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Updated: Jul 2, 2025
11:08
A Facile Protocol to Generate Site-Specifically Acetylated Proteins in Escherichia Coli
Published on: December 9, 2017
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Evolution and variation in amide aminoacyl-tRNA synthesis.
Alexander M Lewis1, Trevor Fallon1, Georgia A Dittemore1
1Chemistry Department, Skidmore College, Saratoga Springs, New York, USA.
IUBMB Life
|February 23, 2024
Summary
Life uses indirect pathways to synthesize asparagine and glutamine amino acids for protein synthesis, involving specific enzymes and tRNA complexes called transamidosomes. These ancient routes persist in many organisms, potentially aiding stress adaptation.
Area of Science:
- Biochemistry
- Molecular Biology
- Evolutionary Biology
Background:
- Asparagine and glutamine are essential amide amino acids for protein synthesis.
- Direct synthesis pathways evolved later, but indirect routes persist in many life forms.
Purpose of the Study:
- To investigate the evolution and function of indirect pathways for asparagine and glutamine synthesis.
- To understand the role of these pathways in translational fidelity and stress response.
Main Methods:
- Analysis of aminoacyl-tRNA synthetases and tRNA-dependent amidotransferases.
- Examination of enzyme-tRNA complexes (transamidosomes).
- Comparative genomics and evolutionary analysis.
Main Results:
- Indirect pathways utilize non-discriminating synthetases and amidotransferases (GatCAB, GatDE).
- Transamidosomes maintain translational fidelity.
- Indirect pathways are retained in bacteria, archaea, and eukaryotic organelles, showing significant variation.
Conclusions:
- Indirect synthesis routes for asparagine and glutamine are ancient and conserved.
- These pathways may offer adaptive advantages, including stress response via altered protein synthesis fidelity.
- Further research is needed to clarify the interplay of factors influencing pathway retention versus direct synthesis acquisition.
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