7QKA | pdb_00007qka

Crystal structure of SARS-CoV-2 Main Protease in complex with covalently bound GC376

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	7AR6

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION	7.5	291	Co-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.

Crystal Properties
Matthews coefficient	Solvent content
1.97	37.53

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 113.675	α = 90
b = 53.356	β = 102.511
c = 44.994	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 EIGER2 X 16M		2021-08-14	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	PETRA III, DESY BEAMLINE P11	1.033	PETRA III, DESY	P11

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)	Redundancy	Number Reflections (All)	Number Reflections (Observed)	Observed Criterion Sigma (F)	Observed Criterion Sigma (I)	B (Isotropic) From Wilson Plot
1	1.8	48.09	98.89	0.04322	0.04674	0.01761	1	23.4	6.9		24372			29.34

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)	Redundancy	Number Unique Reflections (All)
1	1.8	1.864	98.22		0.53	0.5756	0.2213	0.9	3.05	6.6

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work (Depositor)	R-Work (DCC)	R-Free (Depositor)	R-Free (DCC)	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	FREE R-VALUE	7AR6	1.8	48.09	1.35	24367	2000	98.87	0.1667	0.163	0.16	0.2072	0.21	36.95

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
f_dihedral_angle_d	20.6308
f_angle_d	1.081
f_chiral_restr	0.0657
f_bond_d	0.0128
f_plane_restr	0.0092

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2358
Nucleic Acid Atoms
Solvent Atoms	224
Heterogen Atoms	41

Software

Software
Software Name	Purpose
PHENIX	refinement
Coot	model building
XDS	data reduction
XDS	data scaling
PHENIX	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.