8CWK

Fab arm of antibodies 4G1-C2 and 10G4 bound to CoV-2 receptor binding domain (RBD)

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP		293	Equal volume (2 uL) of protein solution (approx 5 mg/mL, in 25 mM Tris (pH 8.0), 200 mM NaCl) was mixed with an equal volume of well solution comprising 200 mM sodium citrate, 100 mM Bis-Tris-Propane (pH 7.4), 18% PEG3350). For cryoprotection the crystal was swum briefly (5-10 sec) in well solution doped with glycerol to a final concentration of ~25%.

Crystal Properties
Matthews coefficient	Solvent content
3.27	62.42

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 133.155	α = 90
b = 99.343	β = 108.63
c = 124.957	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 EIGER X 16M		2021-10-21	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	AUSTRALIAN SYNCHROTRON BEAMLINE MX2	0.9536	Australian Synchrotron	MX2

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	2.368	45.8	99.3	0.092	0.101	0.041	0.997	10.9	5.9		62334			53.77

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	2.37	2.43	95.3		1.029	1.127	0.455	0.698		5.8

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	R-Free	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	generic Fab and RBD	2.368	43.235	1.34	62313	3116	99.16	0.1882	0.1863	0.2232	58.7074

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	7.985
f_angle_d	0.813
f_chiral_restr	0.05
f_bond_d	0.005
f_plane_restr	0.005

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	8072
Nucleic Acid Atoms
Solvent Atoms	177
Heterogen Atoms	64

Software

Software
Software Name	Purpose
PHENIX	refinement
XDS	data reduction
Aimless	data scaling
PHASER	phasing
PDB_EXTRACT	data extraction

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), 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 R01GM133198.