6XG4

X-ray structure of Escherichia coli dihydrofolate reductase L28R mutant in complex with trimethoprim

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	5.6	293	0.1 M sodium citrate tribasic dihydrate (pH 5.6), 0.15 M ammonium acetate and 17.5% or 20% PEG 4000; 10 mM NADPH, 2 mM TMP was incubated with the L28R variant of DHFR overnight at 293 K

Crystal Properties
Matthews coefficient	Solvent content
3.03	59.39

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 61.548	α = 90
b = 61.548	β = 90
c = 104.661	γ = 120

Symmetry
Space Group	P 32 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 PILATUS 6M		2018-07-12	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	APS BEAMLINE 19-ID	0.97919	APS	19-ID

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (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	2.1	50	99.9	0.076	0.025	1	37.5	9.3		13880		-3

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	Rrim I (All)	Rpim I (All)	CC (Half)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	2.1	2.12	100		8.94	3.012	0.672	0.7	8.8

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	WT DHFR solved in the same space group	2.1	37.37	9837		70.95	0.2493	0.2493	0.2779	FULL CROSS VALIDATION	35.198

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]
-0.11	-0.05		-0.11		0.35

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	33.498
r_dihedral_angle_3_deg	18.538
r_dihedral_angle_4_deg	13.371
r_dihedral_angle_1_deg	7.56
r_angle_refined_deg	1.417
r_angle_other_deg	1.112
r_chiral_restr	0.054
r_bond_refined_d	0.006
r_gen_planes_refined	0.006
r_bond_other_d	0.001

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	33.498
r_dihedral_angle_3_deg	18.538
r_dihedral_angle_4_deg	13.371
r_dihedral_angle_1_deg	7.56
r_angle_refined_deg	1.417
r_angle_other_deg	1.112
r_chiral_restr	0.054
r_bond_refined_d	0.006
r_gen_planes_refined	0.006
r_bond_other_d	0.001
r_gen_planes_other	0.001

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1271
Nucleic Acid Atoms
Solvent Atoms	131
Heterogen Atoms	76

Software

Software
Software Name	Purpose
REFMAC	refinement
PDB_EXTRACT	data extraction
HKL-3000	data reduction
HKL-3000	data scaling
MOLREP	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.