Figure 3: Ap5a-bound Y171W simultaneously populates both open and closed conformations.
From: Structural basis for catalytically restrictive dynamics of a high-energy enzyme state
(a) The diffusion coefficients of the wild type, P177A and Y171W AdK variants show that Ap5a-bound Y171W populates both open and closed structures. The bound open conformation corresponds to the high-energy state shown in red in Fig. 1c. (b) The relative change in diffusion coefficient between the apo- and Ap5a-bound states correlates with the difference in unfolding enthalpy between these states (wild type in red, P177A in blue and Y171W in cyan). (c) Build-up curves for residue-specific proton exchange on the millisecond timescale. Solid and dotted lines correspond to the two exchanging peaks observed for Ap5a-bound Y171W. Residue Ile179 (labelling on right y axis) is the only residue shown on the graph whose solvent exchange rate differs significantly between the two states.
