Figure 3.

Interaction between CaM and peptides derived from CaMBDs of AC1 and AC8. Offline nano-ESI-MS measurements were performed with 10 μM CaM alone (A and B) or in the presence of 10 μM AC1-C1b (C and D), AC8-Nt (E and F), or AC8-C2b (G and H). The measurements were performed with either 200 μM EGTA (A, C, E, and G) or 1 mM Ca²⁺ (B, D, F, and H). Deconvoluted mass spectra are presented. The Ca²⁺-free condition used 200 μM EGTA to mimic the AC assay conditions, which yields negligible concentrations of free Ca²⁺.¹⁹