Activation/Inhibition of Cholinesterases by Excess Substrate: Interpretation of the Phenomenological Factor in Steady-State Rate Equation.

Cholinesterases (ChEs) display a non-michaelian behavior with positively charged substrates. In the steady-state rate equation, the b factor describes this behavior: if 1 there is substrate activation, if 1 there is substrate inhibition. The mechanistic significance of the factor was investigated to determine whether this behavior depends on acylation, deacylation or on both steps.