Fig. 4.

Comparison of denaturant-independent exchange events in I53A and wt*. (a) "Local fluctuations" mapped onto the crystal structure of I53A. Dark balls are amide protons that exchange by denaturant-independent events in both I53A and wt*; light balls represent new events in I53A (i.e., not seen in wt*). (b) Free energies of local fluctuations in wt* and I53A are compared. Only residues that exchange through a local fluctuation in both proteins are shown. A line with a slope of 1 is included to simulate the case where I53A ΔG_FL = wt* ΔG_FL. (c) Free energy of all local fluctuations in I53A (black bars) and wt* (gray bars).