Effect of reversible AChE inhibitors on the binding of MB to TcAChE as monitored by absorption spectroscopy. (A) Displacement of MB by EDR. Concentrations were TcAChE, 12 μM; MB, 5 μM; EDR, 60 μM. •, MB; ▪, MB + TcAChE; ▴, MB + TcAChE + EDR. (B) Displacement of MB by PROP. Concentrations were TcAChE, 12 μM; MB, 5 μM; PROP, 60 μM. •, MB; ▪, MB + TcAChE; ▴, MB + TcAChE + PROP. (C) Displacement of MB by EDR+PROP or by BW. Concentrations were TcAChE, 5.2 μM; MB, 2.5 μM; EDR, 60 μM; PROP, 60 μM; BW, 40 μM. •, MB; ▪, MB + TcAChE; ▴, MB + TcAChE + EDR + PROP; ○, MB + TcAChE + BW.