Comparison of the calmodulin model with experimental data. Red curve shows the Adair-Klotz equation using the Adair-Klotz constants obtained from the MWC model of calmodulin. Symbols are used to represent data points from various experimental measurements of calmodulin binding to calcium: Circles for Porumb , squares for Crouch and Klee , diamonds for Peersen et al. . The black line represents a fit of all of these data set to the Adair-Klotz equation, which was obtained using the "Non-linear curve-fitting" function in grace http://plasma-gate.weizmann.ac.il/Grace/.