22 (pdc5△) was obtained using CRISPR/Cas9, and improved 2-phenylethanol production was observed in the optimized culture conditions. Additionally, by expressing aromatic transaminase Aro8p and Aro9p respectively, we found that overexpressing of Aro8p in aro9-deleted strain was an efficient strategy to increase 2-phenylethanol production. To further improve the production of 2-phenylethanol, metabolic engineered strain RM-59810 (pdc5△aro9△PTPI-ARO8-TTT PTPI-ARO10-TTT) was constructed, resulting in 3.85 g/L of 2-phenylethanol from 6.7 g/L phenylalanine after 120 h, and the molar conversion rate was 0.67 mol/mol, which was 1.33-fold than that of the control strain, with a yield of 0.5 g/g L-phenylalanine. In this study, a new efficient strategy was provided to improve 2-phenylethanol production in S. cerevisiae, and also provided a primary foundation for studying the possible regulatory effects of pyruvate decarboxylase Pdc5p.
朱灵桓,徐沙,李由然,等. 酿酒酵母PDC5基因的缺失对2-苯乙醇合成的影响及相关代谢改造[J]. 食品与发酵工业, 2021, 47(16): 22-30.
ZHU Linghuan,XU Sha,LI Youran,et al. Improvement of 2-phenylethanol production by deleting gene PDC5 and related metabolic strategies in Saccharomyces cerevisiae[J]. Food and Fermentation Industries, 2021, 47(16): 22-30.
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