TROSY-type triple-resonance experiments for sequential NMR assignments of large proteins

Transverse relaxation-optimized spectroscopy (TROSY) was implemented in the four triple resonance experiments [N-15,H-1]-TROSY-HN(CO)CA, [N-15,H-1]-TR OSY-HN(CA)CO, [N-15,H-1]-TROSY-HNCACB, and [N-15, H-1]-TROSY-HN(CO)CACB. Co mbined with [N-15,H-1]-TROSY-HNCA and [N-15,H-1]-TROSY-HNCO (Salzmann, M.; Pervushin, K.; Wider, G.; Senn, H. Wuthrich, K. Proc. Natl. Acad. Sci. U.S. A. 1998, 13585-13590) these experiments represent a suite of TROSY-type tri ple resonance experiments that enables sequential backbone assignment of pr oteins. When used with the 23 kDa H-2/C-13/N-15-labeled protein gyrase 23B, a comparison with the corresponding conventional NMR experiments showed, o n average over the entire amino acid sequence, a 3-fold sensitivity gain fo r each of the four experiments. The use of the TROSY principle in triple re sonance experiments thus promises to enable resonance assignments for signi ficantly larger proteins than what is achievable today with the correspondi ng conventional NMR experiments.