GROE FACILITATES REFOLDING OF CITRATE SYNTHASE BY SUPPRESSING AGGREGATION
GROE FACILITATES REFOLDING OF CITRATE SYNTHASE BY SUPPRESSING AGGREGATION
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DOI：
10.1021/bi00220a020
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发表时间：
1991-02-12
期刊：
影响因子：
2.9
通讯作者：
KIEFHABER, T
中科院分区：
文献类型：
--
作者：
BUCHNER, J;SCHMIDT, M;KIEFHABER, T
分子伴侣GroE在体内和体外促进正确的蛋白质折叠。以柠檬酸合成酶的复性为模型体系，研究了GOE的作用机制。这种二聚体蛋白质的体外变性几乎是不可逆的，因为重折叠的多肽链迅速聚集，这直接表现为强烈的、浓度依赖的光散射增加。添加GOE和MgATP可显著提高柠檬酸合成酶的活性。GroE抑制了与正确的蛋白质折叠竞争的聚集反应，这一点通过对光散射的特定抑制来表明。GroEL迅速与未折叠或部分折叠的柠檬酸合成酶分子形成复合体。在这个复合体中，复性蛋白受到保护，不会聚集。需要添加GROES和ATP水解来释放与GroEL结合的多肽链，并允许进一步折叠到其最终的活性状态。
The molecular chaperone GroE facilitates correct protein folding in vivo and in vitro. The mode of action of GroE was investigated by using refolding of citrate synthase as a model system. In vitro denaturation of this dimeric protein is almost irreversible, since the refolding polypeptide chains aggregate rapidly, as shown directly by a strong, concentration-dependent increase in light scattering. The yields of reactivated citrate synthase were strongly increased upon addition of GroE and MgATP. GroE inhibits aggregation reactions that compete with correct protein folding, as indicated by specific suppression of light scattering. GroEL rapidly forms a complex with unfolded or partially folded citrate synthase molecules. In this complex the refolding protein is protected from aggregation. Addition of GroES and ATP hydrolysis is required to release the polypeptide chain bound to GroEL and to allow further folding to its final, active state.