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Thioesterase enzyme families: Functions, structures, and mechanisms
Benjamin T Caswell1, Caio C de Carvalho1, Hung Nguyen2
1Department of Chemical and Materials Engineering, University of Nevada, Reno, Reno, Nevada, USA.
Protein Science : a Publication of the Protein Society
|December 18, 2021
Summary
This study classifies thioesterase enzymes into 35 families, enabling prediction of structures and functions for uncharacterized proteins. This aids understanding of diverse biochemical pathways, including fatty acid synthesis.
Area of Science:
- Biochemistry
- Enzymology
- Structural Biology
Background:
- Thioesterases are crucial enzymes hydrolyzing thioester bonds in vital biochemical pathways like fatty acid synthesis.
- Understanding thioesterase function, structure, and mechanism is essential for numerous biological processes.
Purpose of the Study:
- To update and classify thioesterase enzyme families based on sequence similarity.
- To enable prediction of tertiary structures, catalytic residues, and mechanisms for uncharacterized thioesterases.
Main Methods:
- Classification of thioesterases into 35 families using sequence similarity.
- Analysis of experimentally characterized enzymes with resolved tertiary structures.
- Phylogenetic analysis of thioesterases with two main structural folds.
- Tertiary structure superimposition for catalytic residue prediction.
Main Results:
- Established 35 distinct thioesterase families, each with at least one experimentally characterized member.
- Most families include enzymes with resolved crystal structures.
- Phylogenetic analysis revealed evolutionary patterns (convergent and divergent) in thioesterases.
- Identified catalytic residues through structure-based predictions.
Conclusions:
- Family classification provides a framework for inferring properties of uncharacterized thioesterases.
- Structural and phylogenetic analyses offer insights into thioesterase evolution and function.
- This classification facilitates broader understanding and research in enzymology and related fields.
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