MELD-accelerated molecular dynamics help determine amyloid fibril structures

Area of Science:

• Biophysics
• Structural Biology
• Computational Chemistry

Background:

• Determining the structures of protein fibrils, such as amyloids, presents significant challenges.
• Traditional Molecular Dynamics (MD) modeling is often impractical for large multi-molecular systems like fibrils.

Purpose of the Study:

• To demonstrate the capability of MELD accelerated MD (MELD x MD) in predicting amyloid structures from limited experimental data.
• To validate the accuracy of MELD x MD predictions against known fibril structures.

Main Methods:

• Utilized MELD accelerated MD (MELD x MD) simulations.
• Employed Nuclear Magnetic Resonance (NMR) and Solid State NMR (SSNMR) data for long-chain fibril predictions.
• Used limited restraints information, including strand directions, for short-chain fibril predictions.

Main Results:

• Accurately predicted five long-chain amyloid fibril structures using NMR and SSNMR data.
• Successfully predicted ten short-chain amyloid fibril structures with more limited restraints.
• The study validated predictions against available structure data.

Conclusions:

• MELD x MD is a powerful and accurate method for predicting amyloid structures from limited experimental data.
• This physical approach holds promise for elucidating mechanical properties, conformational ensembles, and relative stabilities beyond structure determination.