Liu Tengfei, Dong Chang, Qi Mingming, Zhang Bei, Huang Lei, Xu Zhinan, Lian Jiazhang
Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China.
Center for Synthetic Biology, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China.
Front Bioeng Biotechnol. 2020 Jun 30;8:653. doi: 10.3389/fbioe.2020.00653. eCollection 2020.
Crocetin is a plant natural product with broad medicinal applications, such as improvement of sleep quality and attenuation of physical fatigue. However, crocetin production using microbial cell factories is still far from satisfaction, probably due to the conflict between cell growth and product accumulation. In the present work, a temperature-responsive crocetin-producing strain was established to coordinate cell growth, precursor (zeaxanthin) generation, and product (crocetin) biosynthesis. The production of crocetin was further enhanced via increasing the copy numbers of and genes using the CRISPR-Cas9 based multiplex genome integration technology. The final engineered strain TL009 produced crocetin up to 139.67 ± 2.24 μg/g DCW. The advantage of the temperature switch based crocetin production was particularly demonstrated by much higher zeaxanthin conversion yield. This study highlights the potential of the temperature-responsive yeast platform strains to increase the production of other valuable carotenoid derivatives.
西红花酸是一种具有广泛医学应用的植物天然产物，如改善睡眠质量和减轻身体疲劳。然而，利用微生物细胞工厂生产西红花酸仍远不能令人满意，这可能是由于细胞生长与产物积累之间的矛盾所致。在本研究中，构建了一种温度响应型西红花酸生产菌株，以协调细胞生长、前体（玉米黄质）生成和产物（西红花酸）生物合成。利用基于CRISPR-Cas9的多重基因组整合技术增加 和 基因的拷贝数，进一步提高了西红花酸的产量。最终构建的工程菌株TL009产生的西红花酸高达139.67±2.24μg/g干细胞重。基于温度切换的西红花酸生产的优势尤其体现在更高的玉米黄质转化率上。本研究突出了温度响应型酵母平台菌株在提高其他有价值类胡萝卜素衍生物产量方面的潜力。
