Mechanistic Basis of the Michaelis-Menten Equation

6 MECHANISTIC BASIS OF THE MICHAELIS-MENTEN EQUATION Equilibrium Analysis 

To explain their results on the conversion of sucrose to glucose and fructose by the enzyme invertase, Michaelis and Menten proposed in 1913 the following scheme of reactions  

It was assumed that /c i is large, compared with kj, thus, the first part of the reaction could be described by the equilibrium constant for the dissociation of the enzyme-substrate complex Ks = [E][S]/[ES]. The concentrations of S and E at any time are derived from the known initial 

The second step of the reaction is a simple first-order one, and thus  

Hence the overall rate of decline of substrate is described by  

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