Simple model for the simulation of peptide folding and aggregation with different sequences.

Area of Science:

• Computational chemistry
• Biophysics
• Protein folding simulations

Background:

• Peptide folding is crucial for protein function.
• Accurate simulation of peptide folding requires sophisticated models.
• Understanding the interplay of different interactions is key.

Purpose of the Study:

• To develop a coarse-grained interaction potential for peptide folding.
• To investigate the influence of hydrophobic and hydrogen bond interactions on peptide self-assembly.
• To reproduce representative features of peptide folding using a simplified model.

Main Methods:

• Development of a coarse-grained model with one interaction bead per amino acid.
• Incorporation of a simple hydrogen bond potential and a reduced amino acid alphabet accounting for hydrophobic interactions.
• Equilibrium simulations at varying temperatures and concentrations.

Main Results:

• Hydrophobic interactions dominate at low concentrations, favoring alpha-helices and beta-sheets.
• Hydrogen bond interactions become more influential at higher concentrations, promoting beta-type aggregates.
• Simulated aggregates retain sequence-specific characteristics.

Conclusions:

• The developed coarse-grained model effectively captures essential peptide folding behaviors.
• Concentration-dependent interactions dictate the formation of specific peptide structures and aggregates.
• The model provides insights into sequence-specific aggregate formation.