4R8I

High Resolution Structure of a Mirror-Image RNA Oligonucleotide Aptamer in Complex with the Chemokine CCL2

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	5.5	277	After thorough optimization of crystallization conditions needle shaped crystals (approx. 300x50x50um) could be obtained by mixing 1uL of the NOX-E36-CCL2 complex (in 20 mM HEPES pH 7.4, 100 mM NaCl, 5 mM KCl, 1 mM MgCl2, 1 mM CaCl2) with 1uL of a solution containing 40 mM Na cacodylate pH 5.5, 12 mM spermine tetrahydrochloride, 40 mM LiCl, 80 mM SrCl2 and 20 mM MgCl2 and subsequent vapor-diffusion equilibration against 1 mL of reservoir (35% (v/v) MPD, 5 mM KCl, 1 mM MgCl2 and 1 mM CaCl2). Crystals used for data collection grew within three weeks at 277K. VAPOR DIFFUSION, HANGING DROP, temperature 277K

Crystal Properties
Matthews coefficient	Solvent content
2.38	48.38

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 108.912	α = 90
b = 108.912	β = 90
c = 34.812	γ = 90

Symmetry
Space Group	P 43 21 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	PIXEL	DECTRIS PILATUS 6M		2013-11-14	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	EMBL/DESY, HAMBURG BEAMLINE X13	0.978	EMBL/DESY, Hamburg	X13

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (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	2.05	100	99.2				24915	-3		36.4

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	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	SAD	THROUGHOUT	2.05	77.01	12058	1348	97.9	0.20504	0.20003	0.24971	RANDOM	32.728

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]
0.21			0.21		-0.41

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	30.662
r_dihedral_angle_4_deg	25.514
r_dihedral_angle_3_deg	14.378
r_dihedral_angle_1_deg	5.36
r_long_range_B_refined	5.024
r_mcangle_it	3.633
r_mcbond_it	2.098
r_angle_refined_deg	1.609
r_scbond_it	1.536
r_chiral_restr	0.074
r_bond_refined_d	0.011
r_gen_planes_refined	0.006

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	544
Nucleic Acid Atoms	853
Solvent Atoms	111
Heterogen Atoms	7

Software

Software
Software Name	Purpose
MxCuBE	data collection
PHENIX	model building
REFMAC	refinement
XDS	data reduction
XDS	data scaling
PHENIX	phasing