Experiment: 2I7Z

GAAA tetraloop receptor complex with associated manganese ions.

SOLUTION NMR

NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D NOESY	1 mM GAAA tetraloop receptor RNA, 10 uM manganese, 12 mM MgCl2 50 mM NaCl; 100% D2O	100% D2O		7.0	ambient	303
2	2D TOCSY	1 mM GAAA tetraloop receptor RNA, 10 uM manganese, 12 mM MgCl2 50 mM NaCl; 100% D2O	100% D2O		7.0	ambient	303
3	2D NOESY	1 mM GAAA tetraloop receptor RNA, 500 uM manganese, 12 mM MgCl2 50 mM NaCl; 100% D2O	100% D2O		7.0	ambient	303
4	2D TOCSY	1 mM GAAA tetraloop receptor RNA, 500 uM manganese, 12 mM MgCl2 50 mM NaCl; 100% D2O	100% D2O		7.0	ambient	303
5	H 1D	1 mM GAAA tetraloop receptor RNA, 500 uM manganese, 12 mM MgCl2 50 mM NaCl	90% H2O/10% D2O		7.0	ambient	283
6	2D NOESY	1 mM GAAA tetraloop receptor RNA, 500 uM manganese, 12 mM MgCl2 50 mM NaCl	90% H2O/10% D2O		7.0	ambient	283

NMR Spectrometer Information
Spectrometer	Manufacturer	Model	Field Strength
1	Bruker	DMX	600
2	Bruker	DMX	750

NMR Refinement
Method	Details	Software
Structures were refined by cooling from 3000 K to 100 K in 58 cycles of restrained Cartesian coordinate space corresponding to a total of 28 ps. The force constant for RDCs was increased from 0.001 to 0.2 kcal mol-1 Hz-2. Five hundred steps of energy minimization using the Powell algorithm followed simulated annealing.		CNS

NMR Ensemble Information
Conformer Selection Criteria	structures with the lowest energy
Conformers Calculated Total Number	100
Conformers Submitted Total Number	20
Representative Model	1 (lowest energy)

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	refinement	CNS	1.0	Brunger A. T. etal
2	refinement	X-PLOR	2.11
3	processing	XwinNMR	2.6
4	data analysis	Sparky	3.111