1-O-反式-桂皮酰基-β-D-葡萄吡喃糖是从水果中分离出的一种天然产物。
Strawberry (Fragaria × ananassa) fruit accumulate (hydroxy)cinnamoyl glucose (Glc) esters, which may serve as the biogenetic precursors of diverse secondary metabolites, such as the flavor constituents methyl cinnamate and ethyl cinnamate. Here, we report on the isolation of a cDNA encoding a UDP-Glc:cinnamate glucosyltransferase (Fragaria × ananassa glucosyltransferase 2 [FaGT2]) from ripe strawberry cv Elsanta that catalyzes the formation of 1-O-acyl-Glc esters of cinnamic acid, benzoic acid, and their derivatives in vitro. Quantitative real-time PCR analysis indicated that FaGT2 transcripts accumulate to high levels during strawberry fruit ripening and to lower levels in flowers. The levels in fruits positively correlated with the in planta concentration of cinnamoyl, p-coumaroyl, and caffeoyl Glc. In the leaf, high amounts of Glc esters were detected, but FaGT2 mRNA was not observed. The expression of FaGT2 is negatively regulated by auxin, induced by oxidative stress, and by hydroxycinnamic acids. Although FaGT2 glucosylates a number of aromatic acids in vitro, quantitative analysis in transgenic lines containing an antisense construct of FaGT2 under the control of the constitutive 35S cauliflower mosaic virus promoter demonstrated that the enzyme is only involved in the formation of cinnamoyl Glc and p-coumaroyl Glc during ripening.
草莓(Fragaria × ananassa)果实积累(羟基)肉桂酰葡萄糖(Glc)酯,这些酯可能作为不同次生代谢物的生物合成前体,例如风味成分甲基肉桂酸酯和乙基肉桂酸酯。在这里,我们报道了从成熟草莓cv Elsanta中分离出的编码UDP-Glc:肉桂酸葡萄糖苷转移酶(Fragaria × ananassa葡萄糖苷转移酶2 [FaGT2])的cDNA,该酶在体外催化肉桂酸、苯甲酸及其衍生物的1-O-酰基-Glc酯的形成。定量实时PCR分析表明,FaGT2转录本在草莓果实成熟期间积累到高水平,并在花中降低。果实中的水平与植物体内肉桂酰、对香豆酰和咖啡酰Glc的浓度呈正相关。在叶片中,检测到高量的Glc酯,但未观察到FaGT2 mRNA。FaGT2的表达受生长素的负调控,受氧化应激和羟基肉桂酸的诱导。虽然FaGT2在体外葡萄糖化了许多芳香族酸,但在含有FaGT2反义构建物的转基因线中的定量分析表明,该酶仅参与成熟期间肉桂酰Glc和对香豆酰Glc的形成。