A note on the reverse Michaelis–Menten kinetics

We theoretically derived a general equation describing the enzyme kinetics that could be further simplified to the typical Michaelis–Menten (M–M) kinetics or the reverse M–M equation (RM–M) under the condition of S ≈ S1 >> E0 or S1 E0. Both the M–M and the RM-M-SW are appropriate to field soil conditions with S >> E0 given different values of specific reaction rate (k3) and half-saturation constant (Ks). In contrast to M–M and RM–M–SW models, the RM–M model is not applicable to field conditions because of its limited application to one substrate with a simple enzyme system. However, we demonstrate that the best formulation for the process of enzyme-mediated decomposition may vary depending on whether the process is limited by substrate or enzyme availability. ► We theoretically derive a general equation describing the enzyme kinetics. ► This equation can be simplified to the Michaelis–Menten (M–M) or reverse M–M (RM–M). ► Schimel and Weintraub RM–M (RM–M–SW) is derived from the Langmuir equation. ► We compare the three models by their assumptions, sensitivities and applications.