Dnaj
Mostrando 13-24 de 183 artigos, teses e dissertações.
-
13. Mutations in the DnaK chaperone affecting interaction with the DnaJ cochaperone
Hsp70 chaperones assist protein folding by ATP-controlled cycles of substrate binding and release. ATP hydrolysis is the rate-limiting step of the ATPase cycle that causes locking in of substrates into the substrate-binding cavity of Hsp70. This key step is strongly stimulated by DnaJ cochaperones. We show for the Escherichia coli Hsp70 homolog, DnaK, that s
The National Academy of Sciences.
-
14. A zinc finger-like domain of the molecular chaperone DnaJ is involved in binding to denatured protein substrates.
The Escherichia coli heat-shock protein DnaJ cooperates with the Hsp70 homolog DnaK in protein folding in vitro and in vivo. Little is known about the structural features of DnaJ that mediate its interaction with DnaK and unfolded polypeptide. DnaJ contains at least four blocks of sequence representing potential functional domains which have been conserved t
-
15. Cloning, nucleotide sequence, and regulatory analysis of the Lactococcus lactis dnaJ gene.
The dnaJ gene of Lactococcus lactis was isolated from a genomic library of L. lactis NIZO R5 and cloned into pUC19. Nucleotide sequencing revealed an open reading frame of 1,137 bp in length, encoding a protein of 379 amino acids. The deduced amino acid sequence showed homology to the DnaJ proteins of Escherichia coli, Mycobacterium tuberculosis, Bacillus su
-
16. Physiological consequences of DnaK and DnaJ overproduction in Escherichia coli.
The physiological consequences of molecular chaperone overproduction in Escherichia coli are presented. Constitutive overproduction of DnaK from a multicopy plasmid containing large chromosomal fragments spanning the dnaK region resulted in plasmid instability. Co-overproduction of DnaJ with DnaK stabilized plasmid levels. To examine the effects of altered l
-
17. Control of folding and membrane translocation by binding of the chaperone DnaJ to nascent polypeptides.
Recent evidence supports the view that cellular protein folding may be mediated by molecular chaperones. A fundamental question concerns the stage in its biogenesis at which the folding protein makes first contact with these components. We show here by crosslinking that the chaperone DnaJ binds nascent ribosome-bound polypeptide chains as short as 55 residue
-
18. An analogue of the DnaJ molecular chaperone in Escherichia coli.
Escherichia coli DnaJ functions as a typical molecular chaperone in coordination with other heat shock proteins such as DnaK and GrpE in a variety of cellular processes. In this study, it was found that E. coli possesses an analogue of DnaJ, as judged from not only its primary structure but also its possible function. This protein, named CbpA (for curved DNA
-
19. Genus-specific polymerase chain reaction for the mycobacterial dnaJ gene and species-specific oligonucleotide probes.
Identification of tuberculous and nontuberculous mycobacteria by biochemical methods is a long-term process that takes up to 8 weeks for completion and requires expertise to interpret the results. In order to detect and differentiate the major pathogenic mycobacterial species, we developed genus-specific primers that amplify the dnaJ gene from the broad spec
-
20. The Escherichia coli DjlA and CbpA Proteins Can Substitute for DnaJ in DnaK-Mediated Protein Disaggregation
The DnaJ (Hsp40) protein of Escherichia coli serves as a cochaperone of DnaK (Hsp70), whose activity is involved in protein folding, protein targeting for degradation, and rescue of proteins from aggregates. Two other E. coli proteins, CbpA and DjlA, which exhibit homology with DnaJ, are known to interact with DnaK and to stimulate its chaperone activity. Al
American Society for Microbiology.
-
21. The DnaJ chaperone catalytically activates the DnaK chaperone to preferentially bind the sigma 32 heat shock transcriptional regulator.
In Escherichia coli the heat shock response is under the positive control of the sigma 32 transcription factor. Three of the heat shock proteins, DnaK, DnaI, and GrpE, play a central role in the negative autoregulation of this response at the transcriptional level. Recently, we have shown that the DnaK and DnaJ proteins can compete with RNA polymerase for bi
-
22. Escherichia coli DnaJ and GrpE heat shock proteins jointly stimulate ATPase activity of DnaK.
The products of the Escherichia coli dnaK, dnaJ, and grpE heat shock genes have been previously shown to be essential for bacteriophage lambda DNA replication at all temperatures and for bacterial survival under certain conditions. DnaK, the bacterial heat shock protein hsp70 analogue and putative chaperonin, possesses a weak ATPase activity. Previous work h
-
23. DnaK, DnaJ and GrpE form a cellular chaperone machinery capable of repairing heat-induced protein damage.
Members of the conserved Hsp70 chaperone family are assumed to constitute a main cellular system for the prevention and the amelioration of stress-induced protein damage, though little direct evidence exists for this function. We investigated the roles of the DnaK (Hsp70), DnaJ and GrpE chaperones of Escherichia coli in prevention and repair of thermally ind
-
24. Interaction of the Hsp70 molecular chaperone, DnaK, with its cochaperone DnaJ
Chaperones of the Hsp70 family bind to unfolded or partially folded polypeptides to facilitate many cellular processes. ATP hydrolysis and substrate binding, the two key molecular activities of this chaperone, are modulated by the cochaperone DnaJ. By using both genetic and biochemical approaches, we provide evidence that DnaJ binds to at least two sites on
The National Academy of Sciences.