Figure 7
The closed state of Ca2+-bound calmodulin [PDB:2BBM] is obtained by another conformational change when a peptide is bound to the open state ([PDB:1CLL], shown faded), causing the two globular domains to "wrap" around the peptide (not shown). The axis of motion (blue) of the moving cluster (green) relative to the pinned cluster (red) is computed on the closed state and is consistent with the motion.