Sequential HNCACB and CBCANH protein NMR pulse sequences

The pulse sequences HNCACB and CBCANH correlating side chain C-beta resonan ces with amide resonances in the protein backbone do not distinguish betwee n inter- and intraresidue correlations. The new pulse sequences sequential HNCACB and sequential CBCANH make this distinction by suppressing coherence transfer between C-13(alpha) and N-15 via the one-bond J(NCalpha) coupling so that only the sequential correlations are observed in the spectrum. The experimental results of applying sequential HNCACB in a clean-TROSY-adapte d implementation to the protein Chymotrypsin Inhibitor 2 at 800 MHz are pre sented. (C) 2001 Academic Press.