J-based 2D homonuclear and heteronuclear correlation in solid-state proteins.
Scalar-based two-dimensional heteronuclear experiments are reported for NCO and NCA chemical shift correlation in the solid state. In conjunction with homonuclear CACO correlation, these experiments form a useful set for tracing connectivities and assigning backbone resonances in solid-state proteins. The applicability of this approach is demonstrated on two proteins, the β 1 immunoglobulin binding domain of protein G at 9.4 T and reassembled thioredoxin at 14.1 T, using different decoupling conditions and MAS frequencies. These constant-time J-based correlation experiments exhibit increased resolution in the indirect dimension owing to homonuclear and heteronuclear decoupling, and because the indirect evolution and transfer periods are combined into a single constant time interval, this increased resolution is not obtained at the cost of sensitivity. These experiments are also shown to be compatible with in-phase anti-phase (IPAP) selection, giving increased resolution in the directly detected dimension.
D000465:Algorithms; D001426:Bacterial Proteins / Q000737:chemistry*; D002247:Carbon Isotopes; D007136:Immunoglobulins / Q000737:chemistry*; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry; D013879:Thioredoxins / Q000737:chemistry*
D001426:Bacterial Proteins; D002247:Carbon Isotopes; C034284:IgG Fc-binding protein, Streptococcus; D007136:Immunoglobulins; D009587:Nitrogen Isotopes; D011994:Recombinant Proteins; D013879:Thioredoxins