1J8Z

Solution structure of beta3 analogue peptide (HCYS) of HIV gp41 600-612 loop.

SOLUTION NMR

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NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D NOESY	2mM peptide in 500ul DMSO-D6	DMSO-D6			ambient	298
2	DQF-COSY	4mM peptide in 500ul DMSO-D6	DMSO-D6			ambient	298
3	TOCSY	4mM peptide in 500ul DMSO-D6	DMSO-D6			ambient	298

NMR Spectrometer Information
Spectrometer	Manufacturer	Model	Field Strength
1	Bruker	AVANCE	400
2	Bruker	AVANCE	600

NMR Refinement
Method	Details	Software
torsion angle dynamics, molecular dynamics, energy minimization.	50 initial random structures were generated using simulated annealing in DYANA software, followed using the DISCOVER module of MSI software, by 500 steps restrained minimization, 35 ps MD in vacuo at 300K, 200ps MD under NMR restraints and 750ps conjugated gradient EM.	XwinNMR

NMR Ensemble Information
Conformer Selection Criteria	target function
Conformers Calculated Total Number	50
Conformers Submitted Total Number	24
Representative Model	1 (lowest energy)

Additional NMR Experimental Information
Details	This structure was determined using standard 2D homonuclear techniques. NOESY experiments were recorded with mixing times from 80ms to 800ms in order to determined the best conditions to avoid spin diffusion.

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	collection	XwinNMR	2.6	Bruker GMBH
2	processing	XwinNMR	2.6	Bruker GMBH
3	data analysis	XEASY	1.2	Bartels C., Xia T., Billeter M., Guentert P. and Wuethrich K., (1995) , J. Biomol. NMR, 5, 1-10
4	structure solution	DYANA	1.5	Guentert P., Mumenthaler C. and Wuethrich K. (1997) J. Mol. Biol., 273, 283-298
5	structure solution	Discover	3	Molecular Simulation Inc. , San Diego
6	refinement	Discover	3	Molecular Simulation Inc. , San Diego