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Published on: November 21, 2017
Measurement of small scalar and dipolar couplings in purine and pyrimidine bases
1Masaryk University, Faculty of Science, National Centre for Biomolecular Research, Brno, Czech Republic.
Abstract:
A suite of spin-state-selective excitation (S3E) NMR experiments for the measurements of small one-bond (13C-13C, 15N-13C) and two-bond (1H-13C, 1H-15N) coupling constants in 13C,15N labeled purine and pyrimidine bases is presented. The incorporation of band-selective shaped pulses, elimination of the cross talk between alpha and beta sub-spectra, and accuracy and precision of the proposed approach are discussed. Merits of using S3E rather than alpha/beta-half-filter are demonstrated using results obtained on isotopically labeled DNA oligonucleotides.
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