INTERACTION OF SECB WITH INTERMEDIATES ALONG THE FOLDING PATHWAY OF MALTOSE-BINDING PROTEIN

被引:20
作者
DIAMOND, DL [1 ]
STROBEL, S [1 ]
CHUN, SY [1 ]
RANDALL, LL [1 ]
机构
[1] WASHINGTON STATE UNIV, DEPT BIOCHEM & BIOPHYS, PULLMAN, WA 99164 USA
关键词
CHAPERONES; FOLDING INTERMEDIATES; SECB;
D O I
10.1002/pro.5560040610
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
SecB, a molecular chaperone involved in protein export in Escherichia coli, displays the remarkable ability to selectively bind many different polypeptide ligands whose only common feature is that of being nonnative. The selectivity is explained in part by a kinetic partitioning between the folding of a polypeptide and its association with SecB. SecB has no affinity for native, stably folded polypeptides but interacts tightly with polypeptides that are nonnative. In order to better understand the nature of the binding, we have examined the interaction of SecB with intermediates along the folding pathway of maltose-binding protein. Taking advantage of forms of maltose-binding protein that are altered in their folding properties, we show that the first intermediate in folding, represented by the collapsed state, binds to SecB, and that the polypeptide remains active as a ligand until it crosses the final energy barrier to attain the native state.
引用
收藏
页码:1118 / 1123
页数:6
相关论文
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