Intermediate time scale in the first product formation time distribution of Michaelis-Menten kinetics with inhibitors

Arthur M S Carvalho1, Gerson C Duarte-Filho1, Fernando A N Santos2

  • 1Universidade Federal de Sergipe, Departamento de Física, 49107-230 São Cristóvão, Sergipe, Brazil.

Physical Review. E
|April 18, 2026
PubMed

Insights

This study introduces a stochastic analysis of Michaelis-Menten kinetics with inhibitors, revealing complex behaviors like inhibitor-activator duality and a new timescale in enzymatic reactions.

Area of Science:

  • Biochemistry
  • Chemical Kinetics
  • Theoretical Chemistry

Background:

  • Michaelis-Menten kinetics is fundamental to enzyme kinetics and metabolic processes.
  • Understanding enzymatic reactions with inhibitory mechanisms is crucial for biological systems.

Purpose of the Study:

  • To perform a stochastic analysis of Michaelis-Menten kinetics incorporating inhibitory mechanisms.
  • To explore the application of Fock space formalism to inhibited enzymatic reactions.
  • To characterize reaction dynamics and product formation times under inhibition.

Main Methods:

  • Stochastic analysis of Michaelis-Menten kinetics.
  • Application of Fock space formalism to reformulate the master equation.
  • Examination of reversible inhibitions and inhibitor-activator duality.
  • Calculation of the first product formation time distribution.

Main Results:

  • Identified stiffness behavior in all examined inhibition scenarios.
  • Demonstrated the capture of inhibitor-activator duality in partial inhibition.
  • Observed an emergent intermediate timescale in product formation time distribution.
  • Showcased the utility of Fock space formalism for low-copy-number reactions.

Conclusions:

  • The Fock space formalism provides a powerful framework for analyzing inhibited enzymatic reactions.
  • Inhibitory mechanisms introduce complex dynamics, including dual roles for inhibitors and novel timescales.
  • The study offers new perspectives on the behavior of biochemical reactions under inhibition.

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