7Z3U

Crystal structure of SARS-CoV-2 Main Protease after incubation with Sulfo-Calpeptin


X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
TypeSourceAccession CodeDetails
experimental modelPDB 6YNQ 

Crystallization

Crystalization Experiments
IDMethodpHTemperatureDetails
1VAPOR DIFFUSION291Co-crystallization with the compound was achieved by equlibrating a 6.25 mg/ml protein solution in 20 mM HEPES buffer (pH 7.8) containing 1 mM DTT, 1mM EDTA, and 150 mM NaCl against a reservoir solution of 100 mM MIB buffer (2:3:3 molar ratio of malonic acid, imidazole, and boric acid), pH 7.5, containing 25% v/v 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 achieve reproducible crystal growth seeding was used. Crystals appeared within a few hours and reached their final size after 2 -3 days. Crystals were manually harvested and flash cooled in liquid nitrogen for subsequent X-ray diffraction data collection.
Crystal Properties
Matthews coefficientSolvent content
2.5451.62

Crystal Data

Unit Cell
Length ( Å )Angle ( ˚ )
a = 67.692α = 90
b = 99.598β = 90
c = 103.261γ = 90
Symmetry
Space GroupP 21 21 21

Diffraction

Diffraction Experiment
ID #Crystal IDScattering TypeData Collection TemperatureDetectorDetector TypeDetailsCollection DateMonochromatorProtocol
11x-ray100PIXELDECTRIS EIGER2 S 16M2021-05-07MSINGLE WAVELENGTH
Radiation Source
ID #SourceTypeWavelength ListSynchrotron SiteBeamline
1SYNCHROTRONPETRA III, DESY BEAMLINE P111.033PETRA III, DESYP11

Data Collection

Overall
ID #Resolution (High)Resolution (Low)Percent Possible (Observed)R Merge I (Observed)Rrim I (All)Rpim I (All)CC (Half)Net I Over Average Sigma (I)RedundancyNumber Reflections (All)Number Reflections (Observed)Observed Criterion Sigma (F)Observed Criterion Sigma (I)B (Isotropic) From Wilson Plot
11.7249.2299.70.1010.10860.0390.99912.547.57468926.42
Highest Resolution Shell
ID #Resolution (High)Resolution (Low)Percent Possible (All)Percent Possible (Observed)R Merge I (Observed)Rrim I (All)Rpim I (All)CC (Half)Mean I Over Sigma (Observed)RedundancyNumber Unique Reflections (All)
11.721.78298.312.1722.3280.82830.5240.957.7

Refinement

Statistics
Diffraction IDStructure Solution MethodCross Validation methodStarting modelResolution (High)Resolution (Low)Cut-off Sigma (F)Number Reflections (Observed)Number Reflections (R-Free)Percent Reflections (Observed)R-Factor (Observed)R-WorkR-FreeMean Isotropic B
X-RAY DIFFRACTIONMOLECULAR REPLACEMENTFREE R-VALUE6YNQ1.7249.221.3374542201099.710.19190.19070.235138.76
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
KeyRefinement Restraint Deviation
f_dihedral_angle_d18.7435
f_angle_d1.2789
f_chiral_restr0.0676
f_bond_d0.013
f_plane_restr0.0092
Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen AtomsNumber
Protein Atoms4642
Nucleic Acid Atoms
Solvent Atoms433
Heterogen Atoms68

Software

Software
Software NamePurpose
PHENIXrefinement
Cootmodel building
XDSdata reduction
XSCALEdata scaling
PHENIXphasing