Experiment: 1U64

The Solution Structure of d(G3T4G4)2

SOLUTION NMR

NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D NOESY	4mM dG3T4G4 per strand; 90% H2O, 10% D2O, 15mM KCl; pH 5.5	90% H2O/10% D2O	15mM KCl	5.5	ambient	278
2	2D NOESY	4mM dG3T4G4 per strand; 90% H2O, 10% D2O, 15mM KCl; pH 5.5	90% H2O/10% D2O	15mM KCl	5.5	ambient	298
3	PE-COSY	4mM dG3T4G4 per strand; 90% H2O, 10% D2O, 15mM KCl; pH 5.5	90% H2O/10% D2O	15mM KCl	5.5	ambient	298
4	2D TOCSY	4mM dG3T4G4 per strand; 90% H2O, 10% D2O, 15mM KCl; pH 5.5	90% H2O/10% D2O	15mM KCl	5.5	ambient	298

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

NMR Refinement
Method	Details	Software
simulated annealing, energy minimization	414 NOE-derived distance restraints associated with the nonexchangeable and exchangeable protons; 24 hydrogen-bond restraints; 66 torsion angle restraints for sugar moieties. For each of five different initial structures ten simulated annealing calculations at 700 K with NMR restraints using a generalized Born (GB) implicit solvation model were performed for 60 ps. The resulting structures were subjected to energy minimization	VNMR

NMR Ensemble Information
Conformer Selection Criteria	structures with the least restraint violations, structures with the lowest energy
Conformers Calculated Total Number	50
Conformers Submitted Total Number	8
Representative Model	5 (fewest violations, lowest energy)

Additional NMR Experimental Information
Details	This structure was determined using standard 2D homonuclear techniques.

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	collection	VNMR	6.1B	Varian
2	processing	Felix	2000	Accelerys
3	refinement	Amber	7	Kollman, at all