3RDX

Crystal structure of ligand-free R7-2 streptavidin

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP	4.5	298	0.1 M Na acetate, pH 4.5, 3 M sodium chloride, VAPOR DIFFUSION, SITTING DROP, temperature 298K

Crystal Properties
Matthews coefficient	Solvent content
2.14	42.55

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 79.25	α = 90
b = 81.64	β = 90
c = 84.537	γ = 90

Symmetry
Space Group	C 2 2 21

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	100	CCD	ADSC QUANTUM 315		2010-06-30	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	NSLS BEAMLINE X29A	1.075	NSLS	X29A

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	2.1	50	99.9	0.099	7.4	6.3		16282

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)
1	2.1	2.14	99.6		0.818		5.6	795

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	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	PDB ENTRY 3RDU	2.101	19.81	16197	817	99.36	0.2156	0.2125	0.2777	RANDOM	22.1929

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]
-0.04			-0.02		0.07

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	27.242
r_dihedral_angle_3_deg	16.005
r_dihedral_angle_4_deg	14.594
r_scbond_it	7.558
r_dihedral_angle_1_deg	7.189
r_mcangle_it	4.006
r_angle_refined_deg	1.385
r_rigid_bond_restr	1.36
r_scangle_it	1.325
r_mcbond_it	1.277
r_chiral_restr	0.098
r_bond_refined_d	0.012
r_gen_planes_refined	0.004

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1819
Nucleic Acid Atoms
Solvent Atoms	109
Heterogen Atoms	6

Software

Software
Software Name	Purpose
SCALEPACK	data scaling
PHASER	phasing
REFMAC	refinement
PDB_EXTRACT	data extraction
CBASS	data collection
HKL-2000	data reduction