2HOB

Crystal structure of SARS-CoV main protease with authentic N and C-termini in complex with a Michael acceptor N3

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1UK3

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	6	291	2% polyethylene glycol(PEG) 6000, 3% DMSO, 1mM DTT, 0.1M [2-(N-morpholino)ethanesulfonic acid] (Mes) buffer (pH 6.0), with a protein concentration of 5mg/ml. Inhibitor N3 was dissolved in 7.5% PEG 6000, 6% DMSO, and 0.1M Mes (pH 6.0) with a concentration of 10mM (supersaturation). Then, a 3 micro-l aliquot of such solution was added to the drop, and the crystals were soaked for approximately 2-6 days., VAPOR DIFFUSION, HANGING DROP, temperature 291K

Crystal Properties
Matthews coefficient	Solvent content
3.36	63.35

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 108.566	α = 90
b = 81.21	β = 104.48
c = 53.287	γ = 90

Symmetry
Space Group	C 1 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	IMAGE PLATE	MAR scanner 345 mm plate		2006-06-03	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	ROTATING ANODE	RIGAKU	1.5418

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (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	1.95	50	99.6				32068

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	1.95	2.02	97.9

Refinement

Statistics
Diffraction ID	Structure Solution Method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (All)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (All)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	1UK3	1.95	50	32731	29940	2938		0.224	0.205	0.202	0.221	RANDOM

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
c_angle_deg	1.83
c_bond_d	0.015

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2420
Nucleic Acid Atoms
Solvent Atoms	308
Heterogen Atoms

Software

Software
Software Name	Purpose
CNS	refinement
HKL-2000	data reduction
HKL-2000	data scaling
CNS	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.