Experiment: 1RL5

NMR structure with tightly bound water molecule of cytotoxin I from Naja oxiana in aqueous solution (major form)

SOLUTION NMR

NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D NOESY	20mM Cytotoxin I, 50mM KCl, H2O	KCl: 50mM, H2O	50 mM	6.0	normal	323
2	2D TOCSY	20mM Cytotoxin I, 50mM KCl, H2O	KCl: 50mM, H2O	50 mM	6.0	normal	323
3	DQF-COSY	20mM Cytotoxin I, 50mM KCl, H2O	KCl: 50mM, H2O	50 mM	6.0	normal	323
4	2D NOESY	20mM Cytotoxin I, 50mM KCl, D2O	KCl: 50mM, D2O	50 mM	6.0	normal	323
5	2D TOCSY	20mM Cytotoxin I, 50mM KCl, D2O	KCl: 50mM, D2O	50 mM	6.0	normal	323
6	DQF-COSY	20mM Cytotoxin I, 50mM KCl, D2O	KCl: 50mM, D2O	50 mM	6.0	normal	323

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

NMR Refinement
Method	Details	Software
torsion angle dynamics	478 NOE-derived constraints, 202 angular constraints, 186 constraints for 31 hydrogen bonds, 24 constraints for 4 SS-bonds	XwinNMR

NMR Ensemble Information
Conformer Selection Criteria	target function
Conformers Calculated Total Number	400
Conformers Submitted Total Number	20
Representative Model	1 (lowest energy)

Additional NMR Experimental Information
Details	Cytotoxin I major and minor conformational states (in ratio of 6:1) in aqueous solution, corresponding to trans and cis val7-pro8 peptide bond conformations, were established via NMR spectra analysis. Here is the obtained major structure of cytotoxin I. The presented at HETATM section HOH in each model are tightly bound water molecules (with longer than for bulk water lifetimes nearby protein), reaveled by NMR approach. The principle of apportionment of these water molecules differs from that in crystal structures, for which the water molecules being at the proximity to protein are indicated.

Additional NMR Experimental Information

Details

Cytotoxin I major and minor conformational states (in ratio of 6:1) in aqueous solution, corresponding to trans and cis val7-pro8 peptide bond conformations, were established via NMR spectra analysis. Here is the obtained major structure of cytotoxin I. The presented at HETATM section HOH in each model are tightly bound water molecules (with longer than for bulk water lifetimes nearby protein), reaveled by NMR approach. The principle of apportionment of these water molecules differs from that in crystal structures, for which the water molecules being at the proximity to protein are indicated.

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	collection	XwinNMR	3.1.a
2	processing	XwinNMR	3.1.a
3	data analysis	XEASY	1.2.11	Bartels. C.
4	structure solution	CYANA	1.0.6	Guntert, P.
5	processing	NMRPipe	April 12, 2001	Delagio, F.
6	data analysis	ACME	2001.085.20.47	Delagio, F.
7	refinement	CYANA	1.0.6	Guntert, P.

1RL5 | pdb_00001rl5

NMR structure with tightly bound water molecule of cytotoxin I from Naja oxiana in aqueous solution (major form)