Longping Branch, College of Biology, Hunan University, Changsha 410125, China.
Agriculture Product Processing Institute, Hunan Academy of Agricultural Sciences, Changsha 410125, China.
ACS Synth Biol. 2023 Sep 15;12(9):2740-2749. doi: 10.1021/acssynbio.3c00348. Epub 2023 Aug 11.
Flavonoids are an essential class of secondary metabolites found in plants and possess various nutritional, medicinal, and agricultural properties. However, the poor water solubility of flavonoid aglycones limits their potential applications. To overcome this issue, glycosylation is a promising approach for improving water solubility and bioavailability. In this study, we constructed a flavonoid-7--disaccharide biosynthetic pathway with flavonoid aglycones as substrates in . Subsequently, through metabolic engineering and promoter strategies, we constructed a UDP-rhamnose regeneration system and optimized the UDP-glucose (UDPG) synthetic pathway. The optimized strain produced up to 131.3 mg/L eriocitrin. After this, the chassis cells were applied to other flavonoids, with substrates such as (2)-naringenin, (2)-hesperetin, diosmetin, and (2)-eriodictyol, which resulted in the synthesis of 179.9 mg/L naringin, 276.6 mg/L hesperidin, 249.0 mg/L neohesperidin, 30.4 mg/L diosmin, and 100.7 mg/L neoeriocitrin. To the best of our knowledge, this is the first report on the biosynthesis of flavonoid-7--disaccharide.
类黄酮是植物中一类重要的次生代谢产物，具有多种营养、药用和农业特性。然而，类黄酮苷元的水溶性差限制了它们的潜在应用。为了解决这个问题，糖基化是提高水溶性和生物利用度的一种很有前途的方法。在本研究中，我们以类黄酮苷元为底物，在 中构建了一个类黄酮-7--二糖生物合成途径。随后，通过代谢工程和启动子策略，我们构建了一个 UDP-鼠李糖再生系统，并优化了 UDP-葡萄糖（UDPG）合成途径。优化后的菌株可产生高达 131.3 mg/L 的圣草酚。之后，底盘细胞被应用于其他类黄酮，以（2）-柚皮素、（2）-橘皮素、二氢芹菜素和（2）-杨梅素等为底物，合成了 179.9 mg/L 的柚皮苷、276.6 mg/L 的橙皮苷、249.0 mg/L 的新橙皮苷、30.4 mg/L 的地奥司明和 100.7 mg/L 的新圣草酚。据我们所知，这是首次报道类黄酮-7--二糖的生物合成。
