1QX3

Conformational restrictions in the active site of unliganded human caspase-3

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	7.5	294	4-6% PEG 8000, 5-7% isopropanol, pH 7.5, VAPOR DIFFUSION, HANGING DROP, temperature 294K

Crystal Properties
Matthews coefficient	Solvent content
2.52	51.22

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 70.26	α = 90
b = 96.19	β = 90
c = 44.17	γ = 90

Symmetry
Space Group	P 21 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	98	IMAGE PLATE	MARRESEARCH			M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	SSRL BEAMLINE BL7-1	0.9200	SSRL	BL7-1

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	1.9	50	87.5	0.061	13.5	3		21234	2	1	20.5

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	1.9	1.97	78.6		0.318	13.5	3	1848

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (All)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	PDB ENTRY 1CP3	1.9	20	2	21234	19881	970	81.9	0.249	0.278	RANDOM	35.9

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]
7.74			11.92		-19.66

RMS Deviations
Key	Refinement Restraint Deviation
c_dihedral_angle_d	23.5
c_angle_deg	1.2
c_improper_angle_d	0.71
c_bond_d	0.006

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1881
Nucleic Acid Atoms
Solvent Atoms	147
Heterogen Atoms

Software

Software
Software Name	Purpose
MAR345	data collection
SCALEPACK	data scaling
AMoRE	phasing
CNS	refinement

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 R01GM133198.