Suppression of diagonal peaks in TROSY-type 1H NMR NOESY spectra of 15N-labeled proteins

A novel method for suppression of diagonal peaks in the amide region of NOESY NMR spectra of N-15-labeled proteins is presented. The method is particularly useful for larger proteins at high magnetic fields where interference between dipolar and chemical shift anisotropy relaxation mechanisms results in large TROSY effects, i.e., large differences in H-1(N) Linewidths depending on the spin state of attached N-15 nuclei. In this limit the new TROSY NOESY method does not compromise sensitivity, It is demonstrated using a perdeuterated N-15-labeled protein sample, Neural Cell Adhesion Molecule 213-308 (NCAM) from rat, in H2O at 800 MHz. (C) 1999 Academic Press.