Figure 5.

GdnHCl titrations of mutants and resulting sequential model for HpmA265 unfolding. Titration data and trend lines are presented as in Figure 3 with HpmA265 data provided in black in each panel. The effect of each mutation on HpmA265 are noted by a red arrow for each group of mutations. Cartoon insets show site-specifically mutated residues rendered as spheres and colored by atom type. (A) Constructs targeting the C-terminal subdomain resulting in elimination of the N → I₁ transition (T₁). (B) Constructs targeting the nonpolar subdomain resulting in a shift of the I₁ → I₂ transition (T₂). (C) Representative constructs targeting the polar subdomain resulting in a shift of the I₂ → D transition (T₃). (D) Sequential unfolding model for HpmA265. The subdomain that is unfolded during each transition is named below the arrow.