Comparison of protein secondary structures based on backbone dihedral angles

Area of Science:

• Structural bioinformatics
• Computational biology
• Biophysics

Background:

• Protein secondary structure comparison is crucial for understanding protein function and evolution.
• Existing methods may not fully capture the nuances of structural similarity.
• A need exists for robust and sensitive measures of protein structure comparison.

Purpose of the Study:

• To develop a novel quantitative measure for comparing protein secondary structures.
• To represent protein secondary structures as angle sequences for analysis.
• To evaluate the effectiveness of the proposed method using a dataset of known proteins.

Main Methods:

• Transformation of protein secondary structures into angle sequences.
• Partitioning of the backbone phi, psi-space for representation.
• Evaluation of pairwise sequence distance using symbolic sequence complexity.
• Construction of a similarity tree for 24 proteins from the Protein Data Bank (PDB).

Main Results:

• The proposed angle sequence representation effectively captures structural information.
• The symbolic sequence complexity provides a robust measure of pairwise distance.
• The similarity tree visually represents the relationships between the 24 proteins.
• The method demonstrates a comparable or improved ability to discern structural similarities.

Conclusions:

• The angle sequence approach offers a novel and effective way to compare protein secondary structures.
• This method enhances the quantitative analysis of structural similarities in proteins.
• The developed technique has potential applications in protein classification and function prediction.