3BX7

Engineered Human Lipocalin 2 (LCN2) in Complex with the Extracellular Domain of Human CTLA-4

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1I85	PDB ENTRY 1I85 chain C, PDB ENTRY 1DFV chain B
experimental model	PDB	1DFV	PDB ENTRY 1I85 chain C, PDB ENTRY 1DFV chain B

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP	8.4	293.15	1.4 M Na-malonate, pH 8.4, VAPOR DIFFUSION, SITTING DROP, temperature 293.15K

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 120.706	α = 90
b = 120.706	β = 90
c = 82.957	γ = 120

Symmetry
Space Group	P 32 2 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	MARMOSAIC 225 mm CCD	mirror	2006-10-31	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	BESSY BEAMLINE 14.1	0.95373	BESSY	14.1

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	2.1	25	98.9	4.9	30	8.6		40987

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)
	2.1	2.18	96.8		41.9	3.3	8.1

Refinement

Statistics
Diffraction ID	Structure Solution Method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Work	R-Free	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	PDB ENTRY 1I85 chain C, PDB ENTRY 1DFV chain B	2.1	20	40457	2036	98.8	0.209	0.226	39.06

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]
5.048	0.47		5.048		-10.097

RMS Deviations
Key	Refinement Restraint Deviation
c_scangle_it	3.144
c_mcangle_it	2.251
c_scbond_it	2.098
c_mcbond_it	1.399

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2287
Nucleic Acid Atoms
Solvent Atoms	186
Heterogen Atoms

Software

Software
Software Name	Purpose
CNS	refinement
PDB_EXTRACT	data extraction
HKL-2000	data collection
HKL-2000	data reduction
HKL-2000	data scaling
PHASER	phasing

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.