Tihonov theory and center manifolds for inhibitory mechanisms in enzyme kinetics

In this paper we study the chemical reaction of inhibition, determine the appropriate parameter $epsilon$ for the application of Tihonov's Theorem, compute explicitly the equations of the center manifold of the system and find sufficient conditions to guarantee that in the phase space the curves which relate the behavior of the complexes to the substrates by means of the tQSSA are asymptotically equivalent to the center manifold of the system. Some numerical results are discussed.