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bioRxiv · 10.1101/2023.09.28.559798

The unreasonable effectiveness of the total quasi-steady state approximation, and its limitations

Eilertsen, J.·Schnell, S.·Walcher, S.
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Abstract

In this note, we discuss the range of parameters for which the total quasi-steady-state approximation of the Michaelis-Menten reaction mechanism holds validity. We challenge the prevalent notion that total quasi-steady-state approximation is "roughly valid" across all parameters, showing that its validity cannot be assumed, even roughly, across the entire parameter space -- when the initial substrate concentration is high. On the positive side, we show that the linearized one-dimensional equation for total substrate is a valid approximation when the initial reduced substrate concentration s0/KM is small. Moreover, we obtain a precise picture of the long-term time course of both substrate and complex.

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Eilertsen, J., Schnell, S., Walcher, S.. 2023-09-29. The unreasonable effectiveness of the total quasi-steady state approximation, and its limitations. https://doi.org/10.1101/2023.09.28.559798

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