Wu Sheng, Ma Xiaoqiang, Zhou Anqi, Valenzuela Alex, Zhou Kang, Li Yanran
Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, CA 92521, USA.
Disruptive and Sustainable Technologies for Agricultural Precision, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore.
Sci Adv. 2021 Sep 17;7(38):eabh4048. doi: 10.1126/sciadv.abh4048.
Strigolactones (SLs) are a class of phytohormones playing diverse roles in plant growth and development, yet the limited access to SLs is largely impeding SL-based foundational investigations and applications. Here, we developed – consortia to establish a microbial biosynthetic platform for the synthesis of various SLs, including carlactone, carlactonoic acid, 5-deoxystrigol (5DS; 6.65 ± 1.71 μg/liter), 4-deoxyorobanchol (3.46 ± 0.28 μg/liter), and orobanchol (OB; 19.36 ± 5.20 μg/liter). The SL-producing platform enabled us to conduct functional identification of CYP722Cs from various plants as either OB or 5DS synthase. It also allowed us to quantitatively compare known variants of plant SL biosynthetic enzymes in the microbial system. The titer of 5DS was further enhanced through pathway engineering to 47.3 μg/liter. This work provides a unique platform for investigating SL biosynthesis and evolution and lays the foundation for developing SL microbial production process.
独脚金内酯（SLs）是一类在植物生长发育中发挥多种作用的植物激素，但获取SLs的途径有限，这在很大程度上阻碍了基于SLs的基础研究和应用。在此，我们组建了联合体，以建立一个用于合成多种SLs的微生物生物合成平台，这些SLs包括独脚金烯、独脚金烯酸、5-脱氧独脚金醇（5DS；6.65±1.71微克/升）、4-脱氧菜豆素（3.46±0.28微克/升）和菜豆素（OB；19.36±5.20微克/升）。该产生SLs的平台使我们能够对来自不同植物的CYP722Cs作为OB或5DS合酶进行功能鉴定。它还使我们能够在微生物系统中对植物SL生物合成酶的已知变体进行定量比较。通过途径工程，5DS的产量进一步提高到47.3微克/升。这项工作为研究SL生物合成和进化提供了一个独特的平台，并为开发SL微生物生产工艺奠定了基础。
