phosaa14SB and phosaa19SB: Updated Amber Force Field Parameters for Phosphorylated Amino Acids

Area of Science:

• Biochemistry
• Computational Biology
• Structural Biology

Background:

• Post-translational modifications, such as phosphorylation, are critical for cellular regulation.
• Molecular simulations are essential for studying protein dynamics and function.
• Existing Amber force fields lack accurate parameters for phosphorylated amino acids.

Purpose of the Study:

• To develop accurate dihedral parameters for phosphorylated amino acids within the Amber ff14SB framework.
• To enhance the computational modeling of proteins containing phosphorylated residues.
• To provide compatible parameter files for both ff14SB and ff19SB Amber models.

Main Methods:

• Quantum mechanics (QM) calculations were used to train dihedral parameters for phosphorylated amino acid side chains.
• Parameters were trained against QM reference data using the ff14SB approach.
• Validated against experimental data to ensure accuracy.

Main Results:

• Developed and validated new dihedral parameters for common phosphorylated amino acids.
• Created library and parameter files compatible with Amber ff14SB and ff19SB.
• Demonstrated improved accuracy in simulating phosphorylated proteins.

Conclusions:

• The new parameters significantly improve the ability to model phosphorylated amino acids in molecular dynamics simulations.
• These advancements will facilitate more accurate computational studies of proteins with these vital post-translational modifications.
• The provided parameter files enhance the utility of Amber for studying phosphoproteomes.