Format

Send to

Choose Destination
Protein Sci. 1995 Jun;4(6):1118-23.

Interaction of SecB with intermediates along the folding pathway of maltose-binding protein.

Author information

1
Department of Biochemistry and Biophysics, Washington State University, Pullman 99164-4660, USA.

Abstract

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.

PMID:
7549876
PMCID:
PMC2143153
DOI:
10.1002/pro.5560040610
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center