SOLUTION NMR Experimental Data

Experimental Details
Sample Conditions
Sample Contents1 mM protein, 5 mM CaCl2, 10 mM d4-immidazole
Ionic Strength5 mM CaCl2
Temperature (K)298
Experiment(s):3D_15N-separated_NOESY (100 ms), HNHB (chi restraints), HSQC-NOESY-HSQC (tm = 200 ms / perdeuterated protein), HNCACB (TALOS restraints from HN,Ca, Cb shifts ), HNCO (Talos C' shifts), 3D-15N sep TOCSY (Talos Ha shifts)
Sample Contents1 mM protein, 5 mM CaCl2, 10 mM d4-immidazole
Solvent99.9% D2O
Ionic Strength5 mM CaCl2
Temperature (K)298
Experiment(s):3D-13C separated NOESY (tm = 125 ms) and isotope exchange experiments to derive H-bond restraints
Spectrometer Information
Manufacturer Model Field Strength
Varian INOVA 600.0
NMR Refinement
Method Torsion angle dynamics (Dyana 1.5) followed by simulated annealing (X-Plor 3.851)
Details Hydrogen bond restraints were assigned based on protection from solvent exchange, and consistency of hydrogen bonds with preliminary structures. Backbone phi and psi dihedral restraints were obtained from 1Ha, 13Ca, 13Cb, 13C and 15N chemical shifts using the program TALOS (Cornilescu et al., 1993). Side-chain chi1 restraints were from 3D HNHB data, in conjunction with HN-HBETA 2/HN-HBETA 3 and HALPHA-HBETA 2/HALPHA-HBETA 3 NOE intensity ratios. These data were also used to obtain stereospecific assignments for the C-BETA protons of 37 residues. NOEs involving the remainder of prochiral groups with non-degenerate chemical shifts were treated as ambiguous with respect to stereospecific assignments, and represented as 1/^-1/6 sums using XPLOR 3.851 (Brunger, 1992). Initial structures calculated with this approach, were used to identify sites in which one of the stereospecific assignments was more consistent with the remaining distance and dihedral restraints. This enabled stereospecific assignment of a further 13 methylene groups, and 13 valine and leucine prochiral methyl groups. For the final NMR calculations, 400 random conformations were subjected to restrained torsion angle dynamics with the program Dyana 1.5 (Guentert et al., 1997). The 40 structures with the smallest Dyana target functions were refined with a published simulated annealing protocol (Nilges et al., 1991), using the program XPLOR 3.851 (Brunger, 1992). The 15 lowest-energy simulated annealing structures with no distance or dihedral violations larger than 4 were kept for analysis.
NMR Ensemble Information
Conformer Selection Criteria structures with the lowest energy
Conformers Calculated Total Number 400
Conformers Submitted Total Number 15
Representative Model Choice Rationale
1 closest to the average
Additional NMR Experimental Information
1 sample for 15N HSQC-NOESY 15N HSQC was 2H/13C/15N labeled.
Computation: NMR Software
# Classification Software Name Author
1 data analysis FELIX 2000? accelerys
2 refinement X-PLOR 3.851 Brunger
3 structure solution DYANA 1.5 Gntert