FIGURE 1.

Active site of VX-BChE (A), VR-BChE (B), and CVX-BChE (C) conjugates. Crystals are obtained either by long soaking of BChE crystal in a 1 mm solution of racemic VX (A) or by crystallization of a solution containing 0.1 mm BChE inhibited by 0.4 mm of racemic VR (B) or CVX (C). Key residues are represented by sticks with carbon atoms in blue, oxygen atoms in red, nitrogen atoms in dark blue, and phosphorus atom in orange. Hydrogen bonds are represented by black dashes, and atomic distances are indicated in red (Å). Omit maps are represented in green mesh, contoured at 3.0 σ.