Chemo-enzymatic synthesis of site-specific isotopically labeled nucleotides for use in NMR resonance assignment, dynamics and structural characterizations

Longhini, Andrew P.; LeBlanc, Regan M.; Becette, Owen; Salguero, Carolina; Wunderlich, Christoph H.; Johnson, Bruce A.; D'Souza, Victoria M.; Kreutz, Christoph; Dayie, T. Kwaku

In contrast, NMR spectroscopy can probe dynamic fluctuations directly over a wide range of timescales. Unfortunately, NMR suffers from both narrow chemical shift dispersion and rapid signal decay, exacerbated by direct one-bond and multi-bond spin-spin couplings. The former leads to spectral crowding and the spin-spin couplings can lead to decreased spectral resolution and inaccurate mea-e52 Nucleic Acids Research, 2016, Vol. 44, No. 6 PAGE 2 OF 10 surements of 13 C relaxation rates such as longitudinal relaxation rates (R 1 ), transverse relaxation rates (R 2 ), and heteronuclear Overhauser effect (hNOE) (11) (12) (13) . Furthermore, these problems become more pronounced as the size of the RNA increases: the spectral quality deteriorates because of increased line broadening.