2HOK

Crystal structure of an E. coli thi-box riboswitch bound to thiamine pyrophosphate, calcium ions

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1		6	295	grown: 28% PEG 2000, 10% w/v sucrose, 0.2 M NH4Cl, 10 mM CaCl2, 50 mM cacodylate pH 6.0; 1.5 mM MgCl2, 0.25 mM TPP, 50 mM KCl, 0.25 mM spermine; cryo: above but 25.7% w/v sucrose; 360 x 50 x 50 um xtal, VAPOR DIFFUSION, HANGING DROP, temperature 295K, pH 6.00

Crystal Properties
Matthews coefficient	Solvent content
2.41	48.86

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 66.3	α = 90
b = 66.3	β = 90
c = 101.6	γ = 120

Symmetry
Space Group	P 32 1 2

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	100	IMAGE PLATE	RIGAKU RAXIS IV		2005-02-11	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	ROTATING ANODE	RIGAKU

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Merge I (Observed)	Net I Over Average Sigma (I)	Redundancy	Number Reflections (All)	Number Reflections (Observed)	Observed Criterion Sigma (F)	Observed Criterion Sigma (I)	B (Isotropic) From Wilson Plot
1	3.2	30	100	0.125	26.8	10.5		4368

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R Merge I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
	3.2	3.31			0.488	8.1	10.5	403

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Resolution (High)	Resolution (Low)	Number Reflections (All)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	3.2	30	4368	4210	428		0.214	0.214	0.291	RANDOM

Temperature Factor Modeling
Anisotropic B[1][1]	Anisotropic B[1][2]	Anisotropic B[1][3]	Anisotropic B[2][2]	Anisotropic B[2][3]	Anisotropic B[3][3]

RMS Deviations
Key	Refinement Restraint Deviation
c_angle_deg	1.27
c_bond_d	0.006
c_bond_d_na
c_bond_d_prot
c_angle_d
c_angle_d_na
c_angle_d_prot
c_angle_deg_na
c_angle_deg_prot
c_dihedral_angle_d
c_dihedral_angle_d_na
c_dihedral_angle_d_prot
c_improper_angle_d
c_improper_angle_d_na
c_improper_angle_d_prot
c_mcbond_it
c_mcangle_it
c_scbond_it
c_scangle_it

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms
Nucleic Acid Atoms	1646
Solvent Atoms	1
Heterogen Atoms	33

Software

Software
Software Name	Purpose
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling
CNS	phasing