Mass spectrometry assisted assignment of NMR resonances in 15N labeled proteins

Lianmei Feng1, Ron Orlando, James H Prestegard

  • 1Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602, USA.

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Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
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This lesson illustrates the role of deuterium substitution in simplifying the NMR spectrum of compounds comprising labile protons. One method employed is the use of deuterium. Amongst the three isotopes of hydrogen, deuterium (2H) has a nucleus composed of one proton and one neutron. When the D2O solvent is added to a pure dry ethanol solution, its labile proton is substituted with deuterium.
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