6WCO

Structure of SARS main protease bound to inhibitor X47

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	APS BEAMLINE 21-ID-G
Synchrotron site	APS
Beamline	21-ID-G
Temperature [K]	100
Detector technology	CCD
Collection date	2020-02-01
Detector	MARMOSAIC 300 mm CCD
Wavelength(s)	0.988
Spacegroup name	C 1 2 1
Unit cell lengths	108.763, 81.896, 53.672
Unit cell angles	90.00, 103.86, 90.00

Refinement procedure

Resolution	25.960 - 1.480
R-factor	0.1696
Rwork	0.169
R-free	0.19440
Structure solution method	MOLECULAR REPLACEMENT
Starting model (for MR)	6w79
RMSD bond length	0.006
RMSD bond angle	0.909
Data reduction software	HKL-2000
Data scaling software	SCALEPACK
Phasing software	PHENIX
Refinement software	PHENIX (1.13_2998)

Data quality characteristics

	Overall	Outer shell
Low resolution limit [Å]	90.000	1.510
High resolution limit [Å]	1.480	1.480
Rmeas	0.063	0.668
Rpim	0.029	0.312
Number of reflections	75870	3773
<I/σ(I)>	39.6	2.02
Completeness [%]	99.6	99.3
Redundancy	4.7	4.3
CC(1/2)		0.869

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, HANGING DROP	6	278	The SARS-3CLpro:47 a inhibitor complex were co-crystallized using the hanging-drop, vapor-diffusion method by setting up 3 uL drops that were formed by adding 1 uL of purified SARS-3CLpro (10 mg/mL) that had been incubated for three hours with a 3 molar excess of the of compound 47, and 2 uL of reservoir solution: 3 mM DTT, 50 mM MES pH 6.0, 40 mM KCl, 1% MPD, and 5% PEG-10K. Protein crystallization plates were set up at 4 C and protein crystals appeared 24 hours after setting up crystallization plates. Crystals were harvested with a nylon loop and then quickly swiped through the same mother-liquor solution supplemented with 15% MPD.