3D NOESY-TOCSY-HSQC and TOCSY-NOESY-HSQC NMR experiments

From NMR Wiki

Magnetization pathway (TOCSY-NOESY-HSQC): H (ω1) -- TOCSY --> ... -- NOE --> H¹⁵N -- inept --> H¹⁵N (ω2) -- inept --> H (ω3)¹⁵N

In NOESY-TOCSY-HSQC NOESY and TOCSY mixing periods are interchanged.

Both experiments are said to work best in extended β-sheet protein folds, where there is strong HN-CHα vicinal coupling. The two experiments differ in directioinality of correlations. The cited [1] advantage over 3D NOESY-HSQC is presence of sequential HN-HN NOE's for β-sheet proteins.

References

1. MUELLER, L and CAMPBELL-BURK, S and DOMAILLE, P. 15N-correlated three-dimensional relayed NOESY experiments in uniformly 15N-labeled proteins. Journal of magnetic resonance 96(2):408--415, 1992. BibTeX [mu92jmr]