Experiment: 3IWM

The octameric SARS-CoV main protease

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	2HOB	PDB ENTRY 2HOB

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	5.5	291	0.2M Sodium chloride, 0.1M Bis-Tris (pH 5.5) and 25% w/v PEG 3350, VAPOR DIFFUSION, HANGING DROP, temperature 291K

Crystal Properties
Matthews coefficient	Solvent content
4.03	69.45

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 161.93	α = 90
b = 161.93	β = 90
c = 166.435	γ = 90

Symmetry
Space Group	P 41 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	100	CCD	ADSC QUANTUM 270		2009-03-21	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	PHOTON FACTORY BEAMLINE BL-17A	1.0000	Photon Factory	BL-17A

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	3.2	50	97	0.155		22.6	37177	33573			97.7

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	3.2	3.3	64.6		0.652		4	2900

Refinement

Statistics
Diffraction ID	Structure Solution Method	Starting model	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (All)	R-Factor (Observed)	R-Work (Depositor)	R-Work (DCC)	R-Free (Depositor)	R-Free (DCC)	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	PDB ENTRY 2HOB	3.2	48.943	1.34	33573	1771	94.13	0.231	0.223	0.2204	0.2153	0.2721	0.2635	random	86.617

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]
9.033			9.033		-4.906

RMS Deviations
Key	Refinement Restraint Deviation
f_dihedral_angle_d	23.541
f_angle_d	1.526
f_chiral_restr	0.104
f_plane_restr	0.021
f_bond_d	0.009

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	9512
Nucleic Acid Atoms
Solvent Atoms
Heterogen Atoms

Software

Software
Software Name	Purpose
HKL-2000	data collection
PHASER	phasing
PHENIX	refinement
HKL-2000	data reduction
HKL-2000	data scaling