[A model of enzymatic kinetics].

In this Note, we study a system of differential equations representing the kinetics of an enzymatic reaction. For a closed system, and in the domain where it has a biological significance, it is shown that: (i) there exists a unique equilibrium point, which is an asymptotically stable point; (ii) if several enzymes act on the same substrates, the equilibrium values of the substrates concentrations take their values within the range of the equilibrium values achieved with each of these enzymes, (iii) the kinetics of the reaction can be approached by a single first-order differential equation, which may be seen as a generalization of the Michaelis equation.