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Updated: Jul 31, 2026
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Creating and Applying a Reference to Facilitate the Discussion and Classification of Proteins in a Diverse Group
Published on: August 16, 2017
Sequence and structural aspects of functional diversification in class I alpha-mannosidase evolution
I K Jordan1, G R Bishop, D S Gonzalez
1National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
Bioinformatics (Oxford, England)
|October 24, 2001
Summary
Natural selection drove the functional diversification of alpha-mannosidases, with key changes occurring at the protein periphery. This gradual evolution shaped distinct Endoplasmic Reticulum (ER) and Golgi enzyme groups.
Area of Science:
- Biochemistry
- Evolutionary Biology
- Molecular Biology
Background:
- Class I alpha-mannosidases are a diverse family of glycoside hydrolases.
- Phylogenetic analysis identified four distinct groups within this enzyme family.
- Gene duplications contributed to the diversity of these enzymes since early eukaryotic evolution.
Purpose of the Study:
- To investigate the role of natural selection in the divergence of Endoplasmic Reticulum (ER) and Golgi alpha-mannosidases.
- To understand sequence and structural differences between phylogenetically and functionally distinct enzyme groups.
Main Methods:
- Amino acid sequence alignment of the catalytic domain of class I alpha-mannosidases.
- Phylogenetic analysis to identify enzyme groups.
- Comparison of site-specific amino acid variability profiles between ER and Golgi enzyme groups.
Main Results:
- Statistically significant evidence for functional diversification at the sequence level between ER and Golgi groups.
- Identified specific amino acid residues likely responsible for functional divergence.
- Observed that many selected residues are located at the periphery of the catalytic domain, suggesting gradual functional adaptation.
Conclusions:
- Positive selection has driven functional diversification of alpha-mannosidases.
- Peripheral residue changes, influenced by diversifying selection, likely contributed to gradual functional adaptation in ER and Golgi enzyme groups.
- Findings support a Darwinian model of gradual natural selection in enzyme evolution.
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