SOLUTION NMR Experimental Data


Experimental Details
Sample Conditions
Spectrometer Information
Manufacturer Model Field Strength
VARIAN UNITY 500 500.0
NMR Refinement
Method AB INITIO - SIMULATED ANNEALING
Details THE STRUCTURE WAS DETERMINED USING 756 DISTANCE RESTRAINTS, 52 DIHEDRAL ANGLE RESTRAINTS AND 22 HYDROGEN BOND RESTRAINTS. THE HYDROGEN BOND RESTRAINTS WERE USED ONLY IN THE LAST STEP OF REFINEMENT. 50 STRUCTURES WERE CALCULATED AND REFINED USING AB INITIO SIMULATED ANNEALING PROTOCOL FOR X-PLOR (1). ALL FORCE CONSTANTS AND POTENTIALS WERE SET TO THE DEFAULT (PROTOCOL) VALUES EXCEPT FOR THE VAN DER WAALS' RADII SCALE FACTOR ("REPEL"), WHICH WAS DECREASED TO 0.80 INSTEAD OF 0.75 DURING THE FINAL COOLING STAGES IN THE REFINEMENT. THIS RESULTS IN MORE REASONABLE BACKBONE CONFORMATION AND SOMEWHAT HIGHER X-PLOR TOTAL ENERGIES. CENTER AVERAGING PSEUDOATOM CORRECTION WAS USED FOR ALL DISTANCE RESTRAINT S(2). ON THE BASIS OF X-PLOR TOTAL ENERGY 42 LOWEST ENERGY STRUCTURES WERE SELECTED. THE AVERAGE AND MINIMIZED STRUCTURE WAS CALCULATED BY AVERAGING SUPERIMPOSED STRUCTURES IN THE ENSEMBLE AND THEN ENERGY MINIMIZING THE AVERAGE STRUCTURE. THE POTENTIALS AND CONSTANTS USED IN THE ENERGY MINIMIZATION WERE THE SAME FOR THE AVERAGE STRUCTURE AND THE ENSEMBLE STRUCTURES.
NMR Ensemble Information
Conformer Selection Criteria MINIMIZED AVERAGE STRUCTURE BASED ON 42 LOWEST ENERGY STRUCTURES
Conformers Calculated Total Number 50
Conformers Submitted Total Number 1
Computation: NMR Software
# Classification Software Name Author
1 structure solution X-PLOR V.3.851 V.3.851 n/a
2 structure solution ANSIG V.3.2 V.3.2 n/a
3 structure solution VNMR 4.3 AND 5.2 n/a
4 refinement X-PLOR 3.851 BRUNGER