1S3Y

Structure Determination of Tetrahydroquinazoline Antifolates in Complex with Human and Pneumocystis carinii Dihydrofolate Reductase: Correlations of Enzyme Selectivity and Stereochemistry


X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
IDMethodpHTemperatureDetails
1thermal gradient629850 mM MES, 100 mM KCl, pH 6.0, thermal gradient, temperature 298K
Crystal Properties
Matthews coefficientSolvent content
2.0740.52

Crystal Data

Unit Cell
Length ( Å )Angle ( ˚ )
a = 37.359α = 90
b = 43.286β = 94.65
c = 61.397γ = 90
Symmetry
Space GroupP 1 21 1

Diffraction

Diffraction Experiment
ID #Crystal IDScattering TypeData Collection TemperatureDetectorDetector TypeDetailsCollection DateMonochromatorProtocol
11x-ray298IMAGE PLATERIGAKU RAXIS IVmirrors1998-01-29MSINGLE WAVELENGTH
Radiation Source
ID #SourceTypeWavelength ListSynchrotron SiteBeamline
1ROTATING ANODERIGAKU RU2001.5418,1.5621,1.7321

Data Collection

Overall
ID #Resolution (High)Resolution (Low)Percent Possible (Observed)Net I Over Average Sigma (I)RedundancyNumber Reflections (All)Number Reflections (Observed)Observed Criterion Sigma (F)Observed Criterion Sigma (I)B (Isotropic) From Wilson Plot
12.255073.994646996
Highest Resolution Shell
ID #Resolution (High)Resolution (Low)Percent Possible (All)Percent Possible (Observed)R Merge I (Observed)Mean I Over Sigma (Observed)RedundancyNumber Unique Reflections (All)
2.252.3376.70.177

Refinement

Statistics
Diffraction IDStructure Solution MethodCross Validation methodResolution (High)Resolution (Low)Number Reflections (All)Number Reflections (Observed)Number Reflections (R-Free)Percent Reflections (Observed)R-Factor (All)R-Factor (Observed)R-WorkR-FreeR-Free Selection DetailsMean Isotropic B
X-RAY DIFFRACTIONFOURIER SYNTHESISTHROUGHOUT2.2550946469967640.2890.2330.2330.289random
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
KeyRefinement Restraint Deviation
c_improper_angle_d2.81
c_dihedral_angle_d1.68
c_angle_deg1.22
c_bond_d0.008
Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen AtomsNumber
Protein Atoms1685
Nucleic Acid Atoms
Solvent Atoms23
Heterogen Atoms70

Software

Software
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
CNSphasing