Experiment: 1K43

10 Structure Ensemble of the 14-residue peptide RG-KWTY-NG-ITYE-GR (MBH12)

SOLUTION NMR

NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D ROESY	1 mM Peptide MBH12	90% H2O/10% D2O	0	5.0	ambient	283
2	2D NOESY	1 mM Peptide MBH12	100% D2O	0	5.0	ambient	283
3	2D NOESY	1 mM Peptide MBH12	40% CD3OD, 60% H2O	0	5.0	ambient	283

NMR Spectrometer Information
Spectrometer	Manufacturer	Model	Field Strength
1	Bruker	DRX	500

NMR Refinement
Method	Details	Software
simulated annealing combined with torsion angle dynamics (DYANA)	The structures are based on a total of 70 restraints, 60 are NOE-derived distance constraints and 10 dihedral angle restraints. The pairwise RMSD for residues 3-12 was 0.38 +/- 0.21 A for the backbone and 1.36 +/- 0.35 A for all heavy atoms. The estimated beta-hairpin population of this peptide is 66 +/- 4%. The first and last two residues (RG) are disordered, because they were added just to avoid aggregation. The side chains of Trp4, Tyr6, Ile9 and Tyr11 are interacting in one side of the beta hairpin, forming a hydrophobic cluster. Asn7 at position L1 of the beta-turn is directed outwards from the beta-hairpin, as expected for a type I' beta-turn.	XwinNMR

NMR Ensemble Information
Conformer Selection Criteria	structures with the lowest energy
Conformers Calculated Total Number	50
Conformers Submitted Total Number	10
Representative Model	6 (lower rmsd with respect to mean)

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	collection	XwinNMR	2.6	Bruker
2	data analysis	XwinNMR	2.6	Bruker
3	structure solution	DYANA	1.5	Guntert, P. et al.
4	refinement	GROMOS	96	van Gunsteren