Deciphering the shape and deformation of secondary structures through local conformation analysis

Area of Science:

• Structural biology
• Protein dynamics
• Bioinformatics

Background:

• Traditional methods like RMSD and PCA analyze protein deformation globally.
• A local approach is needed to understand variations in secondary structure conformations within different protein regions.

Purpose of the Study:

• To investigate secondary structure shape variations within proteins.
• To analyze protein deformation at interfaces during complexation using a local approach.

Main Methods:

• Utilized a structural alphabet to convert 3D protein structures into sequences of structural letters.
• Analyzed the distribution and transitions of these structural letters across protein surface, core, and interface compartments.

Main Results:

• Secondary structures exhibit distinct local conformations preferred in the surface (curved) versus core (straight) compartments.
• Protein interfaces show a mix of local conformations, influenced by both surface and core preferences.
• Secondary structure deformation upon complexation is strongly correlated with compartment-specific local conformation preferences.

Conclusions:

• A structural alphabet provides a detailed local description of secondary structure shape and deformation in protein surface, core, and interface regions.
• Understanding these induced-fit modifications is vital for identifying functionally constrained regions in proteins.