Exclusively Heteronuclear NMR Experiments to Obtain Structural and Dynamic Information on Proteins

Provided that C-13-detected NMR experiments are either preferable or complementary to H-1 detection, we report here tools to determine C ''-C', C'-N, and C ''-H '' residual dipolar couplings on the basis of the CON experiment. The coupling constants determined on ubiquitin are consistent with the subset measured with the H-1-detected HNCO sequences. Since the utilization of residual dipolar couplings may depend on the mobility of the involved nuclei, we also provide tools to measure longitudinal and transverse relaxation rates of N and C'. This new set of experiments is a further development of a whole strategy based on C-13 direct-detection NMR spectroscopy for the study of biological macromolecules.