FIGURE 8.

Comparison of smP4-P6 folding thermodynamics and kinetics in Mg²⁺ and Ba²⁺. Folding thermodynamics (A) and kinetics (B) of smP4-P6 as a function of Mg²⁺ (red) and Ba²⁺ (blue). All buffers contained 100 mm Na⁺. Large circles represent the median of all molecules analyzed at the indicated ion concentration, and smaller black circles represent 50 randomly chosen molecules. (See supplemental information for all single molecule data.) Lines in A are empirical Hill fits to the median data points, giving n_Hill = 4.1 for Mg²⁺ and 1.9 for Ba²⁺.