A suite of novel (5,3)D G2FT triple resonance NMR experiments encoding highly resolved 5D spectral information is presented for sequential resonance assignment of proteins exhibiting high chemical shift degeneracy. Efficient resonance assignment is achieved by separate joint sampling of (i) chemical shifts which solely serve to provide increased resolution and (ii) shifts which also provide seq...

We have evaluated the ability of nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopies to describe the difference in the folding propensities of two structurally highly similar cyclic β-hairpins, comparing the outcome to that of molecular dynamics simulations. NAMFIS-type NMR ensemble analysis and CD spectroscopy were observed to accurately describe the consequence of alte...

Elucidating the structure of complex molecules is difficult at low magnetic fields due to the overlap of different peak multiplets and second-order coupling effects. This is even more challenging for rigid molecules with small chemical shift differences and with prochiral centers. Since low-field NMR spectroscopy is sometimes presumed as restricted to the analysis of only small and simple molec...

Aqueous mixtures of formaldehyde and glutathione react to form a variety of cyclized adducts in addition to S-hydroxymethylglutathione. The adducts are in labile equilibrium with each other and are not readily separated. The structures of two of the other major adducts were determined by concerted application of 13C-1H two-dimensional chemical-shift correlation, fast-atom-bombardment mass spect...

Novel 1D and multidimensional solid-state NMR (SSNMR) methods using very fast magic-angle spinning (VFMAS) (spinning speed > 20 kHz) for performing 13C high-resolution SSNMR of paramagnetic organometallic complexes are discussed. VFMAS removes a majority of 13C-1H and 1H-1H dipolar couplings, which are often difficult to remove by RF pulse techniques in paramagnetic complexes because of large p...

Pyridoxal 5’.phosphate labeled to the extent of 90%’ with 13C in the 4’ (aldehyde) and 5’ (methylene) positions has been synthesized. 13C NMR spectra of this material and of natural abundance pyridoxal 5’.phosphate are reported, as well as r3C NMR spectra of the Schiff base formed by reaction of pyridoxal 5’.phosphate with n-butylamine, the secondary amine formed by reduction of this Schiff bas...

Proton-enhanced 13C nuclear magnetic resonance is used to obtain signals from labeled cholesterols in lecithin dispersions. The [26-(13)C]cholesterol resonance indicates that the aliphatic tail of the molecule undergoes reorientation fast enough to average completely the chemical shift anisotropy. In contrast, [4-(13)C]cholesterol signals are characteristic of limited anisotropic reorientation....