PMID:9405415
| Citation |
Aoki, K, Taguchi, H, Shindo, Y, Yoshida, M, Ogasahara, K, Yutani, K and Tanaka, N (1997) Calorimetric observation of a GroEL-protein binding reaction with little contribution of hydrophobic interaction. J. Biol. Chem. 272:32158-62 |
|---|---|
| Abstract |
Binding of Escherichia coli chaperonin, GroEL, to substrate proteins with non-native structure, reduced alpha-lactalbumin (rLA) and denatured pepsin, were analyzed by isothermal titration calorimetry at various temperatures in the presence of salt (0.2 M KCl). Both proteins bound to GroEL with 1:1 stoichiometry and micromolar affinity at all temperatures tested. However, thermodynamic properties of their binding to GroEL are remarkably different from each other. While heat capacity changes (DeltaCp) of rLA-GroEL binding showed large negative values, -4.19 kJ mol-1 K-1, that of denatured pepsin-GroEL binding was only -0.2 kJ mol-1 K-1. These values strongly indicate that the hydrophobic interaction is a major force of rLA-GroEL binding but not so for denatured pepsin-GroEL binding. When salt was omitted from the solution, the affinity and DeltaCp of the rLA-GroEL binding reaction were not significantly changed whereas denatured pepsin lost affinity to GroEL. Thus, in the non-native protein-GroEL binding reaction, thermodynamic properties, as well as the effect of salt, differ from protein to protein and hydrophobic interaction may not always be a major driving force. |
| Links | |
| Keywords |
Calorimetry/methods; Chaperonin 60/chemistry; Chaperonin 60/metabolism; Chromatography, High Pressure Liquid; Circular Dichroism; Escherichia coli/metabolism; Hydrogen-Ion Concentration; Protein Binding; Thermodynamics |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.