酿酒葡萄果实中酰基化花色苷生物合成机制的研究

Anthocyanins are important water soluble flavonid pigments in red grapes, which have crucial influence on the color and flavor of their berries. As the last key step in anthocyanin biosynthesis and modification, acylation does not only have great contrubution to the solubility and stablility of anthocyanins, but can also enhance their color representation. Thus, it is important to the organoleptic properties of the red grape berries and their products. However, until now there were no reports about the biosynthesis of acylated anthocyanins in grapes or even other fruits at home and abroad. In this study, by using ‘Cabernet Sauvignon’ and other Vitis vinifera wine grapes as materials, the full length genes of the anthocyanin acyltransferases of BAHD family which are crucial to the biosynthesis of acylated anthocyanins, will be coloned. The basic enzymatic functions and the enzyme kinetics parameters of their recombination proteins will be determined in vitro. The subcellular localizations of the proteins encoded by these genes in plant cells will be identified. And also, the transcriptional expression of these genes in the grape berrys of different varities, regions and vintages during development in our country will be detected and analyzed, as well as the accumulation of their products. The systemic study on the biosynthesis of acylated anthocyanins in wine grapes in this research, will provide essential academic supports for the further investigations of anthocyanin metabolism in wine grapes and other fruits.

花色苷是红葡萄中重要的水溶性类黄酮色素物质，对其果实颜色和风味都有着重要的影响。作为花色苷生物合成与修饰的最后一个关键步骤，酰基化修饰不仅可以提高花色苷的水溶性和稳定性，也可以增进其呈色性，因而对红葡萄果实及其产品的感官品质有着重要的意义。然而截至目前，还未见国内外对葡萄果实乃至其它水果中酰基化花色苷生物合成的相关报道。本研究拟采用‘赤霞珠’等欧亚种酿酒葡萄为试材，对参与酰基化花色苷生物合成的BAHD家族花色苷酰基转移酶的全长基因进行克隆，对其重组蛋白的体外基本酶学功能和酶动力学参数进行测定，对其编码蛋白在植物细胞中的亚细胞定位进行确认，对其在我国不同品种、产区、年份酿酒葡萄果实发育过程中转录表达和产物的积累进行检测和分析。本研究对酿酒葡萄果实酰基化花色苷的生物合成进行系统的研究，将为酿酒葡萄和其它水果花色苷代谢的深入研究提供必要的理论支持。