Fig. 4. The interaction of Hsp90α with KU-32, KU-596 and AMP-PNP monitored by methyl-TROSY NMR. (A) Isoleucine residues of Hsp90 that experience changes in chemical shift are mapped (grey spheres) on the structure of dimeric yeast Hsp90 (“closed state”). The assignment of C-Hsp90 fragment is not currently available and the two C-Hsp90 methyl groups that shift are referred as C1 and C2. (B) Selected regions of the 1H–13C HMQC spectrum of Hsp90 in the absence (black) and presence of KU-596 (orange), KU-32 (green) or AMP-PNP (red), showing isoleucine signals that experience changes in chemical shift.
