果胶降解相关酶与果实成熟软化

Advances in research on the relationship between pectolytic enzymes and fruit softening

果胶降解相关酶广泛存在于植物体的各个部分,目前在果实组织中已发现多种,主要包括内切多聚半乳糖醛酸酶、外切多聚半乳糖醛酸酶、果胶甲酯酶、果胶裂解酶、β-半乳糖苷酶、α-L-阿拉伯呋喃糖苷酶和鼠李糖半乳糖醛酸酶,此类酶能使果胶多糖发生降解,进而使细胞间失去黏结作用,胞壁结构瓦解,从而导致果实组织松弛,质地下降。综述了果胶降解相关酶及其相应基因对果实成熟软化作用的研究进展,同时对果实成熟软化研究中存在的问题和将来的研究方向进行了探讨。

Pectolytic enzymes are widespread in plants and mainly include pectinmethylesterase（PME）,pectate lyase（PEL）,endo-polygalacturonase（endo-PG）,exo-polygalacturonase（exo-PG）,β-galactosidase,α-L-arabinofuranosidase and rhamnogalacturonase in fruit tissues.They constitute a unique group of enzymes that are responsible for the degradation of pectin and pectic substances in fruit cell walls,and make cell-to-cell separation and disassembly of the cell wall structure and lead to fruit-tissue softening.This review summarizes our current knowledge about pectolytic enzymes and their corresponding genes that participate in the degradation of pectin polysaccharides in fruit plants.In addition,the existing problems and direction of fruit softening study in near future are put forward.