Two-dimensional Correlation Spectra Research Articles

Correlation of 13C and 1H chemical shifts in bovine high-density lipoprotein from two-dimensional NMR

Two-dimensional heteronuclear 13C 1H chemical-shift correlation spectra were obtained for bovine high-density lipoprotein (HDL). The 13C and 1H shifts of the lipid components are assigned. No evidence for dynamic equilibration of lipid classes between different structure environments was found at this limited resolution. Heteronuclear correlation spectroscopy can be effectively applied to macromolecular complexes as large as HDLs.

Correlation of proton and nitrogen-15 chemical shifts by multiple quantum NMR

Techniques for the correlation of 1H and 15N chemical shifts based on zero and double quantum NMR are discussed. The indirect determination of nitrogen shifts from the proton signals provides a dramatic gain in sensitivity over direct observation of 15N signals. Examples are given of applications of the methods to samples with natural abundance 15N concentration and to a sample of 0.7 m M 65% 15N enriched tRNA ƒ Met in H 2O. Two-dimensional 15H 15N shift correlation spectra of 0.1 M samples with natural abundance 15N concentration in a 5 mm sample tube can be obtained in measuring times on the order of 1 hr.