Structural identifiability analysis of parameters for two-site, three-conformation binding model ( Fig. 7 C , left). (A) Matrix representation of system of equations obtained by evaluating linearized binding relation at 11 ligand concentrations x0 through x10. Dashed black, red, and blue boxes indicate identical columns in design matrix and corresponding parameters in parameter vector derived from states with zero, one, and two bound ligands, respectively. (B) Reduced matrix equation obtained by summing parameters in dashed boxes in A. This operation causes the identical black, red, and blue columns to collapse into a single black, single red, and single blue column in the reduced design matrix. (C) General form of reduced matrix equation in B, in which model-specific parameters are replaced by model-independent fit parameters {p0, p1, p2}.
