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Updated: May 19, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Determination of H(N),H (α) and H (N),C' coupling constants in (13)C, (15)N-labeled proteins
R Weisemann1, H Rüterjans, H Schwalbe
1Institut für Biophysikalische Chemie, Universität Frankfurt, Marie-Curie-Strasse 11, D-60439, Frankfurt, Germany.
Abstract:
Sensitive three-dimensional NMR experiments, based on the E.COSY principle, are presented for the measurement of the (3)J(H(N),H(α)) and (3)J(H(N),C') coupling constants in uniformly (13)C- and (15)N-labeled proteins. They employ gradient coherence selection in combination with the sensitivity enhancement method in HSQC-type spectra (Cavanagh et al., 1991; Palmer et al., 1991). In most cases, the two measured coupling constants unambiguously define the ϕ-angle for protein structure determination. The method is applied to uniformly (13)C, (15)N-labeled ribonuclease T(1).
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