Predicted interaction coordinates for S367 and E363 residues. (A) Nonbonded electrostatic plus van der Waals energy computed from 10-ns MD trajectories for the E363 and S367 residues. Maximum interactions with S367 involve residue Q41 and to a lesser extent M36 of CaM, plus residues L345 and N349 on the adjacent KCa3.1 subunit. (B) The strongest interactions with E363 involve residue R352 facing E363 on the adjacent subunit, added to weaker interactions with Q41 of CaM.