Flexibility of active-site gorge aromatic residues and non-gorge aromatic residues in acetylcholinesterase

Abstract

The presence of an unusually large number of aromatic residues in the active–site gorge of acetylcholinesterase has been a topic of great interest. Flexibility of these residues has been suspected to be a key player in controlling ligand traversal in the gorge. This raises the question of whether the over–representation of aromatic residues in the gorge implies higher–than–normal flexibility of those residues. The current study suggests that it does not. Large changes in the hydrophobic cross–sectional area due to dihedral oscillations are probably the reason behind their presence in the gorge.