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Optimization of Synthetic Proteins: Identification of Interpositional Dependencies Indicating Structurally and/or Functionally Linked Residues
Published on: July 14, 2015
Structural and functional implications of sequence repeats in fibrous proteins
1Institute of Fundamental Sciences, Massey University, Palmerston North 5301, New Zealand.
Advances in Protein Chemistry
|April 20, 2005
Summary
Nature uses a limited set of protein structural motifs, which can be classified into five distinct groups based on their sequence conservation and length. This classification aids in understanding protein structure and function.
Area of Science:
- Protein bioinformatics
- Structural biology
- Molecular evolution
Background:
- Increasingly large protein sequences reveal a finite repertoire of structural-functional motifs.
- These motifs exhibit diverse arrangements, including tandem repeats and disordered patterns.
- Motif sizes vary significantly across orders of magnitude.
Purpose of the Study:
- To classify protein sequence repeats based on their characteristics.
- To identify distinct categories of structural-functional motifs within protein sequences.
- To provide examples from fibrous and associated proteins for each category.
Main Methods:
- Analysis of amino acid sequences of large proteins.
- Classification of sequence repeats based on character, length, and conservation.
- Comparative analysis of motif properties.
Main Results:
- Identification of five distinct groups of protein sequence repeats (Type A-E).
- Type A: Fixed length, absolutely conserved (>99%).
- Type B: Fixed length, conserved at some positions.
- Type C: Fixed length, conserved character at some positions.
- Type D: Nonintegral lengths.
- Type E: Variable lengths within species, maintaining structural form related to function.
- Examples drawn from fibrous and associated proteins.
Conclusions:
- Protein sequences are built from a finite set of recurring structural-functional motifs.
- A five-category classification system effectively describes the diversity of these repeats.
- Understanding motif classification is crucial for deciphering protein structure-function relationships.
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