Temperature-controlled activity of DnaK-DnaJ-GrpE chaperones: protein-folding arrest and recovery during and after heat shock depends on the substrate protein and the GrpE concentration.
Details
Serval ID
serval:BIB_1BFA45DEA931
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Temperature-controlled activity of DnaK-DnaJ-GrpE chaperones: protein-folding arrest and recovery during and after heat shock depends on the substrate protein and the GrpE concentration.
Journal
Biochemistry
ISSN
0006-2960 (Print)
ISSN-L
0006-2960
Publication state
Published
Issued date
1998
Volume
37
Number
27
Pages
9688-9694
Language
english
Abstract
Heat-shock proteins DnaK, DnaJ, and GrpE (KJE) from Escherichia coli constitute a three-component chaperone system that prevents aggregation of denatured proteins and assists the refolding of proteins in an ATP-dependent manner. We found that the rate of KJE-mediated refolding of heat- and chemically denatured proteins is decreased at high temperatures. The efficiency and reversibility of protein-folding arrest during and after heat shock depended on the stability of the complex between KJE and the denatured proteins. Whereas a thermostable protein was released and partially refolded during heat shock, a thermolabile protein remained bound to the chaperone. The apparent affinity of GrpE and DnaJ for DnaK was decreased at high temperatures, thereby decreasing futile consumption of ATP during folding arrest. The coupling of ATP hydrolysis and protein folding was restored after the stress. This strongly indicates that KJE chaperones are heat-regulated heat-shock proteins which can specifically arrest the folding of aggregation-prone proteins during stress and preferentially resume refolding under conditions that allow individual proteins to reach and maintain a stable native conformation.
Keywords
Bacterial Proteins/chemistry, Bacterial Proteins/metabolism, Escherichia coli/metabolism, Escherichia coli Proteins, HSP40 Heat-Shock Proteins, HSP70 Heat-Shock Proteins/chemistry, HSP70 Heat-Shock Proteins/metabolism, Heat-Shock Proteins/chemistry, Heat-Shock Proteins/metabolism, Hot Temperature, Molecular Chaperones/chemistry, Molecular Chaperones/metabolism, Protein Folding, Substrate Specificity
Pubmed
Web of science
Create date
24/01/2008 20:02
Last modification date
20/08/2019 12:52