7AF0

Structure of SARS-CoV-2 Main Protease bound to Ipidacrine.

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	COUNTER-DIFFUSION		291	Co-crystallization with the compounds was achieved by equilibrating a 6.25 mg/ml protein solution in 20 mM HEPES buffer (pH 7.8) containing 1 mM DTT, 1 mMEDTA, and 150 mM NaCl against a reservoir solution of 100 mM MIB, pH 7.5, containing 25% w/w PEG 1500 and 5% v/v DMSO. Prior to crystallization compound solutions in DMSO were dried onto the wells of SwissCI 96-well plates. To obtain well-diffracting crystals in a reproducible way seeding was applied for crystal growth. Crystals appeared within a few hours and reached their final size after 2 - 3 days. Crystals were manually harvested and flash-frozen in liquid nitrogen for subsequent X-ray diffraction data collection.

Crystal Properties
Matthews coefficient	Solvent content
1.93	36.24

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 112.753	α = 90
b = 52.96	β = 102.9
c = 44.842	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	PIXEL	DECTRIS PILATUS3 6M		2020-04-29	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	PETRA III, DESY BEAMLINE P11	1.0332	PETRA III, DESY	P11

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	CC (Half)	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	1.7	27.49	99.73	0.993	6.05	3.5		28452

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	CC (Half)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	1.7	1.761	99.51		0.764

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	MOLECULAR REPLACEMENT	THROUGHOUT	6YB7	1.7	27.49	27488	956	99.65	0.1792	0.1776	0.225	RANDOM	19.503

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]
1.71		-0.66	0.09		-1.36

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	33.453
r_dihedral_angle_4_deg	18.121
r_dihedral_angle_3_deg	11.876
r_dihedral_angle_1_deg	7.191
r_angle_refined_deg	1.428
r_angle_other_deg	0.522
r_chiral_restr	0.072
r_bond_refined_d	0.011
r_gen_planes_refined	0.008
r_bond_other_d	0.001
r_gen_planes_other	0.001

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2367
Nucleic Acid Atoms
Solvent Atoms	433
Heterogen Atoms	23

Software

Software
Software Name	Purpose
XSCALE	data scaling
REFMAC	refinement
PDB_EXTRACT	data extraction
XDS	data reduction
REFMAC	phasing