Tucker G A, Robertson N G, Grierson D
Eur J Biochem. 1981 Mar 16;115(1):87-90. doi: 10.1111/j.1432-1033.1981.tb06201.x.
Polygalacturonase is extractable from ripe tomatoes in two isoenzyme forms, polygalacturonase 1 and 2. These isoenzymes have previously been shown to have substantially different properties although their polypeptides appear similar. Green fruit contain a heat-stable, non-dialysable factor capable of the conversion of polygalacturonase 2 in vitro into another isoenzyme which, on the basis of heat stability, molecular weight and density in caesium chloride, is equivalent to polygalacturonase 1. The amount of this factor extractable from tomato tissue increases during ripening.
多聚半乳糖醛酸酶可以从成熟番茄中以两种同工酶形式提取出来，即多聚半乳糖醛酸酶1和多聚半乳糖醛酸酶2。尽管这两种同工酶的多肽看起来相似，但先前已证明它们具有截然不同的特性。绿色果实含有一种热稳定、不可透析的因子，该因子能够在体外将多聚半乳糖醛酸酶2转化为另一种同工酶，基于热稳定性、分子量和在氯化铯中的密度，这种同工酶等同于多聚半乳糖醛酸酶1。从番茄组织中可提取的这种因子的量在成熟过程中会增加。
