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Updated: Jan 17, 2026
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Defining Substrate Specificities for Lipase and Phospholipase Candidates
Published on: November 23, 2016
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A method for predicting enzyme substrate specificity residues using homologous sequence information
Seiya Mori1, Teppei Niide1, Yoshihiro Toya1
1Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, The University of Osaka, Osaka, Japan.
Protein Science : a Publication of the Protein Society
|September 25, 2025
Summary
This study introduces a new method to pinpoint crucial amino acid residues influencing enzyme substrate specificity. Experiments validated the approach, successfully altering enzyme function through targeted mutations.
Area of Science:
- Biochemistry
- Structural Biology
- Computational Biology
Background:
- Distinguishing structural from functionally critical amino acid residues in enzymes is a significant challenge.
- Understanding residue function is vital for enzyme mechanism elucidation, drug discovery, and protein engineering.
Purpose of the Study:
- To develop a computational methodology for identifying amino acid residues that determine enzyme substrate specificity.
- To validate the method's efficacy in predicting and experimentally confirming specificity-determining residues.
Main Methods:
- Framing sequence comparison of homologous enzymes as a classification problem, with residues as features.
- Applying the method to enzyme pairs: trypsin/chymotrypsin, adenylyl cyclase/guanylyl cyclase, and lactate dehydrogenase (LDH)/malate dehydrogenase (MDH).
- Experimental validation through site-directed mutagenesis on the LDH/MDH pair.
Main Results:
- Accurate prediction of known specificity-determining residues across tested enzyme pairs.
- Successful experimental alteration of LDH substrate specificity by mutating identified key residues to utilize oxaloacetate.
- Demonstrated maintenance of protein expression levels post-mutation.
Conclusions:
- The developed methodology efficiently identifies residues governing enzyme substrate specificity.
- This approach facilitates enzyme engineering and functional studies.
- The method is accessible via the EZSCAN tool (https://ezscan.pe-tools.com/).
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