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Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions
Published on: April 4, 2014
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Michaelis-Menten kinetics under non-isothermal conditions
Anders Lervik1, Signe Kjelstrup, Hong Qian
1Department of Chemistry, Norwegian University of Science and Technology, Trondheim, Norway. anders.lervik@ntnu.no signe.kjelstrup@ntnu.no.
Physical Chemistry Chemical Physics : PCCP
|November 27, 2014
Summary
This study enhances Michaelis-Menten kinetics by incorporating thermal driving forces, introducing a new term to the enzyme kinetics equation. A derived heat flux equation also reveals heat generation independent of temperature gradients.
Area of Science:
- Biophysics
- Chemical Kinetics
- Non-equilibrium Thermodynamics
Background:
- Michaelis-Menten kinetics is a cornerstone of enzyme reaction description.
- Non-equilibrium thermodynamics predicts coupling between chemical and thermal driving forces.
- Understanding these coupled forces is crucial for advanced biochemical modeling.
Purpose of the Study:
- To extend the Michaelis-Menten kinetics model to include thermal driving forces.
- To derive a new kinetic equation that accounts for the coupling of chemical and thermal energy.
- To develop a companion equation for heat flux in enzymatic reactions.
Main Methods:
- Theoretical extension of the Michaelis-Menten equation.
- Application of non-equilibrium thermodynamics principles.
- Derivation of a heat flux equation for enzymatic systems.
Main Results:
- An additional term was incorporated into the Michaelis-Menten equation, quantifying the coupling effect.
- A novel equation for heat flux was derived, applicable even without a temperature difference.
- The derived thermodynamic relationship is general and mechanism-independent.
Conclusions:
- The extended Michaelis-Menten model provides a more comprehensive description of enzymatic reactions under thermal influence.
- The derived heat flux equation offers new insights into energy dissipation in biochemical processes.
- Experimental verification conditions for the new thermodynamic coupling are outlined.
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