Anion activation of dopamine beta-hydroxylase: a kinetic model

1. A theoretical analysis has been made of the mechanism of anion activation of dopamine beta-hydroxylase on the basis of accumulated experimental data. A model is presented that accounts for the numerous different effects of activating anions on the enzyme kinetics. This model has a general validity, since it holds for any of the kinetic mechanisms thus far proposed for dopamine beta-hydroxylase. 2. It has been shown that the results of this analysis have direct implications for the experimental conditions to be used in the study of the dopamine beta-hydroxylase reaction. 3. The present analysis has proved that, under appropriate assumptions, theoretical treatment of nonessential activation, so far limited to the single-substrate case, can be easily extended to steady-state multireactant enzymes.