Experiment: 6CXK

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP	6.5	293.15	Sitting drop of final volume of 0.8 uL was set up by 1:1 v/v mixing of 15 mg/mL E. coli DHFR working stock with reservoir solution containing 0.1M MES pH 6.5, 27.5% PEG 3350, 0.4M MgCl2. E. coli DHFR working stock was prepared from a 1:1 v/v mixture of 30 mg/ml protein in 20 mM Tris pH 8, 1mM DTT with 50 mM HEPES pH 7.3, 100 mM NaCl. Crystals harvested after 2 weeks growth and cryoprotected with mitegen LV oil before flash freezing in N2.

Crystal Properties
Matthews coefficient	Solvent content
1.78	31.02

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 33.698	α = 90
b = 51.525	β = 90
c = 77.421	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	100	CCD	RAYONIX MX-225	Diamond(111)	2017-11-30	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	APS BEAMLINE 31-ID	0.97931	APS	31-ID

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Merge I (Observed)	Rrim 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	1.108	30.949	97.9	0.067	0.073	0.999	13.44	6.255		53265			11.47

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R Merge I (Observed)	Rrim I (All)	CC (Half)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	1.108	1.18	87.3		0.861	1.051	0.571	1.16	2.804

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	7DFR	1.108	30.949	1.34	53202	1993	97.82	0.1792	0.1786	0.1961	18.63

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	13.574
f_angle_d	1.334
f_chiral_restr	0.078
f_bond_d	0.009
f_plane_restr	0.007

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1328
Nucleic Acid Atoms
Solvent Atoms	202
Heterogen Atoms	60

Software

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

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.