chaperone Hsp70; DNA biosynthesis; autoregulated heat shock proteins; GO_component: GO:0005737 - cytoplasm; GO_process: GO:0006457 - protein folding; GO_process: GO:0006970 - response to osmotic stress
Function
factor; Chaperones,2.3.4 information transfer; protein related; chaperoning, folding,5.5.1 cell processes; adaptation to stress; osmotic pressure,7.1 location of gene products; cytoplasm
FUNCTION:Participates in initiation and elongation during chromosome replication; it exhibits DNA-dependent ATPase activity and contains distinct active sites for ATP binding, DNA binding, and interaction with dnaC protein, primase, and other prepriming proteins.
SUBUNIT:Homohexamer.
SIMILARITY:Belongs to the helicase family. DnaB subfamily.
Heat shock protein 70, Heat shock 70 kDa protein, HSP70
- Gene name
OrderedLocusNames=b0014, c0019, z0014, ECs0014;
- Comments
FUNCTION:Plays an essential role in the initiation of phage lambda DNA replication, where it acts in an ATP-dependent fashion with the dnaJ protein to release lambda O and P proteins from the preprimosomal complex. DnaK is also involved in chromosomal DNA replication, possibly through an analogous interaction with the dnaA protein. Also participates actively in the response to hyperosmotic shock.
PTM:Autophosphorylated; grpE inhibits the autophosphorylation.
MISCELLANEOUS:The mutants dnaK756(Ts), seg-1 and seg-2 confer temperature sensitivity.
SIMILARITY:Belongs to the heat shock protein 70 family.
FUNCTION:Interacts with dnaK to disassemble a protein complex at the phage lambda origin of replication. Stimulates, jointly with grpE, the ATPase activity of dnaK.
COFACTOR:Binds 2 zinc ions per monomer.
SUBUNIT:Homodimer.
SUBCELLULAR LOCATION:Cytoplasmic.
INDUCTION:By heat shock under the control of the htpR regulatory protein.
Microbiology 1996;142:2595-2602
Defect in export and synthesis of the periplasmic galactose receptor MglB in dnaK mutants of Escherichia coli, and decreased stability of the mglB mRNA.
el Yaagoubi, A., M. Kohiyama, and G. Richarme.
Mol Gen Genet. 1990;223(3):361-8.
Possible involvement of the ugpA gene product in the stable maintenance of mini-F plasmid in Escherichia coli.
Ezaki B, Mori H, Ogura T, Hiraga S.
(
2270076
)
Mol Gen Genet. 1989;218(2):183-9.
Involvement of DnaK protein in mini-F plasmid replication: temperature-sensitive seg mutations are located in the dnaK gene.
Ezaki B, Ogura T, Mori H, Niki H, Hiraga S.
(
2674651
)
J Biol Chem. 1990;265:19244-19248
Aggregated dnaA protein is dissociated and activated for DNA replication by phospholipase or dnaK protein.
Hwang, D. S., E. Crooke, and A. Kornberg.
J Bacteriol. 1994;176:5648-5653
Induction of heat shock proteins by abnormal proteins results from stabilization and not increased synthesis of sigma32 in Escherichia coli.
Kanemori, M., H. Mori, and T. Yura.
Proc Natl Acad Sci U S A. 1984;81:848-852
Major heat shock gene of Drosophila and the Escherichia coli heat-inducible dnaK gene are homologous.
Bardwell, J. C., and E. A. Craig.
J Bacteriol. 1994;176:764-780
DnaK mutants defective in ATPase activity are defective in negative regulation of the heat shock response: expression of mutant DnaK proteins results in filamentation.
McCarty, J. S., and G. C. Walker.
J Bacteriol. 1997;179:445-452
Heat shock regulation of sigma S turnover: a role for DnaK and relationship between stress responses mediated by sigma S and sigma 32 in Escherichia coli.
Muffler, A., M. Barth, C. Marschall, and R. Hengge-Aronis.
Eur J Biochem. 1996;240:78-82
Nucleotide binding to the heat-shock protein DnaK as studied by ESR spectroscopy.
Neuhofen, S., H. Theyssen, J. Reinstein, W. E. Trommer, and P. D. Vogel.
Biochim Biophys Acta. 1989;1009(1):94-8.
A complete deletion mutant of the Escherichia coli dnaKdnaJ operon.
Ohki R, Morita R, Kawamata T, Uchida H, Ohki M.
(
2675977
)
J Bacteriol. 1987;169(1):283-90.
Escherichia coli dnaK null mutants are inviable at high temperature.
Paek KH, Walker GC.
(
3025174
)
J Bacteriol. 1998;180:846-854
Roles of DnaK and RpoS in starvation-induced thermotolerance of Escherichia coli.
Rockabrand, D., K. Livers, T. Austin, R. Kaiser, D. Jensen, R. Burgess, and P. Blum.
J Bacteriol. 1988;170(2):972-9.
The dnaK gene of Escherichia coli functions in initiation of chromosome replication.
Sakakibara Y.
(
2962992
)
Genes Dev. 1990;4:2202-2209
DnaK, DnaJ, and GrpE heat shock proteins negatively regulate heat shock gene expression by controlling the synthesis and stability of sigma 32.
Straus, D., W. Walter, and C. A. Gross.
Proc Natl Acad Sci U S A. 1996;93:10632-10637
Mutations in the C-terminal fragment of DnaK affecting peptide binding.
Burkholder, W. F., X. Zhao, X. Zhu, W. A. Hendrickson, A. Gragerov, and M. E. Gottesman.
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Entry name(Acc.no)
