AQuaRef: machine learning accelerated quantum refinement of protein structures
Open Access
- 17 October 2025
- journal article
- research article
- Published by Springer Nature in Nature Communications
- Vol. 16 (1) , 1-12
Abstract
Cryo-EM and X-ray crystallography provide crucial experimental data for obtaining atomic-detail models of biomacromolecules. Refining these models relies on library-based stereochemical data, which, in addition to being limited to known chemical entities, do not include meaningful noncovalent interactions. Quantum mechanical (QM) calculations could alleviate these issues but are too expensive for large molecules. Here we present a novel AI-enabled Quantum Refinement (AQuaRef) based on AIMNet2 machine learned interatomic potential (MLIP) mimicking QM at substantially lower computational costs. By refining 41 cryo-EM and 30 X-ray structures, we show that this approach yields atomic models with superior geometric quality compared to standard techniques, while maintaining an equal or better fit to experimental data. Notably, AQuaRef aids in determining proton positions, as illustrated in the challenging case of short hydrogen bonds in the parkinsonism-associated human protein DJ-1 and its bacterial homolog YajL.Keywords
This publication has 78 references indexed in Scilit:
- Balanced basis sets of split valence, triple zeta valence and quadruple zeta valence quality for H to Rn: Design and assessment of accuracyPhysical Chemistry Chemical Physics, 2005
- REFMAC5 dictionary: organization of prior chemical knowledge and guidelines for its useActa Crystallographica Section D Structural Biology, 2004
- Coot: model-building tools for molecular graphicsActa Crystallographica Section D Structural Biology, 2004
- Combined quantum and molecular mechanics calculations on metalloproteinsCurrent Opinion in Chemical Biology, 2003
- Structure validation by Cα geometry: ϕ,ψ and Cβ deviationProteins: Structure, Function, and Bioinformatics, 2003
- Faculty Opinions recommendation of The penultimate rotamer library.2002
- Rfreeand theRfreeratio. II. Calculation of the expected values and variances of cross-validation statistics in macromolecular least-squares refinementActa Crystallographica Section D Structural Biology, 2000
- The Protein Data BankNucleic Acids Research, 2000
- Asparagine and glutamine: using hydrogen atom contacts in the choice of side-chain amide orientation 1 1Edited by J. ThorntonJournal of Molecular Biology, 1999
- Rfreeand theRfreeRatio. I. Derivation of Expected Values of Cross-Validation Residuals Used in Macromolecular Least-Squares RefinementActa Crystallographica Section D Structural Biology, 1998