伴侣分子（GroE）纯化及其催化的重组蛋白质折叠反应

我们自Ｅ．ｃｏｌｉ细胞中纯化出ＧｒｏＥＬ和ＧｒｏＥＳ，对其有活性的分子状态和反应条件进行了探索，结果表明，只有在等摩尔的ＧｒｏＥＬ和ＧｒｏＥＳ以及１ｍｍｏｌ／ＬＡＴＰ和适当浓度的Ｋ＋存在时；才会有较高的催化折叠效率，它可使ｌｍｇ／ｍｌ的ＩＬ－２的正确折叠率由３０％提高到５８％，使ＩＬ－２和ＧＭ－ＣＳＦ的比活性提高１倍以上。它提高重组蛋白质正确拆叠率的关键是可以降低折叠过程中形成聚合体。

GroE Purification and the Refolding of Recombinant Proteins as Facilitated by Chaperones

Found in recent years, chaperones are a new class of proteins which catalyze protein folding reaction in vivo.We purified the GroEL and GroES from E.coli with multicopy plasmid of pGroESL,and studied the active state of the molecule and the optimum reaction condition of GroEL and GroES. Results indicate that good catalyzing efficiency can be achieved only with equal molar of GroEL and GroES, and in the presence of 1mM ATP and suitable concentration of K+. With the action of chaperones, the correct folding ratio of IL-2(at 1mg/ml) increased from 30% to 58%, and the specific activities of IL-2 and GM-OSF were more than doubled. Gel filtration and HPLC result suggests that chaperones can reduce oligomer formation during protein refolding.