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Updated: Aug 11, 2026
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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Traditional biomolecular structure determination by NMR spectroscopy allows for major errors
Sander B Nabuurs1, Chris A E M Spronk, Geerten W Vuister
1Center for Molecular and Biomolecular Informatics, Nijmegen Center for Molecular Life Sciences, Radboud University, Nijmegen, Netherlands.
Plos Computational Biology
|February 8, 2006
Summary
Structural genomics aims to determine protein structures. However, this study reveals that nuclear magnetic resonance (NMR) structures often lack quality, necessitating advanced validation tools for reliable comparative modeling.
Area of Science:
- Structural biology
- Computational biology
- Biophysics
Background:
- Structural genomics projects aim to determine diverse protein 3D structures.
- Comparative modeling relies on experimentally determined structures for accuracy.
- High-quality structural data is crucial for homology modeling success.
Purpose of the Study:
- To assess the reliability of experimentally determined protein structures, particularly NMR-derived ones.
- To investigate the quality of structural models used in comparative modeling.
- To highlight the need for improved structure validation methods in structural genomics.
Main Methods:
- Comparative modeling of dynein light chain 2A (DLC2A) using two NMR templates.
- In-depth analysis of NMR structure ensembles and deposited experimental data.
- Systematic evaluation of a large set of recent NMR-derived structure ensembles.
Main Results:
- Two NMR templates for DLC2A, despite high sequence identity, exhibited significantly different folds.
- One of the DLC2A NMR models was identified as largely incorrect after detailed analysis.
- A broader survey revealed numerous flawed NMR structures, indicating a systemic issue.
Conclusions:
- Current quality indicators and experimental data are insufficient for reliable NMR structure evaluation.
- There is an urgent need for integrating sophisticated, per-residue structure validation tools in NMR projects.
- The quality of NMR structures from structural genomics and individual efforts requires critical reassessment.
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