1IRA

COMPLEX OF THE INTERLEUKIN-1 RECEPTOR WITH THE INTERLEUKIN-1 RECEPTOR ANTAGONIST (IL1RA)

X-RAY DIFFRACTION

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Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1ILR	IL1RA STRUCTURE (PDB ENTRY 1ILR) AND TRUNCATED CD4 DOMAIN (PDB ENTRY 2CD4)
experimental model	PDB	2CD4	IL1RA STRUCTURE (PDB ENTRY 1ILR) AND TRUNCATED CD4 DOMAIN (PDB ENTRY 2CD4)

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	7		THE COMPLEX OF THE IL-1 RECEPTOR WITH THE ANTAGONIST WAS PREPARED BY MIXING A SOLUTION OF IL-1 RECEPTOR IN 50 MM TRIS (PH 7.5) AND 150 MM NACL WITH A SOLUTION OF IL1RA IN THE SAME BUFFER. THE COMPLEX WAS CRYSTALLIZED USING THE HANGING DROP METHOD. THE DROPS WERE PREPARED BY MIXING 4 UL OF THE PROTEIN SOLUTION WITH 1 UL OF RESERVOIR SOLUTION, CONTAINING 30% (W/V) PEG 3350, 400 MM MGCL2 IN 100 MM MOPS BUFFER (PH 7.0)., vapor diffusion - hanging drop

Crystal Properties
Matthews coefficient	Solvent content
2.7	54

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 47.2	α = 90
b = 84.6	β = 90
c = 140.2	γ = 90

Symmetry
Space Group	P 21 21 21

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	296	AREA DETECTOR	SIEMENS	COLLIMATOR	1994-09-19	M

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	ROTATING ANODE	MACSCIENCE M18X

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Sym 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	2.7	60	97.2	0.06		4.7		15631

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R-Sym I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	2.7	2.8	85.3		0.325		3.1

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	MIR + MOLECULAR REPLACEMENT	THROUGHOUT	IL1RA STRUCTURE (PDB ENTRY 1ILR) AND TRUNCATED CD4 DOMAIN (PDB ENTRY 2CD4)	2.7	8	15012		97.6	0.213	0.213	0.314	RANDOM	45.2

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
x_dihedral_angle_d	26.5
x_scangle_it	17.7
x_mcangle_it	11.5
x_scbond_it	8.3
x_mcbond_it	5.4
x_angle_deg	1.2
x_improper_angle_d	1
x_bond_d	0.004
x_bond_d_na
x_bond_d_prot
x_angle_d
x_angle_d_na
x_angle_d_prot
x_angle_deg_na
x_angle_deg_prot
x_dihedral_angle_d_na
x_dihedral_angle_d_prot
x_improper_angle_d_na
x_improper_angle_d_prot

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	3638
Nucleic Acid Atoms
Solvent Atoms	86
Heterogen Atoms	56

Software

Software
Software Name	Purpose
XDS	data scaling
XSCALE	data scaling
SQUASH	phasing
X-PLOR	model building
X-PLOR	refinement
XDS	data reduction
X-PLOR3.1	phasing