8F4F

RT XFEL structure of Photosystem II 500 microseconds after the third illumination at 2.03 Angstrom resolution

X-RAY DIFFRACTION

Serial Crystallography (SX)

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	7RF1

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	BATCH MODE	6.5	298	0.1 M MES pH 6.5, 0.1 M NH4Cl, 35% (w/v) PEG 5000

Crystal Properties
Matthews coefficient	Solvent content
3.21	61.66

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 117.534	α = 90
b = 222.832	β = 90
c = 309.505	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	298	CCD	RAYONIX MX340-HS		2021-07-01	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	FREE ELECTRON LASER	SLAC LCLS BEAMLINE MFX	1.305	SLAC LCLS	MFX

Serial Crystallography

Sample delivery method
Diffraction ID	Description	Sample Delivery Method
1	Drop-on-tape	injection

Measurement
Diffraction ID	Pulse Duration	Pulse Repetition Rate	Focal Spot Size	Pulse Energy	Photons Per Pulse
1	40 (fs)	20	7	9500 (KeV)

Injection
Diffraction ID	Description	Flow Rate	Injector Diameter	Injection Power	Injector Nozzle	Filter Size	Carrier Solvent
1	Acoustic Droplet Ejection	4 (µl/min)	undefined (µm)	acoustic wave			Aqueous buffer

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	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	2.03	31.23	99.92	0.99	3.83	105.5		519407			36.67

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	CC (Half)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	2.03	2.06			0.09	0.36	9.1

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	FREE R-VALUE	7RF1	2.03	31.23	1.33	513905	4559	98.89	0.1996	0.1992	0.2485	41.85

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	17.6351
f_angle_d	1.1588
f_chiral_restr	0.0521
f_bond_d	0.0092
f_plane_restr	0.0079

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	41600
Nucleic Acid Atoms
Solvent Atoms	1792
Heterogen Atoms	8546

Software

Software
Software Name	Purpose
PHENIX	refinement
PDB_EXTRACT	data extraction
cctbx.xfel	data reduction
cctbx.xfel.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 R01GM157729.