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Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions
Published on: April 4, 2014
Theozymes and compuzymes: theoretical models for biological catalysis
D J Tantillo1, J Chen, K N Houk
1Department of Chemistry and Biochemistry University of California 405 Hilgard Avenue Los Angeles CA 90095-1569 USA.
Current Opinion in Chemical Biology
|January 23, 1999
Summary
Theoretical enzymes called theozymes are computed to stabilize transition states, enabling quantitative assessment of catalytic function. This approach has elucidated mechanisms in various enzyme- and antibody-catalyzed reactions.
Area of Science:
- Biochemistry
- Computational Chemistry
- Enzymology
Background:
- Enzymes accelerate reactions by stabilizing the transition state.
- Understanding transition-state stabilization is key to elucidating catalytic mechanisms.
- Theoretical enzymes (theozymes) offer a computational approach to study this stabilization.
Purpose of the Study:
- To define theozymes as theoretical enzymes optimized for transition-state stabilization.
- To enable quantitative assessment of catalytic function using theozymes.
- To apply theozyme computation to elucidate reaction mechanisms.
Main Methods:
- Theozyme construction via computation of optimal geometry for functional group stabilization of transition states.
- Application of theozyme methodology to diverse reaction types.
- Analysis of specific enzymes including orotodine monophosphate decarboxylase, HIV protease, and ribonucleotide reductase.
Main Results:
- Theozyme computation provides a method for quantitative assessment of catalytic function.
- Elucidation of the role of transition-state stabilization in various reactions.
- Insights into mechanisms of hydroxyepoxide cyclizations, eliminations, decarboxylations, hydrolyses, and pericyclic/radical reactions.
Conclusions:
- Theozymes are valuable theoretical tools for understanding enzyme catalysis.
- Computational modeling of transition-state stabilization aids in mechanistic studies.
- This approach is applicable across a broad range of enzymatic reactions.
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