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Mass Spectrometry-Based Proteomics Analyses Using the OpenProt Database to Unveil Novel Proteins Translated from Non-Canonical Open Reading Frames
Published on: April 11, 2019
Alternative oxidase: what information can protein sequence comparisons give us?
1Department of Biology, The University of Western Ontario, 1151 Richmond St. N., London, Ontario N6A5B7, Canada. amcdon27@uwo.ca
Physiologia Plantarum
|June 5, 2009
Summary
Alternative oxidase (AOX) sequence analysis reveals conserved amino acids crucial for its function and regulation. This comparative study identifies new potential functional sites in AOX proteins across diverse life forms.
Area of Science:
- Biochemistry
- Molecular Biology
- Evolutionary Biology
Background:
- Alternative oxidase (AOX) is a widespread enzyme found across most kingdoms of life.
- A large number of AOX sequences are available for in-depth analysis.
- Understanding AOX function is vital for various biological processes.
Purpose of the Study:
- To identify conserved amino acids and domains in AOX proteins involved in catalysis, membrane association, and regulation.
- To validate the utility of multiple sequence alignment coupled with structural modeling for AOX research.
- To investigate sequence differences across kingdoms and their functional implications.
Main Methods:
- Multiple sequence alignment of AOX proteins from evolutionarily divergent organisms.
- Comparative analysis of a large dataset of AOX sequences.
- Utilizing structural models of AOX for functional site prediction.
Main Results:
- Confirmed conserved glutamate and histidine residues essential for AOX identification and structural modeling.
- Identified 35 additional conserved amino acids in AOX, with 30 previously uninvestigated.
- Revealed significant sequence differences between kingdoms, suggesting roles for angiosperm-specific domains in dimerization and aplastidic AOX indels in regulation.
Conclusions:
- Multiple sequence alignment is a powerful tool for AOX functional site prediction.
- Numerous novel conserved residues in AOX likely play key roles in quinol terminal oxidase activity and membrane association.
- Further structural determination of AOX will significantly advance research into its diverse functions.
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