Human Dihydrofolate Reductase Complexed With NADPH and 2,4-Diamino-5-(1-o-carboranylmethyl)-6-methylpyrimidine, A novel boron containing, nonclassical Antifolate
X-RAY DIFFRACTION
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | VAPOR DIFFUSION, HANGING DROP | 8 | 277 | THE TERNARY COMPLEX OF DHFR WITH NADPH AND 34B WAS FORMED BY MIXING HUMAN DHFR (20 MG/ML IN 25 MM KPO4 (PH 7.0), 0.1 MM EDTA, AND 3 MM NAN3) WITH 60 MM NADPH, FOLLOWED 15 MINUTES LATER BY 60 MM OF INHIBITOR IN DMSO (FINAL CONCENTRATIONS OF 2 MM NADPH AND 2 MM INHIBITOR). THIS COMPLEX SOLUTION WAS MIXED WITH AN EQUAL VOLUME OF PRECIPITANT CONTAINING 24-33% PEG 4000, 0.2 M LI2SO4, 0.1 M TRIS CL (PH 7.9-8.4), 5% GLYCEROL, AND EQUILIBRATED WITH THE PRECIPITANT BY HANGING DROP VAPOR DIFFUSION AT 277 K. THE CRYSTAL GREW IN ABOUT 3 WEEKS. THE CRYSTAL WAS FLASH-COOLED DIRECTLY IN LIQUID NITROGEN AFTER HARVESTING INTO MOTHER LIQUOR CONTAINING 10% GLYCEROL. |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 2.3 | 46.3 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 87.671 | α = 90 |
| b = 93.864 | β = 90 |
| c = 95.782 | γ = 90 |
| Symmetry | |
|---|---|
| Space Group | C 2 2 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 | IMAGE PLATE | MARRESEARCH | MIRROR | 1999-03-02 | M | SINGLE WAVELENGTH | |||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | SSRL BEAMLINE BL9-1 | SSRL | BL9-1 | |
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 | 1.4 | 35 | 84 | 0.05 | 11.2 | 3 | 65300 | 16.1 | |||||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | R Merge I (Observed) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | |||||||||||
| 1 | 1.4 | 1.44 | 43.1 | 0.46 | 1.5 | 1.3 | |||||||||||||
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 (Depositor) | R-Work (DCC) | R-Free (Depositor) | R-Free (DCC) | R-Free Selection Details | Mean Isotropic B | ||||
| X-RAY DIFFRACTION | MOLECULAR REPLACEMENT | THROUGHOUT | UNPUBLISHED HUMAN DHFR STRUCTURE | 1.4 | 20 | 61984 | 3260 | 83.9 | 0.157 | 0.155 | 0.22 | 0.198 | 0.26 | RANDOM | 19.68 | ||||
| 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] | |
| -0.16 | 0.18 | -0.02 | ||||
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| r_dihedral_angle_2_deg | 39.123 |
| r_dihedral_angle_3_deg | 12.65 |
| r_dihedral_angle_4_deg | 12.302 |
| r_dihedral_angle_1_deg | 6.022 |
| r_angle_refined_deg | 1.553 |
| r_angle_other_deg | 1.213 |
| r_nbd_refined | 0.203 |
| r_symmetry_vdw_other | 0.202 |
| r_nbd_other | 0.192 |
| r_nbtor_refined | 0.177 |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 2962 |
| Nucleic Acid Atoms | |
| Solvent Atoms | 556 |
| Heterogen Atoms | 146 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| REFMAC | refinement |
| MOSFLM | data reduction |
| SCALA | data scaling |
| AMoRE | phasing |














