PMID:9843444

Citation	Pierpaoli, EV, Gisler, SM and Christen, P (1998) Sequence-specific rates of interaction of target peptides with the molecular chaperones DnaK and DnaJ. Biochemistry 37:16741-8
Abstract	The kinetics of complex formation between nine different fluorescence-labeled peptides (7-22 amino acid residues) and DnaK (Hsp70 homologue of Escherichia coli) in the nucleotide-free R state and in the ATP-liganded T state were measured. R-state DnaK (1 microM) formed high-affinity complexes (Kd = 0.06-2 microM) and bound all peptides (22-50 nM) in slow one- or two-step processes with apparent rate constants for the first phase, varying only by a maximum factor of 30 (kobs1 = 0.003-0.084 s-1 at pH 7.0 and 25 degreesC). In contrast, the rates of complex formation between DnaK-ATP and the same peptides (Kd = 2.2-107 microM) have been found previously to vary by 4 orders of magnitude [one- or two-step processes with kobs1 = 0.001-7.9 s-1; Gisler, S. M., Pierpaoli E. V., and Christen, P. (1998) J. Mol. Biol. 279, 833-840]. The slow and relatively uniform rates of peptide binding to the R state might be determined by the fraction of time during which the alpha-helical lid above the peptide-binding site is open. The faster and widely divergent rates of binding to the open T state might reflect sequence-specific conformational rearrangements in the peptide-binding site and perhaps of the peptide itself. The different rates of association with DnaK-ATP suggest a kinetic partitioning of target sequences in which only slowly interacting segments of polypeptides are channeled into the chaperone cycle.
Links	PubMed Online version:10.1021/bi981762y
Keywords	2-Naphthylamine/analogs & derivatives; 2-Naphthylamine/metabolism; Adenosine Triphosphate/deficiency; Adenosine Triphosphate/metabolism; Amino Acid Sequence; Bacterial Proteins/chemistry; Bacterial Proteins/metabolism; Escherichia coli; Escherichia coli Proteins; Fluorescent Dyes/metabolism; HSP40 Heat-Shock Proteins; HSP70 Heat-Shock Proteins/chemistry; HSP70 Heat-Shock Proteins/metabolism; Heat-Shock Proteins/chemistry; Heat-Shock Proteins/metabolism; Ligands; Macromolecular Substances; Molecular Sequence Data; Peptides/chemistry; Peptides/metabolism; Protein Binding; Spectrometry, Fluorescence
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.