Efficient production of glycyrrhetinic acid in metabolically engineered Saccharomyces cerevisiae via an integrated strategy

作者：Caixia Wang, Xinyao Su, Mengchu Sun, Mengting Zhang, Jiajia Wu, Jianmin Xing, Ying Wang, Jianping Xue, Xia Liu, Wei Sun, Shilin Chen · 发表于：Microbial Cell Factories · 年份：2019 · DOI：10.1186/s12934-019-1138-5 · 被引用次数：64 · 研究领域：Pharmacological Effects of Natural Compounds、Plant biochemistry and biosynthesis、Hormonal Regulation and Hypertension

BACKGROUND: Glycyrrhetinic acid (GA) is the most important ingredient in licorice due to its outstanding anti-inflammatory activity and wide application in the medicine and cosmetics industries. Contemporary industrial production of GA by acid hydrolysis of glycyrrhizin which was extracted from Glycyrrhiza plants, is not environment-friendly and devastates farmland since the Glycyrrhiza rhizomes grow up to 10 m underground. RESULTS: In this study, GA was produced through metabolically engineering Saccharomyces cerevisiae by introducing the entire heterogeneous biosynthetic pathway of GA. Codon optimized CYP88D6 and CYP72A154, combined with β-AS (β-amyrin synthase encoding gene) and the NADPH-cytochrome P450 reductase gene of Arabidopsis thaliana were introduced into S. cerevisiae. The resulting strain (Y1) produced 2.5 mg/L of β-amyrin and 14 μg/L of GA. The cytochrome b5 from G. uralensis (GuCYB5) was identified and the introduction of this novel GuCYB5 increased the efficiency of GA production by eightfold. The joint utilization of the GuCYB5 gene along with 10 known MVA pathway genes from S. cerevisiae were overexpressed in a stable chromosome integration to achieve higher GA production. Using the combined strategy, GA concentration improved by 40-fold during batch fermentation. The production was further improved to 8.78 mg/L in fed-batch fermentation, which was increased by a factor of nearly 630. CONCLUSIONS: This study first investigated the influence of carbon flux in...