1E26

Design, Synthesis and X-ray Crystal Structure of a Potent Dual Inhibitor of Thymidylate Synthase and Dihydrofolate Reductase as an Antitumor Agent.

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	MICROBATCH	6		PROTEIN SOLUTION: WASHED AND CONCENTRATED 4 TUBES PCDHFR USING A CENTRICON 10 50 MM MES, 100MM KCL, B-NADPH, PH 6.0, A280/340 RATIO OF 24. WASHED WITH 50MM MES, 100MM KCL, PH 6.0, WASHED WITH 50MM MES, 100MM KCL, PH 6.0 TO A CONCENTRATION OF 6.5 MG/ML. RESERVOIR SOLUTION: 50% PEG2000MME, 50MM MES, 100MM, PH 6.0 SET UP MICROBATCH POLYTHERMAL GRADIENT EXPERIMENTS IN MICROPETS. DROPS WERE COMPOSED OF: 2.5 MICROLITERS PROTEIN SOLUTION 2.0 MICROLITERS PROTEIN SOLUTION 0.5 MICROLITERS 50MM MES, 100MM KCL, PH 6.0. MICROPETS WERE LEFT TO EQUILIBRATE ON THE POLYTHERMAL GRADIENT.

Crystal Properties
Matthews coefficient	Solvent content
1.97	48

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 37.332	α = 90
b = 43.231	β = 94.59
c = 61.241	γ = 90

Symmetry
Space Group	P 1 21 1

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	293	IMAGE PLATE	RIGAKU RAXIS IIC		1999-01-15	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	ROTATING ANODE	RIGAKU RU200HB

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Merge I (Observed)	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	100	99.4	0.054		2.6		11919		2

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	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	2CD2	2	100	13297			0.2185	0.2185	0.2968

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
c_angle_deg	1.5
c_bond_d	0.008
c_bond_d_na
c_bond_d_prot
c_angle_d
c_angle_d_na
c_angle_d_prot
c_angle_deg_na
c_angle_deg_prot
c_dihedral_angle_d
c_dihedral_angle_d_na
c_dihedral_angle_d_prot
c_improper_angle_d
c_improper_angle_d_na
c_improper_angle_d_prot
c_mcbond_it
c_mcangle_it
c_scbond_it
c_scangle_it

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1678
Nucleic Acid Atoms
Solvent Atoms	101
Heterogen Atoms	79

Software

Software
Software Name	Purpose
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling