4R8I

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

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	EMBL/DESY, HAMBURG BEAMLINE X13
Synchrotron site	EMBL/DESY, Hamburg
Beamline	X13
Temperature [K]	100
Detector technology	PIXEL
Collection date	2013-11-14
Detector	DECTRIS PILATUS 6M
Wavelength(s)	0.978
Spacegroup name	P 43 21 2
Unit cell lengths	108.912, 108.912, 34.812
Unit cell angles	90.00, 90.00, 90.00

Refinement procedure

Resolution	77.010 - 2.050
R-factor	0.20504
Rwork	0.200
R-free	0.24971
Structure solution method	SAD
RMSD bond length	0.011
RMSD bond angle	1.609
Data reduction software	XDS
Data scaling software	XDS
Phasing software	PHENIX
Refinement software	REFMAC (5.8.0073)

Data quality characteristics

	Overall
Low resolution limit [Å]	100.000
High resolution limit [Å]	2.050
Number of reflections	24915
Completeness [%]	99.2

Crystallization Conditions

crystal 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