Sensitivity enhancement of homonuclear multidimensional NMR correlations for labile sites in proteins, polysaccharides and nucleic acids
Mihajlo Novakovic, Eriks Kupce, Andreas Oxenfarth, Marcos D. Battistel, Daron I. Freedberg, Harald Schwalbe, Lucio Frydman
Received Date: 7th May 20
Multidimensional TOCSY and NOESY lie at the foundation of NMR in chemistry and biophysics. Limited efficiencies are an intrinsic downside of these methods, particularly when targeting labile sites. This study demonstrates that the decoherence imparted on these protons through solvent exchanges can, when suitably manipulated, lead to dramatic sensitivity gains per unit time. To achieve this a priori selected frequencies are encoded according to Hadamard recipes, while concurrently subject to looped inversion or saturation procedures. Suitable processing then leads to protein, oligosaccharide and nucleic acid cross-peak enhancements of ≈200-600%, in measurements that are >10-fold faster than conventional counterparts. These TOCSY/NOESY gains are achieved at all fields but benefit considerably from the resolution and longer T1s provided by ultrahigh fields, as corroborated by numerous GHz experiments. The efficiency underlying the three-way polarization transfer interplay occurring in these experiments between water, labile and non-labile protons is analyzed, and extensions are discussed.
Read in full at arXiv.
This is an abstract of a preprint hosted on an independent third party site. It has not been peer reviewed but is currently under consideration at Nature Communications.