Related Experiment Video
Updated: Jul 10, 2026
07:46
Temperature Response of Soil Organic Matter Decomposition Rates: Construction and Applications of a Temperature Gradient Block
Published on: January 30, 2026
New parameters controlling the effect of temperature on enzyme activity
R M Daniel1, M J Danson, R Eisenthal
1Thermophile Research Unit, School of Science and Engineering, University of Waikato, Hamilton, New Zealand. r.daniel@waikato.ac.nz
Biochemical Society Transactions
|November 23, 2007
Summary
A new Equilibrium Model explains enzyme temperature effects via a reversible active-inactive transition, alongside irreversible denaturation. This model enhances understanding of enzyme thermal behavior and adaptation.
Area of Science:
- Biochemistry
- Enzymology
- Biophysics
Background:
- Enzyme activity is highly sensitive to temperature fluctuations.
- Existing models do not fully capture the reversible mechanisms of enzyme inactivation.
- High temperatures lead to irreversible thermal denaturation, but other reversible processes also affect enzyme function.
Purpose of the Study:
- To introduce a novel Equilibrium Model for enzyme thermal behavior.
- To elucidate the reversible active-inactive transition of enzymes.
- To provide a comprehensive framework for understanding temperature effects on enzyme activity.
Main Methods:
- Development of the Equilibrium Model based on thermal behavior measurements.
- Characterization of the reversible active-inactive transition.
- Determination of new thermal parameters: T(eq) and DeltaH(eq).
- Fitting the model to experimental data.
Main Results:
- The Equilibrium Model accurately describes enzyme activity across temperatures.
- A reversible active-inactive transition is identified as a key mechanism for enzyme activity loss.
- The model incorporates both reversible transitions and irreversible thermal inactivation.
- New parameters T(eq) and DeltaH(eq) quantify the active-inactive transition.
Conclusions:
- The Equilibrium Model offers a more complete explanation of temperature effects on enzymes.
- This model has significant implications for understanding enzyme evolution and environmental adaptation.
- The model provides valuable insights for enzyme engineering in biotechnology.
Related Concept Videos
01:13Introduction to Mechanisms of Enzyme Catalysis
For many years, scientists thought that enzyme-substrate binding took place in a simple "lock-and-key" fashion. This model stated that the enzyme and substrate fit together perfectly in one instantaneous step. However, current research supports a more refined view scientists call induced fit. The induced-fit model expands upon the lock-and-key model by describing a more dynamic interaction between enzyme and substrate. As the enzyme and substrate come together, their interaction causes a mild...
02:28Effect of Temperature Change on Reaction Rate
The Arrhenius equation,
02:55Temperature Dependence on Reaction Rate
The Collision Theory
Atoms, molecules, or ions must collide before they can react with each other. Atoms must be close together to form chemical bonds. This premise is the basis for a theory that explains many observations regarding chemical kinetics, including factors affecting reaction rates.
The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
Atoms, molecules, or ions must collide before they can react with each other. Atoms must be close together to form chemical bonds. This premise is the basis for a theory that explains many observations regarding chemical kinetics, including factors affecting reaction rates.
The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
02:11Effects of Temperature on Free Energy
The spontaneity of a process depends upon the temperature of the system. Phase transitions, for example, will proceed spontaneously in one direction or the other depending upon the temperature of the substance in question. Likewise, some chemical reactions can also exhibit temperature-dependent spontaneities. To illustrate this concept, the equation relating free energy change to the enthalpy and entropy changes for the process is considered:
01:27Factors Influencing Microbial Growth: Temperature
Microorganisms display remarkable adaptations, enabling them to thrive in diverse ecological niches across a wide range of temperatures. Temperature profoundly influences microbial growth by affecting enzymatic activity, membrane fluidity, and other cellular processes.Each microorganism operates within a specific temperature range defined by three cardinal points: minimum, optimum, and maximum. Below the minimum temperature, membranes lose fluidity, halting transport processes. Above the...
02:19Le Chatelier's Principle: Changing Temperature
Consistent with the law of mass action, an equilibrium stressed by a change in concentration will shift to re-establish equilibrium without any change in the value of the equilibrium constant, K. When an equilibrium shifts in response to a temperature change, however, it is re-established with a different relative composition that exhibits a different value for the equilibrium constant.
To understand this phenomenon, consider the elementary reaction:
To understand this phenomenon, consider the elementary reaction: