Residual methyl protonation in perdeuterated proteins for multi-dimensional correlation experiments in MAS solid-state NMR spectroscopy.
NMR studies involving perdeuterated proteins focus in general on exchangeable amide protons. However, non-exchangeable sites contain as well a small amount of protons as the employed precursors for protein biosynthesis are not completely proton depleted. The degree of methyl group protonation is in the order of 9% for CD2H using >97% deuterium enriched glucose. We show in this manuscript that this small amount of residual protonation is sufficient to perform 2D and 3D MAS solid-state NMR experiments. In particular, we suggest a HCCH-TOBSY type experiment which we successfully employ to assign the methyl resonances in aliphatic side chains in a perdeuterated sample of the SH3 domain of chicken alpha-spectrin.
Agarwal
Vipin
V
Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Campus Berlin-Buch, Robert-Rössle-Strase 10, D-13125 Berlin, Germany.
Reif
Bernd
B
D000577:Amides / Q000737:chemistry*; D003903:Deuterium / Q000737:chemistry*; D007553:Isotope Labeling / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011506:Proteins / Q000032:analysis* / Q000737:chemistry*; D011522:Protons; D013048:Specimen Handling / Q000379:methods; D013223:Statistics as Topic
D000577:Amides; D011506:Proteins; D011522:Protons; D003903:Deuterium