Three-dimensional NMR spectroscopy of a protein in solution.
The geometric information used to solve three-dimensional (3D) structures of proteins by NMR spectroscopy resides in short (less than 5 A) interproton-distance data. To obtain these distances, the 1H-NMR spectrum must first be assigned using correlation and nuclear Overhauser effect (NOE) experiments to demonstrate through-bond (scalar) and through-space connectivities, respectively. Because the NOE is proportional to r-6, distance information can then be derived. The increased resolution afforded by extending NMR experiments into a second dimension enables one to detect and interpret effects that would not be possible in one dimension owing to extensive spectral overlap and much reduced information. A number of small protein structures have previously been solved in this way. Extending this methodology to larger proteins, however, requires yet an additional improvement in resolution as overlap of cross-peaks in the two-dimensional (2D) NMR spectra present a major barrier to their unambiguous identification. One way of increasing the resolution is to extend the 2D-NMR experiments into a third dimension. We report here the applicability of three-dimensional NMR to macromolecules using the 46-residue protein alpha 1-purothionin as an example.
Oschkinat
H
H
Max-Planck Institut für Biochemie, Martinsried bei München, FRG.
Griesinger
C
C
Kraulis
P J
PJ
Sørensen
O W
OW
Ernst
R R
RR
Gronenborn
A M
AM
Clore
G M
GM
D023181:Antimicrobial Cationic Peptides; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D010940:Plant Proteins; D011487:Protein Conformation; D012984:Software
D023181:Antimicrobial Cationic Peptides; D010940:Plant Proteins; C016085:purothionin