2VXT

Crystal structure of human IL-18 complexed to murine reference antibody 125-2H Fab

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	8.5	277	IL-18 AND 125-2H FAB WERE MIXED (1:3 MASS RATIO), INCUBATED OVERNIGHT AT 277 K, PURIFIED BY MONOQ ANION EXCHANGE CHROMATOGRAPHY, AND CONCENTRATED TO 10 MG/ML. THE COMPLEX WAS CRYSTALLIZED BY HANGING DROP VAPOR DIFFUSION BY MIXING COMPLEX (1.5 MICROLITERS [UL]) WITH 1.8 UL OF RESERVOIR SOLUTION (30% PEG 4000, 100 MM TRIS, PH 8.5, 0.2 M MGCL2) AND 0.3 UL OF 300 MM SULFO-BETAINE 201, AND SUSPENDING THE DROP OVER THE RESERVOIR AT 291 K. ROD-LIKE CRYSTALS APPEARED WITHIN ONE WEEK.

Crystal Properties
Matthews coefficient	Solvent content
2.2	44.1

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 44.345	α = 90
b = 62.435	β = 100.39
c = 104.734	γ = 90

Symmetry
Space Group	P 1 21 1

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	MARRESEARCH	MIRRORS	2003-04-29	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	APS BEAMLINE 32-ID		APS	32-ID

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	1.49	50	94.8	0.06	10.4	3.5		86865		2	21

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	1.49	1.54	56.6		0.35	2.3	2.1

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 1FNS	1.49	31.16	82477	4364	95.5	0.164	0.162	0.196	RANDOM	17.54

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]
0.36		0.84	-0.33		0.28

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	35.698
r_dihedral_angle_4_deg	14.176
r_dihedral_angle_3_deg	12.001
r_dihedral_angle_1_deg	6.85
r_scangle_it	3.508
r_scbond_it	2.562
r_angle_refined_deg	1.662
r_mcangle_it	1.522
r_mcbond_it	1.277
r_angle_other_deg	0.92
r_symmetry_vdw_other	0.235
r_nbd_refined	0.219
r_nbd_other	0.199
r_symmetry_hbond_refined	0.188
r_nbtor_refined	0.178
r_symmetry_vdw_refined	0.164
r_xyhbond_nbd_refined	0.136
r_chiral_restr	0.103
r_nbtor_other	0.086
r_bond_refined_d	0.012
r_gen_planes_refined	0.008
r_gen_planes_other	0.002
r_bond_other_d	0.001
r_xyhbond_nbd_other
r_metal_ion_refined
r_metal_ion_other
r_symmetry_hbond_other
r_symmetry_metal_ion_refined
r_symmetry_metal_ion_other
r_mcbond_other
r_mcangle_other
r_scbond_other
r_scangle_other
r_long_range_B_refined
r_long_range_B_other
r_rigid_bond_restr
r_sphericity_free
r_sphericity_bonded

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	4485
Nucleic Acid Atoms
Solvent Atoms	593
Heterogen Atoms	3

Software

Software
Software Name	Purpose
REFMAC	refinement
HKL-2000	data reduction
SCALEPACK	data scaling
AMoRE	phasing