1N0C
Stability of cyclic beta-hairpins: Asymmetric contibutions from side chains of hydrogen bonded cross-strand residue pair
SOLUTION NMR
NMR Experiment | ||||||||
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Experiment | Type | Sample Contents | Solvent | Ionic Strength | pH | Pressure | Temperature (K) | Spectrometer |
1 | DQF-COSY | 5 mM peptide, unbuffered | 90% H2O/10% D2O | 0 | 5.0 | 1 atm | 298 | |
2 | 2D TOCSY | 5 mM peptide, unbuffered | 90% H2O/10% D2O | 0 | 5.0 | 1 atm | 298 | |
3 | 2D ROESY | 5 mM peptide, unbuffered | 90% H2O/10% D2O | 0 | 5.0 | 1 atm | 298 | |
4 | 2D ROESY | 5 mM peptide, unbuffered | 100% D2O | 0 | 5.0 | 1 atm | 298 | |
5 | 2D COSY-35 | 5 mM peptide, unbuffered | 100% D2O | 0 | 5.0 | 1 atm | 298 |
NMR Spectrometer Information | |||
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Spectrometer | Manufacturer | Model | Field Strength |
1 | Bruker | DRX | 500 |
NMR Refinement | ||
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Method | Details | Software |
Distance geometry and restrained molecular dynamics with chemical shift refinement | 100 structures were calculated using distance geometry. The 80 structures of lowest penalty function were refined using the Sander module of AMBER (v6.0). The calculation employed 93 distance restraints, 15 dihedral angle restraints and 37 chemical shift restraints. The 20 structures of lowest violation energy were chosen to represent the structure. There are no violations of the input restraints > 0.1 A or 2 degrees. The rms. difference between calculation and observed chemical shifts is 0.12 ppm. 81% of the backbone geometries are in the most favourable region of the Ramachandran plot. The backbone heavy atom rmsd from the mean structure is 0.29+/-0.08 A. | XwinNMR |
NMR Ensemble Information | |
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Conformer Selection Criteria | structures with the least restraint violations |
Conformers Calculated Total Number | 80 |
Conformers Submitted Total Number | 20 |
Representative Model | 1 (closest to the average,fewest violations) |
Additional NMR Experimental Information | |
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Details | Resonance assignments were made using standard 2D homonuclear techniques |
Computation: NMR Software | ||||
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# | Classification | Version | Software Name | Author |
1 | collection | XwinNMR | v3.1 | bruker |
2 | data analysis | Felix | 980 | accelrys |
3 | structure solution | DGII | 980 | Tim Havel |
4 | refinement | Amber | 6.0 | Case, Kollman et al. |
5 | structure solution | Amber | 6.0 |