Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100193, China.
Engineering Research Center of Chinese Medicine Resource, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100193, China.
ACS Synth Biol. 2020 May 15;9(5):1160-1168. doi: 10.1021/acssynbio.0c00039. Epub 2020 Apr 7.
Crocins are highly valuable medicinal compounds for treating human disorders, and they also serve as spices and coloring agents. However, the supply of crocins from plant extractions is insufficient for current demands, and using synthetic biology to produce crocins remains a big challenge. Here, we report the production of five types of crocins in with GjUGT94E13 and GjUGT74F8, which are responsible for the glycosylation of crocetin, from the crocin-producing plant . Subsequently, native UDP-glucose biosynthesis in is strengthened by the overexpression of and . The optimization of catalytic reactions has demonstrated that 50 mM NaHPO-NaHPO buffer (pH 8.0) plus 5% glucose is the best medium to use for the efficient glycosylation of crocetin. In engineered , the conversion rate of crocin III and crocin V from crocetin (50 mg/L) by the catalysis of GjUGT74F8 was increased to 66.1%, and the conversion rate of five types of crocins from crocetin (50 mg/L) via GjUGT94E13 and GjUGT74F8 was 59.6%, much higher than the catalytic activity of the reported microbial UGTs. This study not only sheds light on the biosynthesis of crocins in , but also provides important genetic tools for the synthesis of crocins.
西红花苷是一种极具药用价值的化合物，可用于治疗人类疾病，同时也可用作香料和着色剂。然而，从植物提取的西红花苷供应无法满足当前的需求，因此利用合成生物学生产西红花苷仍然是一个巨大的挑战。在这里，我们报告了在 中利用负责 crocetin 糖基化的 GjUGT94E13 和 GjUGT74F8 生产 5 种西红花苷的情况，这两种酶来自产西红花苷植物 。随后，通过过表达 和 来增强 中的天然 UDP-葡萄糖生物合成。催化反应的优化表明，在 50 mM NaHPO-NaHPO 缓冲液（pH 8.0）加 5%葡萄糖的最佳介质中，西红花苷的糖基化效率最高。在工程化的 中，GjUGT74F8 催化 crocetin（50 mg/L）生成 crocin III 和 crocin V 的转化率提高到 66.1%，而通过 GjUGT94E13 和 GjUGT74F8 从 crocetin（50 mg/L）生成 5 种西红花苷的转化率为 59.6%，明显高于已报道的微生物 UGT 的催化活性。本研究不仅阐明了 中西红花苷的生物合成途径，还为西红花苷的 合成提供了重要的遗传工具。
