Structural information from NMR secondary chemical shifts of peptide alpha C-H protons in proteins.
The secondary chemical shift experienced by the 1H-NMR resonances of the alpha C-H protons in proteins can be correlated with their backbone torsional angles psi, which dictate the orientation of the alpha C-H proton to the adjacent carbonyl group. It is shown that alpha C-H protons present in beta-sheet regions experience downfield secondary shifts, whereas those in alpha-helix regions experience upfield secondary shifts. The predictive use of this correlation in assignment studies is illustrated for the calcium-binding protein paravalbumin, for which a crystal structure is available, and troponin C, for which no crystallographic data are available.
D000595:Amino Acid Sequence; D000818:Animals; D002135:Calcium-Binding Proteins; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008433:Mathematics; D009113:Muramidase; D010455:Peptides; D011487:Protein Conformation; D011506:Proteins; D014359:Trypsin Inhibitor, Kazal Pancreatic
D002135:Calcium-Binding Proteins; D010455:Peptides; D011506:Proteins; D014359:Trypsin Inhibitor, Kazal Pancreatic; D009113:Muramidase