Figure 3:Overlaid double reciprocal plots of initial enzyme velocity at increasing substrate (acetylthiocholine concentrations) in the absence (•) and presence of 51. (A) AChE as enzyme. Km of AChE was 0.15 mM.51 was tested at o (0.3 nM), ▼(1.6 nM) and ∇ (9.5 nM). (B) BChE as enzyme. Km of BChE was 0.54 mM.51 was tested at o (62 nM), ▼(108 nM) and ∇ (153 nM).