COMMUNICATIONS Triple Resonance Solid State NMR Experiments with Reduced Dimensionality Evolution Periods

13 CO ii1 and 15 Ni chemical shifts. The CA N COCA experiment establishes the correlation 13 Cai and 15 COi to 13 Cfiii1 and 15 Nii1 within a single experiment by simultaneous encoding of the 13 Cfii and 15 Ni chemical shifts. This experiment establishes sequential amino acid correlations in close analogy to the solution state HNCA experi- ment. Reduced dimensionality 2D experiments are a practical al- ternative to recording multiple 3D data sets for the purpose of ob- taining sequence-specific resonance assignments of peptides and proteins in the solid state. C ∞ 2001 Academic Press