8IRD

XFEL structure of cyanobacterial photosystem II following two flashes (2F) with a 20-nanosecond delay

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	MICROBATCH	6	293	5.5% PEG1450, 20mM NaCl, 10mM CaCl2, 40mM MgSO4, 20mM Mes BUFFER

Crystal Properties
Matthews coefficient	Solvent content
3.52	65.09

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 125.77	α = 90
b = 231.76	β = 90
c = 288.58	γ = 90

Symmetry
Space Group	P 21 21 21

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	293	CCD	RAYONIX MX300-HS		2020-02-26	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	FREE ELECTRON LASER	SACLA BEAMLINE BL2	1.24	SACLA	BL2

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	CC (Half)	R Split (All)	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	2.3	47.45	100	0.991	0.094	49.7	306.5		370932

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	CC (Half)	R Split (All)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	2.3	2.34			0.543	0.692

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	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	FREE R-VALUE	2.3	19.99	1.34	370932	18655	99.96	0.1444	0.1423	0.1835

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	23.432
f_angle_d	1.301
f_chiral_restr	0.057
f_plane_restr	0.009
f_bond_d	0.008

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	41493
Nucleic Acid Atoms
Solvent Atoms	1823
Heterogen Atoms	9317

Software

Software
Software Name	Purpose
PHENIX	refinement
cctbx.xfel	data reduction
cxi.merge	data scaling
PHASER	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 R01GM133198.