2KEI

Refined Solution Structure of a Dimer of LAC repressor DNA-Binding domain complexed to its natural operator O1

SOLUTION NMR

NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	3D 1H-13C NOESY	2 mM DNA (5'-D(DGPDAPDAPDTPDTPDGPDTPDGPDAPDGPDCPDGPDGPDAPDTPDAPDAPDCPDAPDAPDTPDTPDT)-3'), 2 mM DNA (5'-D(PDAPDAPDAPDTPDTPDGPDTPDTPDAPDTPDCPDCPDGPDCPDTPDCPDAPDCPDAPDAPDTPDTPDC)-3'), 2 mM Lac headpiece dimer, 10% D2O, 10 mM potassium phosphate, 20 mM potassium chloride	90% H2O/10% D2O	0.03	6	ambient	315
2	3D 1H-15N NOESY	2 mM DNA (5'-D(DGPDAPDAPDTPDTPDGPDTPDGPDAPDGPDCPDGPDGPDAPDTPDAPDAPDCPDAPDAPDTPDTPDT)-3'), 2 mM DNA (5'-D(PDAPDAPDAPDTPDTPDGPDTPDTPDAPDTPDCPDCPDGPDCPDTPDCPDAPDCPDAPDAPDTPDTPDC)-3'), 2 mM Lac headpiece dimer, 10% D2O, 10 mM potassium phosphate, 20 mM potassium chloride	90% H2O/10% D2O	0.03	6	ambient	315
3	2D 1H-1H NOESY	2 mM DNA (5'-D(DGPDAPDAPDTPDTPDGPDTPDGPDAPDGPDCPDGPDGPDAPDTPDAPDAPDCPDAPDAPDTPDTPDT)-3'), 2 mM DNA (5'-D(PDAPDAPDAPDTPDTPDGPDTPDTPDAPDTPDCPDCPDGPDCPDTPDCPDAPDCPDAPDAPDTPDTPDC)-3'), 2 mM Lac headpiece dimer, 10% D2O, 10 mM potassium phosphate, 20 mM potassium chloride	90% H2O/10% D2O	0.03	6	ambient	315

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

NMR Refinement
Method	Details	Software
simulated annealing		CNS

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	refinement	CNS	1.2	Brunger, Adams, Clore, Gros, Nilges and Read
2	chemical shift assignment	XwinNMR		Bruker Biospin
3	processing	NMRPipe		Delaglio, Grzesiek, Vuister, Zhu, Pfeifer and Bax
4	refinement	HADDOCK	2.1	Dominguez, Boelens, Bonvin

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 R01GM157729.