INACTIVATION OF CRYSTALLINE TRYPSIN
1Laboratories of The Rockefeller Institute for Medical Research, Princeton, N. J.
The Journal of General Physiology
|October 30, 2009
Summary
Trypsin inactivation can be reversible or irreversible, depending on pH and temperature. Reversible denaturation occurs at alkaline pH, while irreversible denaturation and hydrolysis happen at extreme pH values or high temperatures.
Area of Science:
- Biochemistry
- Enzymology
Background:
- Trypsin is a key digestive enzyme crucial for protein hydrolysis.
- Understanding trypsin stability is vital for its applications in research and industry.
- Enzyme inactivation mechanisms are complex and influenced by environmental factors like pH and temperature.
Purpose of the Study:
- To investigate the inactivation rates of crystalline trypsin solutions.
- To characterize the nature of products formed during trypsin inactivation.
- To determine the influence of pH and temperature on trypsin stability and activity.
Main Methods:
- Studied inactivation of crystalline trypsin solutions at various pH levels and temperatures below 37°C.
- Analyzed reversible and irreversible denaturation processes.
- Monitored formation of reaction products and changes in enzyme activity.
Main Results:
- Trypsin inactivation can be reversible (denatured protein equilibrium) or irreversible (product formation).
- Reversible inactivation increases with pH (8.0-12.0) and temperature, shifting equilibrium towards denaturation.
- Irreversible inactivation occurs at extreme pH (<2.0 and >13.0) and high temperatures, involving denaturation and hydrolysis, with specific reaction kinetics (mono- and bimolecular) observed across different pH ranges.
Conclusions:
- Trypsin stability is highly dependent on pH and temperature.
- Distinct inactivation pathways, including reversible denaturation and irreversible hydrolysis/denaturation, are identified.
- Quantitative equations accurately describe trypsin inactivation kinetics under various conditions.
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