Figure 1.

A. Ribbon representation of the crystal structure of TcAChE showing its two subdomains (residues 4–305, purple, and residues 306‐535, red). The entrance to the active‐site gorge, located between the two subdomains, is marked by an arrow. Ser200 and His440, within the catalytic triad, Trp84, in the “anionic” subsite, Tyr121, in the middle of the gorge, and Trp279, in the peripheral anionic site (PAS) at the top of the gorge, are shown as stick models, with carbon atoms colored yellow; B. Close‐up of the active‐site gorge taken from the crystal structure of the galanthamine/TcAChE complex [PDB code 1DX6].29 The protein backbone and the individual residues are colored as in (A). The galanthamine is shown in space‐filling format in green, and above it an ethylene glycol tetramer in magenta.