Model for association of Jdp5 with DnaK-ATP. 1, the p5 moiety of Jdp5 binds to the peptide binding domain of DnaK. Tethering of the Jd is illustrated as multiple DnaK-bound conformations of Jdp5, wherein the p5 moiety is fixed, but the Jd explores alternative orientations. 2, the binding of Jd to the DnaK ATPase domain promotes a conformational change in DnaK that accelerates ATP hydrolysis. The activated DnaK is presumed to be transient, and thus, it is illustrated in brackets. 3, ATP hydrolysis stabilizes the closed conformation of the peptide binding domain. 4, nucleotide exchange reopens the peptide binding domain, permitting the dissociation of the p5 moiety. The association of a DnaJ-client complex with DnaK is predicted to be similar to that of Jdp5, except that non-covalently bound DnaJ can dissociate before nucleotide exchange and opening of the peptide binding domain in DnaK.