Two closed ATP- and ADP-dependent conformations in yeast Hsp90 chaperone detected by Mn(II) EPR spectroscopic techniques

Significance Hsp90 is a homo-dimeric chaperone regulating clients involved in tumorigenesis and signal transduction. Its mechanism of action depends on ATP hydrolysis, which is coupled to a conformational cycle, including “closed” and “open” conformations involving the dimerization of the N-terminal domains, which comprise the ATP binding site. The ATP-bound closed conformation is important for chaperoning activity, while an ADP-bound closed...