2K67

NMR solution structure of modified DNA containing imidazole nucleosides at acidic pH

SOLUTION NMR

NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	2D 1H-1H NOESY	0.5 mM DIH DNA 17-mer, 120 mM sodium perchlorate	100% D2O	120 mM	4.7	ambient	298
2	2D 1H-1H TOCSY	0.5 mM DIH DNA 17-mer, 120 mM sodium perchlorate	100% D2O	120 mM	4.7	ambient	298
3	2D 1H-13C HSQC	0.5 mM DIH DNA 17-mer, 120 mM sodium perchlorate	100% D2O	120 mM	4.7	ambient	298
4	2D 1H-1H NOESY	0.5 mM DIH DNA 17-mer, 120 mM sodium perchlorate	90% H2O/10% D2O	120 mM	4.7	ambient	278

NMR Spectrometer Information
Spectrometer	Manufacturer	Model	Field Strength
1	Bruker	Avance	700

NMR Refinement
Method	Details	Software
torsion angle dynamics, simulated annealing		TOPSPIN

NMR Ensemble Information
Conformer Selection Criteria	structures with the lowest energy
Conformers Calculated Total Number	200
Conformers Submitted Total Number	20
Representative Model	1 (lowest energy)

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	processing	TOPSPIN	1.3, 2.0, 2.1	Bruker Biospin
2	chemical shift assignment	SPARKY	3.1	Goddard
3	data analysis	SPARKY	3.1	Goddard
4	peak picking	SPARKY	3.1	Goddard
5	structure solution	DYANA	1.5	Guntert, Braun and Wuthrich
6	refinement	X-PLOR_NIH	2.15	Schwieters, Kuszewski, Tjandra and Clore

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), 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.