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研究分子伴侣对解决蛋白质折叠的理论问题及基因工程包涵体的实际问题是很有用的。本文讨论的是Ｅ．ｃｏｌｉ的分子伴侣－属于ｈｓｐ６０家族的ＧｒｏＥＬ蛋白及其辅助蛋白ＧｒｏＥＳ。重组质粒ｐＧｒｏＥＳＬ含有大肠杆菌的ｇｒｏＥＬ和ｇｒｏＥＳ基因。利用这个表达载体，经摇瓶发酵，ＩＰＴＧ诱导表达大量的ＧｒｏＥＬ和ＧｒｏＥＳ蛋白。破菌后，上清经ＤＥ５２—ｃｅｌｕｌｏｓｅ柱层析，硫酸铵分级沉淀，ＳｅｐｈａｃｒｙｌＳ－２００和ＤＥＡＥ－Ｓｅｐｈａｒｏｓｅ柱层析，得到纯度分别为８５％和８０％的ＧｒｏＥＬ和ＧｒｏＥＳ蛋白。ＳＤＳ－ＰＡＧＥ结果显示ＧｒｏＥＬ和ＧＳ蛋白亚基的分子量与理论值相符，同时还定到了ＧｒｏＥＬ蛋白的ＡＴＰ水解酶活力。这种纯化方法操作简单，重复性好，并且可同时得到ＧｒｏＥＬ和ＧｒｏＥＳ蛋白。这两种蛋白可进一步用于体外变性蛋白重折叠的研究
It is useful to study molecular chaperones to solve the theoretical problems of protein folding and the practical problems of genetic engineering inclusion bodies. This article discusses the E. coli chaperone - belongs to the hsp60 family of GroEL protein and its accessory protein GroES. The recombinant plasmid pGroESL contains the groEL and groES genes of E. coli. Using this expression vector, IPTG induced the expression of a large number of GroEL and GroES proteins by shake flask fermentation. After the bacteria were broken, the supernatant was subjected to DE52-celulose column chromatography, ammonium sulfate fractionation, Sephacryl S-200 and DEAE-Sepharose column chromatography to obtain GroEL and GroES proteins with the purity of 85% and 80% respectively. The results of SDS-PAGE showed that the molecular weights of GroEL and GS subunits were in agreement with the theoretical value, and the ATPase activity of GroEL protein was also determined. This purification method is simple and reproducible, and provides both GroEL and GroES proteins. Both of these proteins can be further used to study the refolding of denatured proteins in vitro