Figure 1

Hydrophobic interactions stabilize CaM’s EF hand domains. (a) N- and C-terminal domains of Ca²⁺-bound (holo) CaM (PDB 1CLL) with Met residues shown in yellow, Phe residues shown in green and the mutation sites 52 and 125 shown in red. (b) Ca²⁺ binding alters the solvent exposure of CaM’s Met residues (red; PDB 1DMO³⁰ and 1CLL³¹). For simplicity, residue assignment includes initiator Met. The image was generated using PyMOL Molecular Graphics System, Version 1.8³² (https://pymol.org/2/).