1RZS

Solution structure of P22 Cro

SOLUTION NMR

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NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D NOESY	6 mM P22 Cro, 50 mM sodium phosphate buffer, 90% H2O, 10% D2O	90% H2O/10% D2O	50 mM sodium phosphate	6.4	ambient	293
2	HNHA	3.5 mM P22 Cro U-15N, 50 mM sodium phosphate buffer, 90% H2O, 10% D2O	90% H2O/10% D2O	50 mM sodium phosphate	6.4	ambient	293
3	HNHB	3.5 mM P22 Cro U-15N, 50 mM sodium phosphate buffer, 90% H2O, 10% D2O	90% H2O/10% D2O	50 mM sodium phosphate	6.4	ambient	293
4	3D_15N-separated_NOESY	3.5 mM P22 Cro U-15N, 50 mM sodium phosphate buffer, 90% H2O, 10% D2O	90% H2O/10% D2O	50 mM sodium phosphate	6.4	ambient	293
5	3D_13C-separated_NOESY	2.75 mM P22 Cro U-15N, 13C, 50 mM sodium phosphate buffer, 90% H2O, 10% D2O	90% H2O/10% D2O	50 mM sodium phosphate	6.4	ambient	293
6	hydrogen exchange	3.5 mM P22 Cro U-15N, 50 mM sodium phosphate buffer	100% D2O	50 mM sodium phosphate	6.4	ambient	293

NMR Spectrometer Information
Spectrometer	Manufacturer	Model	Field Strength
1	Bruker	DRX	600

NMR Refinement
Method	Details	Software
simulated annealing	30 structures were calculated using 916 NOE-derived distance restraints, 10 hydrogen bond distance restraints, 41 phi angle restraints and 5 chi1 angle restraints. 23 of 30 calculated structures were initially accepted based on no distance restraint violations greater than 0.4 angstroms and no angle restraint violations greater than 5 degrees. Of the 23, 2 were eliminated for having significantly higher energy than the others, leaving 21 structures in the final ensemble. The ordered region of the structure includes residues 1-57. Pairwise RMSDs for the ordered region were 0.53 A (backbone atoms) and 1.29 A (all heavy atoms). None of the backbone angles in the ordered region of any ensemble member fell outside the most favorable and additionally allowed regions of a Ramachandran plot.	XwinNMR

NMR Ensemble Information
Conformer Selection Criteria	agreement with distance and angle restraints; two structures were also eliminated due to high energy
Conformers Calculated Total Number	30
Conformers Submitted Total Number	21
Representative Model	1 (closest to the average)

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	collection	XwinNMR	3.1	Bruker
2	processing	NMRPipe		F. Delaglio et al
3	data analysis	NMRView	4.1.3	B. Johnson
4	structure solution	CNS	1.1	A. Brunger et al
5	refinement	CNS	1.1	A. Brunger et al