  Based on our experience in kinetic modeling of coupled multiple metabolic
pathways we propose a generic rate equation for the dynamical modeling of
metabolic kinetics. Its symmetric form makes the kinetic parameters (or
functions) easy to relate to values in database and to use in computation. In
addition, such form is workable to arbitrary number of substrates and products
with different stoichiometry. We explicitly show how to obtain such rate
equation exactly for various binding mechanisms. Hence the proposed rate
equation is formally rigorous. Various features of such a generic rate equation
are discussed. For irreversible reactions, the product inhibition which
directly arise from enzymatic reaction is eliminated in a natural way. We also
discuss how to include the effects of modifiers and cooperativity.
