DnaK as a thermometer: threonine-199 is site of autophosphorylation and is critical for ATPase activity.
- 1 November 1991
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 88 (21) , 9513-9517
- https://doi.org/10.1073/pnas.88.21.9513
Abstract
DnaK, the sole Escherichia coli member of the highly conserved 70-kDa heat shock protein (HSP70) family of proteins, autophosphorylates when incubated with ATP in vitro. We show that threonine-199 is the amino acid that becomes phosphorylated and we demonstrate that threonine-199 is critical for the ATPase activity of DnaK. We also report that both the ATPase and autophosphorylating activities of DnaK increase very strongly over the range of temperatures that is physiologically relevant for E. coli growth. The temperature dependence of either or both of these activities could be of significance with respect to the postulated role of DnaK as a molecular chaperone in helping cells ameliorate the deleterious consequences of elevated temperature. Furthermore, we postulate that DnaK plays a key role in regulation of the heat shock response by serving as a cellular thermometer that directly senses the environmental temperature.Keywords
This publication has 46 references indexed in Scilit:
- DnaK, DnaJ, and GrpE heat shock proteins negatively regulate heat shock gene expression by controlling the synthesis and stability of sigma 32.Genes & Development, 1990
- The E. coli dnaK gene product, the hsp70 homolog, can reactivate heat-inactivated RNA polymerase in an ATP hydrolysis-dependent mannerCell, 1990
- The activity of sigma 32 is reduced under conditions of excess heat shock protein production in Escherichia coli.Genes & Development, 1989
- Phosphorylation of glutaminyl-tRNA synthetase and threonyl-tRNA synthetase by the gene products of dnaK and dnaJ in Escherichia coli K-12 cellsBiochimie, 1989
- Biochemical properties of the Escherichia coli dnaK heat shock protein and its mutant derivativesBiochimie, 1989
- Heat shock protein GroE of Escherichia coli: key protective roles against thermal stress.Genes & Development, 1988
- Effect of bacteriophage M13 infection on phosphorylation of dnaK protein and other Escherichia coli proteinsEuropean Journal of Biochemistry, 1987
- Speculations on the functions of the major heat shock and glucose-regulated proteinsCell, 1986
- Transient rates of synthesis of individual polypeptides in E. coli following temperature shiftsPublished by Elsevier ,1978
- Prediction of protein conformationBiochemistry, 1974