Premium
Detection of a concerted conformational change in the ATPase domain of DnaK triggered by peptide binding
Author(s) -
Slepenkov Sergey V.,
Witt Stephan N.
Publication year - 2003
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(03)00207-2
Subject(s) - peptide , atpase , chemistry , conformational change , chaperone (clinical) , biophysics , cyclic nucleotide binding domain , biochemistry , binding domain , nucleotide , binding site , crystallography , biology , enzyme , medicine , pathology , gene
The molecular chaperone DnaK is composed of two functional domains, the ATPase domain and the substrate‐binding domain. In this report, we show that peptide binding to DnaK can be sensed in real time through a labeled nucleotide bound in the ATPase domain. Specifically, when N 8‐(4‐ N ′‐methylanthraniloylaminobutyl)‐8‐aminoadenosine 5′‐triphosphate (MABA)–ATP·DnaK complexes are rapidly mixed with excess peptide, MABA fluorescence rapidly increases and the rate of increase is proportional to peptide concentration. Analysis of the formation traces yield on and off rate constants that are exactly equal to the rate constants obtained from experiments that directly probe peptide binding to DnaK. These results are the first to show that peptide binding to ATP·DnaK triggers a concerted conformational change in the ATPase domain.