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NMR Spectral Alignment Utilizing a CryoEM Motion Correction Algorithm
Colin A Hemme1,2, Owen A Warmuth1, Songlin Wang1
1Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Dr, Madison, Wisconsin 53706, United States.
Analytical Chemistry
|December 15, 2025
Summary
Automated NMR Spectral Alignment (ANSA) software aligns solid-state NMR spectra using image-based cross-correlation. This method overcomes manual alignment limitations, enhancing data rigor and enabling automated processing for complex experiments.
Area of Science:
- Biophysics
- Analytical Chemistry
- Structural Biology
Background:
- Magic-angle spinning (MAS) solid-state NMR (SSNMR) offers high resolution but faces spectral alignment challenges.
- Existing methods lack automation and are subjective, hindering analysis of complex datasets like large proteins.
- Field gradients, temperature variations, and pulse sequence effects cause referencing errors in SSNMR data.
Purpose of the Study:
- To develop an automated spectral alignment method for SSNMR data.
- To address the limitations of manual, subjective peak inspection for spectral referencing.
- To improve the accuracy and reproducibility of SSNMR data processing.
Main Methods:
- Developed Automated NMR Spectral Alignment (ANSA) software.
- Adapted principles from cryo-electron microscopy motion correction for NMR spectra.
- Utilized cross-correlation functions to treat NMR spectra as images for alignment.
Main Results:
- ANSA improved cross-correlation scores from 0.33 to 1.00 in controlled tests.
- Achieved 0.96 correlation in real-world applications with previously misaligned spectra.
- Successfully aligned spectra across various experimental conditions and corrected shifts in long-duration experiments.
Conclusions:
- ANSA provides objective and consistent spectral alignment, enhancing scientific rigor.
- The software improves reproducibility and enables automation of critical NMR data processing steps.
- ANSA is available as an open-source tool for integration into existing NMR workflows.
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