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PubMed · 9108300

Ligands regulate GroEL thermostability.

A K Surin·N V Kotova·I A Kashparov·V V Marchenkov·Marchenkova SYu·G V Semisotnov
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Abstract

Escherichia coli heat-shock proteins GroEL and GroES stimulate (in an ATP-dependent manner) the folding of various proteins. In this study scanning microcalorimetry was applied to investigate GroEL thermostability in the presence of its ligands. Mg2+ and K+ ions stabilize while ADP destabilizes the GroEL molecule against the action of temperature. Furthermore, ADP essentially increases the number of binding sites for the hydrophobic probe (ANS) and the number of GroEL SH-groups accessible to Ellman's reagent as well as the accessibility of the protein to the action of trypsin. The interaction of GroEL with GroES in the presence of Mg2+-ADP eliminates the destabilizing effect of ADP on the GroEL molecule against the action of temperature and Ellman's reagent but does not change its hydrophobicity and accessibility to trypsin.

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Adenosine DiphosphateCalorimetry, Differential ScanningChaperonin 10Chaperonin 60Escherichia coliHot TemperatureLigandsProtein ConformationProtein DenaturationSolutionsThermodynamicsTrypsinJournal ArticleResearch Support, Non-U.S. Gov't

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A K Surin, N V Kotova, I A Kashparov, V V Marchenkov, Marchenkova SYu, G V Semisotnov. 1997-04-01. Ligands regulate GroEL thermostability.. https://doi.org/10.1016/s0014-5793(97)00199-3

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