Assignment strategies in homonuclear three-dimensional sup 1 H NMR spectra of proteins

• Published in: Biochemistry (Easton) Vol. 29:7
• Main Authors: Vuister, G.W., Boelens, R., Padilla, A., Kleywegt, G.J., Kaptein, R.
• Format: Journal Article
• Language: English
• Published: United States 20.02.1990
• Subjects: ALANINES; ALBUMINS; AMINO ACID SEQUENCE; AMINO ACIDS; BARYONS; BASIC BIOLOGICAL SCIENCES; CARBOXYLIC ACIDS; ELEMENTARY PARTICLES; FERMIONS; HADRONS; LEUCINE; MAGNETIC RESONANCE; MOLECULAR STRUCTURE; NMR SPECTRA; NUCLEAR MAGNETIC RESONANCE; NUCLEONS; ORGANIC ACIDS; ORGANIC COMPOUNDS; PROTEINS; PROTONS; RELAXATION; RESONANCE; SPECTRA 550201 > Biochemistry > Tracer Techniques
• ISSN: 0006-2960; 1520-4995
• DOI: 10.1021/bi00459a024

The increase in dimensionality of three-dimensional (3D) NMR greatly enhances the spectral resolution in comparison to 2D NMR. It alleviates the problem of resonance overlap and may extend the range of molecules amenable to structure determination by high-resolution NMR spectroscopy. Here, the authors present strategies for the assignment of protein resonances from homonuclear nonselective 3D NOE-HOHAHA spectra. A notation for connectivities between protons, corresponding to cross peaks in 3D spectra, is introduced. They show how spin systems can be identified by tracing cross-peak patterns in cross sections perpendicular to the three frequency axes. The observable 3D sequential connectivities in proteins are tabulated, and estimates for the relative intensities of the corresponding cross peaks are given for {alpha}-helical and {beta}-sheet conformations. Intensities of the cross peaks in the 3D spectrum of pike III paravalbumin follow the predictions. The sequential-assignment procedure is illustrated for loop regions, extended and {alpha}-helical conformations for the residues Ala 54-Leu 63 of paravalbumin. NOEs that were not previously identified in 2D spectra of paravalbumin due to overlap are found.