Skip to main content
. Author manuscript; available in PMC: 2018 Mar 24.
Published in final edited form as: J Mol Biol. 2016 Dec 21;429(6):858–872. doi: 10.1016/j.jmb.2016.12.014

Fig. 7.

Fig. 7

Working model for the mechanism of action of the DnaK system in collaboration with Hsp90Ec. First, the client protein is bound by DnaK for initial ATP-dependent remodeling, a process that requires DnaJ/CbpA and GrpE (step 1). Next, DnaK, through a direct interaction of the DnaK NBD with the Hsp90Ec middle domain, recruits Hsp90Ec to the client, which further stabilizes the interaction between DnaK and Hsp90Ec (step 2). DnaJ/CbpA may be released at this time. Binding and hydrolysis of ATP by Hsp90Ec triggers conformational changes in the chaperone that lead to client transfer and stabilization of client binding to Hsp90Ec (step 3). DnaK and GrpE may be released at this step. Hsp90Ec promotes further client remodeling and releases the active native client (step 4). Client proteins that do not attain the active conformation may reenter the chaperone cycle.