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Updated: Aug 7, 2026
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A Protocol for Computer-Based Protein Structure and Function Prediction
Published on: November 3, 2011
Structural classification of proteins: new superfamilies
1Centre for Protein Engineering, Medical Research Council Centre, Cambridge, UK. agm@mrc-lmb.cam.ac.uk
Current Opinion in Structural Biology
|June 1, 1996
Summary
New protein structures are more likely to resemble existing ones than to be entirely novel. This review covers significant new protein superfamilies, including those with broad biological relevance.
Area of Science:
- Structural biology
- Protein bioinformatics
- Biochemistry
Background:
- Protein structural classification is crucial for understanding protein function and evolution.
- The discovery of new protein structures is accelerating.
- Identifying novel protein folds is becoming increasingly rare.
Purpose of the Study:
- To review newly identified protein superfamilies of general biological interest.
- To highlight the trend that new protein structures often share similarities with known ones.
Main Methods:
- Analysis of protein structural databases.
- Comparative structural analysis.
- Literature review of recently discovered protein families.
Main Results:
- New protein structures are statistically more likely to belong to existing superfamilies than to represent new folds.
- Several significant new superfamilies with broad biological relevance have been identified.
- These include superfamilies related to Sonic hedgehog, macrophage migration inhibitory factor, nuclear transport factor-2, double-stranded RNA binding domain, GroES, the proteasome, ATP-hydrolyzing ligases, and flavoproteins.
Conclusions:
- The majority of newly discovered protein structures exhibit homology to known structures, indicating a convergence in protein fold evolution.
- The identified superfamilies represent important additions to the protein structural repertoire and have implications for various biological processes.
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