Figure 4

Surface plasmon resonance. A. SPR sensorgrams (black) of the binding of the MBP peptide (duplicate assays using 2.5, 5, 20, 50, 100, and 200 μM) onto immobilized CaM. Data were fit to the two-state conformational change model, and the resulting fit is shown in red. B. Control experiment for linked reactions (heterogeneity test) by SPR. The sensorgrams have been aligned to the end point of the injection. The injection times are as follows: 1 min (magenta), 3 min (blue), 20 min (green).