Parametric sensitivity analysis of avian pancreatic polypeptide (APP)

Area of Science:

• Computational chemistry
• Biophysics
• Molecular dynamics

Background:

• Classical force fields are essential for biomolecular simulations.
• Identifying critical force field parameters is key to understanding molecular properties.

Purpose of the Study:

• To apply sensitivity analysis to avian pancreatic polypeptide (APP).
• To determine how partial charges and solvation parameters affect APP's equilibrium structure and free energy.

Main Methods:

• Utilized molecular dynamics simulations with the OPLS/Amber force field.
• Employed a continuum model for solvation energy calculations.
• Performed sensitivity analysis to identify impactful parameters.

Main Results:

• Pinpointed specific force field parameters with the greatest impact on APP's equilibrium structure (moments of inertia) and free energy.
• Visualized atomic sensitivities to illustrate interaction patterns governing protein stability.
• Electrostatic interactions were identified as more dominant than atomic solvation parameters.

Conclusions:

• Sensitivity analysis is effective for identifying key parameters in biomolecular simulations.
• Electrostatic interactions play a more significant role in avian pancreatic polypeptide stability compared to modeled solvation effects.