Llorca O, Marco S, Carrascosa J L, Valpuesta J M
Centro Nacional de Biotecnología, CSIC, universidad Autónoma de Madrid, Spain.
FEBS Lett. 1994 May 30;345(2-3):181-6. doi: 10.1016/0014-5793(94)00432-3.
The incubation of chaperonins cpn60 (GroEL) and cpn10 (GroES) from E. coli in the presence of Mg-ATP and KCl generates the formation, as revealed by electron microscopy, of GroEL-GroES complexes with a symmetrical shape in which one toroidal GroES oligomer is bound to each end of the tetradecameric GroEL aggregate (1:2 GroEL:GroES oligomer molar ratio). The symmetrical complexes are not observed in the presence of ADP or the non-hydrolyzable ATP analog, ATP gamma S, where only asymmetrical complexes (1:1 GroEL:GroES oligomer molar ratio) are formed. These results suggest that ATP hydrolysis is required for the formation of symmetrical complexes.
在Mg-ATP和KCl存在的情况下，对来自大肠杆菌的伴侣蛋白cpn60（GroEL）和cpn10（GroES）进行孵育，通过电子显微镜观察发现，会形成具有对称形状的GroEL-GroES复合物，其中一个环形GroES寡聚体与十四聚体GroEL聚集体的每一端结合（GroEL:GroES寡聚体摩尔比为1:2）。在存在ADP或不可水解的ATP类似物ATPγS的情况下未观察到对称复合物，此时仅形成不对称复合物（GroEL:GroES寡聚体摩尔比为1:1）。这些结果表明，ATP水解是形成对称复合物所必需的。
