2N4N

NMR structure for a 3-stranded parallel beta-sheet

SOLUTION NMR

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NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D 1H-1H COSY	2 mM protein_1, 2.5 mM acetic acid	90% H2O/10% D2O		3.8	ambient	277
2	2D 1H-1H TOCSY	2 mM protein_1, 2.5 mM acetic acid	90% H2O/10% D2O		3.8	ambient	277
3	2D 1H-1H ROESY	2 mM protein_1, 2.5 mM acetic acid	90% H2O/10% D2O		3.8	ambient	277

NMR Spectrometer Information
Spectrometer	Manufacturer	Model	Field Strength
1	Varian	INOVA	600

NMR Refinement
Method	Details	Software
simulated annealing		X-PLOR NIH

NMR Ensemble Information
Conformer Selection Criteria	structures with the lowest energy
Conformers Calculated Total Number	100
Conformers Submitted Total Number	10
Representative Model	1 (lowest energy)

Additional NMR Experimental Information

Details

The authors state that the structures of these peptides in solution are more dynamic than are typical of well-ordered globular proteins such that the ROE intensities represent averages over multiple conformers. However, the authors make the simplifying assumption of there being a single set of structures. One result of this assumption is that reported clash scores are poorer than those typical of standard PDB structures. Warnings about residues that 'are not properly linked' and 'missing atoms' occur where there are non-natural residues and reversals in the chain directions, and there are no real problems with these stretches.

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	structure solution	X-PLOR NIH	2.35	Schwieters, Kuszewski, Tjandra and Clore
2	refinement	X-PLOR NIH	2.35	Schwieters, Kuszewski, Tjandra and Clore