Figure 5.

Nonlinear curve fitting of real-time NMR data. (a) Fraction of CA2 bound to AAZ (left) and MZA (center), and disulfide-oxidized SOD1 (right) fitted with single exponential build-up curves. (b) Fraction of CA2 bound to AAZ (left) and MZA (right) fitted with a membrane diffusion-limited model.¹⁶ (c) Fraction of disulfide-oxidized SOD1 fitted with a biexponential build-up curve. The exponential time constants (t₁, t₂), the permeability coefficients × membrane area (K_pA) and the apparent dissociation constants (K_d^APP) are reported in each panel. Raw data and residuals are shown as gray and red dots, respectively. Best-fit curves are shown as continuous red lines. In (b), diffusion-limited binding curves with values of K_d^APP fixed to the K_I determined in vitro (K_I^AAZ = 12 × 10^–9 M; K_I^MZA = 14 × 10^–9 M) are shown as dashed red lines.