1D and 2D NMR Techniques for Peptide Structure Elucidation

Nuclear Magnetic Resonance, NMR, Spectroscopy is a powerful technique for determining the three-dimensional structures of peptides in solution. NMR provides detailed information on the local chemical environment of atomic nuclei, making it an ideal method for studying peptide folding, dynamics, and interactions.

One-Dimensional NMR – 1D-NMR

In 1D-NMR, spectra are recorded by observing the resonance of nuclear spins, usually ¹H or ¹³C nuclei, in a magnetic field. This technique provides basic structural information such as chemical shifts, coupling constants, and integrals, which reflect the relative abundances of atomic nuclei in different environments. While 1D-NMR is useful for small peptides, it may lack the resolution needed for more complex structures.¹

Two-Dimensional NMR – 2D-NMR

2D-NMR techniques offer greater resolution and provide insights into peptide structure that cannot be obtained from 1D-NMR alone. Common 2D-NMR methods include correlation spectroscopy, COSY, which identifies spin-spin couplings between nuclei, and nuclear Overhauser effect spectroscopy, NOESY, which provides information on spatial proximity between atoms. These techniques are essential for determining the secondary and tertiary structures of peptides in solution.²

Conclusion

1D and 2D NMR techniques are indispensable for elucidating peptide structure. While 1D-NMR offers basic insights into chemical shifts and couplings, 2D-NMR enables more detailed structural characterization, making it invaluable for studying peptide folding, dynamics, and interactions.

Citations and Links

1. Wüthrich, Kurt. NMR of Proteins and Nucleic Acids. Wiley, 1986.

2. Sattler, Michael, et al. “The Role of NOE in Determining Peptide Structure.” Nature Structural Biology, vol. 4, no. 10, 1997, pp. 726–731. doi:10.1038/nsb1097-726.