1XSX

NMR Structure of Sso10a, a Hyperthermophile DNA-binding Protein with an Extended Anti-parallel Coiled Coil

SOLUTION NMR

NMR Experiment
Experiment	Type	Sample Contents	Solvent	Ionic Strength	pH	Pressure	Temperature (K)	Spectrometer
1	3D_15N-separated_NOESY	25 mg/ml 15N,13C Sso10a, 90% H2O, 10% D2O	90% H2O/10% D2O		5.0	ambient	303
2	3D_13C-separated_NOESY	25 mg/ml 15N,13C Sso10a	100% D2O		5.0	ambient	303
3	3D_12C-filtered_13C-edited_NOESY	25 mg/ml 15N,13C Sso10a	100% D2O		5.0	ambient	303
4	HNHA	25 mg/ml 15N,13C Sso10a, 90% H2O, 10% D2O	90% H2O/10% D2O		5.0	ambient	303
5	2D_HSQC-IPAP	12 mg/ml 15N Sso10a	85% H2O, 10% D20, 5% C12E5/hexanol (r=0.87)		5.0	ambient	308
6	2D_HSQC_T1_T1rho_NOE	12 mg/ml 15N Sso10a, 90% H2O, 10% D2O	90% H2O/10% D2O		5.0	ambient	303

NMR Spectrometer Information
Spectrometer	Manufacturer	Model	Field Strength
1	Varian	INOVA	800
2	Varian	INOVA	500

NMR Refinement
Method	Details	Software
Simulated annealing using cartesion and torsion angle dynamics.	NOE assignments, distance restraint calibrations, and initial structures were made using ARIA 1.2. Final structure refinemnet was done using Xplor-NIH. Restraints consisted of 1231 intrasubunit and 83 intersubunit NOE-derived distances, 144 torsion angles, 60 HNHA coupling constants, 41 H-bonds, 52 dipolar couplings, 54 T1/T2 relaxation ratios, and non-crystallographic dimer symmetry restraints. (Numbers of restraints are per monomer.) Anisotropy tensors were included as variables during refinemnet, with best fit values for the molecular alignment tensor (from RDC's) of Da=16 Hz and rhombicity=0.24, and best fit values for the diffusion anisotropy tensor (from 15N relaxation) of Dpar/Dperp=2.0 and rhombicity=0.05 (and tauC=13.7 ns).	VNMR

NMR Ensemble Information
Conformer Selection Criteria	10 smallest RMSD out of 13 lowest energy
Conformers Calculated Total Number	75
Conformers Submitted Total Number	11
Representative Model	1 (minimized average structure)

Additional NMR Experimental Information
Details	model 1 is an energy minimized average structure. Models 2 through 11 are the 10 best ensemble structures.

Computation: NMR Software
#	Classification	Version	Software Name	Author
1	collection	VNMR	6.1C	Varian Inc.
2	processing	NMRPipe	2004	F. Delaglio
3	data analysis	NMRView	5.2.2	M. Johnson
4	data analysis	ModelFree	4	A. Palmer
5	structure solution	ARIA	1.2	J. Linge, M. Nilges
6	refinement	Xplor-NIH	2.9.6	Brunger, Clore
7	structure solution	Xplor-NIH	2.9.6	Brunger, Clore

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.