Solution conformation of wild-type E. coli Hsp70 (DnaK) chaperone complexed with ADP and substrate
Solution conformation of wild-type E. coli Hsp70 (DnaK) chaperone complexed with ADP and substrate
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DOI：
10.1073/pnas.0903503106
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发表时间：
2009-05-26
影响因子：
11.1
通讯作者：
Zuiderweg, Erik R. P.
中科院分区：
文献类型：
--
作者：
Bertelsen, Eric B.;Chang, Lyra;Zuiderweg, Erik R. P.
DnaK是来自大肠杆菌的典型Hsp 70分子伴侣蛋白。与其他热休克蛋白70一样，DnaK包含两个主要结构域：一个44 kDa的N-末端核苷酸结合结构域（NBD），含有ATP酶活性;一个25 kDa的底物结合结构域（SBD），含有底物结合位点。在这里，我们报告了野生型，全长DnaK，复合肽NRLLLTG和ADP的实验结构。它是通过使用NMR残余偶极耦合和自旋标记方法在水溶液中获得的，并且是基于分离的NBD和SBD的可用晶体结构。通过使用动力学方法，我们确定NBD和SBD是松散连接的，并且可以相对于彼此在+/- 35度的圆锥中移动。结构域之间的接头区域是动态无规卷曲。然而，可以定义一个平均结构。这种结构将SBD置于NBD的亚结构域IA的附近，并表明SBD在该区域与NBD碰撞以建立变构通讯。
DnaK is the canonical Hsp70 molecular chaperone protein from Escherichia coli. Like other Hsp70s, DnaK comprises two main domains: a 44-kDa N-terminal nucleotide-binding domain (NBD) that contains ATPase activity, and a 25-kDa substrate-binding domain (SBD) that harbors the substrate-binding site. Here, we report an experimental structure for wild-type, full-length DnaK, complexed with the peptide NRLLLTG and with ADP. It was obtained in aqueous solution by using NMR residual dipolar coupling and spin labeling methods and is based on available crystal structures for the isolated NBD and SBD. By using dynamics methods, we determine that the NBD and SBD are loosely linked and can move in cones of +/- 35 degrees with respect to each other. The linker region between the domains is a dynamic random coil. Nevertheless, an average structure can be defined. This structure places the SBD in close proximity of subdomain IA of the NBD and suggests that the SBD collides with the NBD at this area to establish allosteric communication.