In the Michaelis-Menten model, how is the concentration of the enzyme-substrate complex [ES] represented?

In the context of the Michaelis-Menten model of enzyme kinetics, the concentration of the enzyme-substrate complex ([ES]) is derived from the relationships established by the enzyme's total concentration and the concentrations of the free enzyme ([E]) and substrate ([S]).

The Michaelis-Menten equation and model involve several key principles, including the formation and dissociation of the enzyme-substrate complex. The concentration of the enzyme-substrate complex is represented in relation to the total enzyme concentration and the free substrate concentration. Specifically, the equation can be expressed as:

[ [ES] = \frac{([E]_{\text{total}} - [E]) [S]}{K_m + [S]} ]

This implies that the concentration of the substrate, along with the total available enzyme, influences how much of the enzyme is bound to the substrate.

The representation provided in the correct answer indicates that the relationship is built on enzyme and substrate interactions divided by the Michaelis constant ((K_m)), which is critical in understanding the dynamics of how an enzyme interacts with its substrate.

The Michaelis constant ((K_m)) is defined as the substrate concentration at which the reaction velocity is half of the