Streamlined Postprocessing of NMR Structures with the Molecular Restrainer: A Universal Tool for High-Quality Protein-Ligand Models and Non-Standard Amino Acid Residues

Area of Science:

• Structural Biology
• Computational Chemistry
• Biophysics

Background:

• Nuclear Magnetic Resonance (NMR) spectroscopy is crucial for determining molecular structures.
• Refining NMR-derived structures is essential for accurate biological interpretation and deposition.
• Existing methods may require extensive parameterization and computational resources.

Purpose of the Study:

• To introduce a novel molecular restrainer tool for energy minimization of NMR-derived structures.
• To enable rapid processing of diverse molecular complexes without custom force field parameterization.
• To enhance the quality and readiness of structures for publication and deposition.

Main Methods:

• Utilizing the Universal Force Field (UFF) for energy minimization.
• Incorporating Nuclear Overhauser Effect (NOE)-derived distance restraints.
• Implementing the tool within the SAMSON molecular design platform (v2024+).
• Postprocessing of structures initially derived from CYANA software.

Main Results:

• Demonstrated significant improvement in structural quality compared to initial CYANA-derived structures.
• Showcased the tool's ability to process various molecules and complexes efficiently.
• Validated the generation of publication-ready protein-ligand complex structures.

Conclusions:

• The molecular restrainer tool offers an efficient and effective method for refining NMR structures.
• It simplifies the process of preparing high-quality structures for deposition in databases like the PDB.
• The tool's adaptability allows for integration with various molecular restraint formats.