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Updated: Aug 13, 2026
05:51
Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase
Published on: December 19, 2011
Evolutionary analysis of aspartate aminotransferases
C S Winefield1, K J Farnden, P H Reynolds
1Department of Biochemistry, University of Otago, Dunedin, New Zealand.
Journal of Molecular Evolution
|April 1, 1995
Summary
A phylogenetic analysis of aspartate aminotransferase (AST) enzymes reveals five distinct evolutionary branches. This study clarifies the evolutionary relationships between bacterial, mitochondrial, cytosolic, and plastid AST isoenzymes across diverse species.
Area of Science:
- Biochemistry
- Evolutionary Biology
- Molecular Biology
Background:
- Aspartate aminotransferase (AST) isoenzymes are crucial enzymes found in both the cytosol and organelles of eukaryotic cells.
- All AST isoenzymes, despite their varied locations, are encoded by the nuclear genome.
Purpose of the Study:
- To conduct a comprehensive phylogenetic analysis of aspartate aminotransferase enzymes.
- To elucidate the evolutionary relationships and distinct groupings of AST isoenzymes across plants, animals, yeast, and bacteria.
Main Methods:
- Phylogenetic analysis was employed to study aspartate aminotransferase sequences.
- Comparative analysis included sequences from diverse organisms such as plants, animals, yeast, and bacteria.
Main Results:
- The phylogenetic analysis identified five distinct evolutionary branches within the aspartate aminotransferase family.
- Mitochondrial AST forms, bacterial AST, and plant and vertebrate cytosolic isoenzymes each clustered into separate groups.
- Plant cytosolic isoenzymes formed a distinct group that included plastid sequences, while yeast ASTs formed separate clades.
Conclusions:
- The study successfully delineated five major evolutionary lineages of aspartate aminotransferase.
- Phylogenetic analysis provides a robust framework for understanding the diversification of AST isoenzymes across the tree of life.
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