Kinetic analysis of the opened bicyclic enzyme cascades.

A kinetic analysis of the opened bicyclic enzyme cascade is presented. It includes the time-dependence of the concentrations of the modified and unmodified forms of the interconvertible enzymes, as well as their fractional modifications, from the onset of the reaction to its completion. The transient phase equations obtained allow the definition of new regulatory properties. The expressions corresponding to the concentrations and fractional modification in the steady-state are derived as particular cases of the general transient phase equations. These steady-state expressions agree with those obtained by other authors.