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Updated: Jul 19, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Calculation of structural behavior of indirect NMR spin-spin couplings in the backbone of nucleic acids
Vladimír Sychrovský1, Zuzana Vokácová, Jirí Sponer
1Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic. bohdan@uochb.cas.cz
Abstract:
Calculated indirect NMR spin-spin coupling constants (J-couplings) between (31)P, (13)C, and (1)H nuclei were related to the backbone torsion angles of nucleic acids (NAs), and it was shown that J-couplings can facilitate accurate and reliable structural interpretation of NMR measurements and help to discriminate between their distinct conformational classes. A proposed stepwise procedure suggests assignment of the J-couplings to torsion angles from the sugar part to the phosphodiester link. Some J-couplings show multidimensional dependence on torsion angles, the most prominent of which is the effect of the sugar pucker. J-couplings were calculated in 16 distinct nucleic acid conformations, two principal double-helical DNAs, B- and A-, the main RNA form, A-RNA, as well as in 13 other RNA conformations. High-level quantum mechanics calculations used a baseless dinucleoside phosphate as a molecular model, and the effect of solvent was included. The predicted J-couplings correlate reliably with available experimental data from the literature.
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