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Updated: May 27, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Solution NMR evidence for symmetry in functionally or crystallographically asymmetric homodimers
Raquel Godoy-Ruiz1, Anna Krejcirikova, D Travis Gallagher
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Abstract:
A recurrent theme of many structural studies of homo-oligomeric protein systems is concerned with verification that the conformation observed in a crystal represents the functionally relevant structure. An asymmetric conformation adopted by two chemically identical subunits in homo-oligomers can represent an intrinsic property of a protein or be an artifact induced by crystal packing forces. Solution NMR studies can distinguish between these two possibilities. Using methyl-based NMR spectroscopy, we provide evidence for symmetry in the absence of ligands in several homodimeric proteins that are either asymmetric functionally and/or adopt different conformations of the two subunits in available X-ray structures.
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