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Updated: Jul 11, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Estimation of 3JHN-Halpha and 3JHalpha-Hbeta coupling constants from heteronuclear TOCSY spectra
Katiuscia Pagano1, Federico Fogolari, Alessandra Corazza
1Dipartimento di Scienze e Tecnologie Biomediche, Università di Udine, Piazzale Kolbe 4, Udine, Italy.
Abstract:
(3)J proton-proton coupling constants bear information on the intervening dihedral angles. Methods have been developed to derive this information from NMR spectra of proteins. Using series expansion of the time dependent density matrix, and exploiting the simple topology of amino acid spin-systems, formulae for estimation of (3)J(HN-Halpha) and (3)J(Halpha-Hbeta) from HSQC-TOCSY spectra are derived. The results obtained on a protein entailing both alpha-helix and beta-sheet secondary structure elements agree very well with J-coupling constants computed from the X-ray structure. The method compares well with existing methods and requires only 2D spectra which would be typically otherwise recorded for structural studies.
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