15N-1H scalar coupling perturbation: an additional probe for measuring structural changes due to ligand binding.
Chemical shift perturbation mapping of backbone amides is one of the most widely employed techniques in biomolecular NMR, providing residue-by-residue information on interaction interfaces, ligand binding, and chemical modification sites, even for samples where poor solubility, short lifetime, or large size precludes more sophisticated experimental approaches. Significant changes can also occur in the amide one-bond (15)N-(1)H scalar coupling constants for glutamine binding protein (GlnBP) due to ligand binding. Like chemical shift perturbations, large changes (>1 Hz) are seen near the site of glutamine binding, though perturbations also occur distant to the site. The coupling constant perturbations correlate with significant structural changes, especially changes in backbone hydrogen bonding. Thus, amide scalar coupling perturbation can serve as an adjunct to chemical shift perturbation, providing additional information on both short-range and longer-range, allosteric structural changes.
Ma
Junhe
J
Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, 50 South Drive, Bethesda, Maryland 20892, USA.
Gruschus
James M
JM
Tjandra
Nico
N
D000577:Amides / Q000737:chemistry*; D001665:Binding Sites; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular; D011522:Protons
D000577:Amides; D008024:Ligands; D009587:Nitrogen Isotopes; D011522:Protons