Celebrating the 100 years of Michaelis-Menten kinetics

A Special Issue of FEBS Letters is celebrating “A century of Michaelis-Menten kinetics”. We contributed to this issue with a paper titled “The average enzyme principle”. Remember the term for the enzyme concentration, E, in the Michaelis-Menten equation? What if that term becomes E(t), i.e. it depends explicitly on time, for example due to regulation? We show that, over a given time interval, the net metabolite changes depend only on the time average of E(t). The theorem can be generalized to a network of synchronously regulated reactions.