THERMODYNAMIC MECHANISM OF CATALYSIS BY HALOPEROXIDASES

A novel 'thermodynamic' mechanistic rationale of haloperoxidase cataly sis is based on the following two assumptions: (i) the role of enzyme consists only in the rapid equilibration between the halogen-containin g species originating from halide and hydrogen peroxide; (ii) the inte raction between the enzyme and organic substrate is kinetically insign ificant and halogenation occurs as a result of the electrophilic attac k of the active brominating (Br-3(-), Br-2 and HBrO) or chlorinating ( HClO) species at monochlorodimedon indicative of a higher chloride 'sp ecificity' of chloroperoxidase from C. fumago.