1IM7

Solution structure of synthetic cyclic peptide mimicking the loop of HIV-1 gp41 glycoprotein envelope

SOLUTION NMR

NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D NOESY	2mM and 4mM peptide ; 500 ul 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 energy minimisation	50 initial random strucutres were produced using simulated annealing in DYANA software.Refinement was done with 500 steps restrained minimization , 35ps MD in vacuo at 300K for equilibration and 200ps MD under NMR restraints and 750 steps conjugeted gradient EM using DISCOVER module of MSI software.	XwinNMR

NMR Ensemble Information
Conformer Selection Criteria	target function
Conformers Calculated Total Number	50
Conformers Submitted Total Number	1
Representative Model	1 (minimized average structure)

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

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

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.