Department of Metabolic Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom.
Cold Spring Harb Perspect Biol. 2019 Dec 2;11(12):a034744. doi: 10.1101/cshperspect.a034744.
Glycosylation plays a major role in the structural diversification of plant natural products. It influences the properties of molecules by modifying the reactivity and solubility of the corresponding aglycones, so influencing cellular localization and bioactivity. Glycosylation of plant natural products is usually carried out by uridine diphosphate(UDP)-dependent glycosyltransferases (UGTs) belonging to the carbohydrate-active enzyme glycosyltransferase 1 (GT1) family. These enzymes transfer sugars from UDP-activated sugar moieties to small hydrophobic acceptor molecules. Plant GT1s generally show high specificity for their sugar donors and recognize a single UDP sugar as their substrate. In contrast, they are generally promiscuous with regard to acceptors, making them attractive biotechnological tools for small molecule glycodiversification. Although microbial hosts have traditionally been used for heterologous engineering of plant-derived glycosides, transient plant expression technology offers a potentially disruptive platform for rapid characterization of new plant glycosyltransferases and biosynthesis of complex glycosides.
糖基化在植物天然产物的结构多样化中起着重要作用。它通过修饰相应糖苷配基的反应性和溶解性来影响分子的性质，从而影响细胞定位和生物活性。植物天然产物的糖基化通常由属于碳水化合物活性酶糖苷转移酶 1（GT1）家族的尿苷二磷酸（UDP）依赖性糖基转移酶（UGTs）进行。这些酶将糖从 UDP 激活的糖部分转移到小的疏水性受体分子上。植物 GT1 通常对其糖供体具有高特异性，并将单个 UDP 糖识别为其底物。相比之下，它们通常对受体具有混杂性，这使它们成为小分子糖基化多样化的有吸引力的生物技术工具。尽管微生物宿主传统上被用于植物衍生糖苷的异源工程，但瞬时植物表达技术为快速表征新的植物糖基转移酶和复杂糖苷的生物合成提供了一个潜在的颠覆性平台。
