Crystal structure of TS-DHFR from Cryptosporidium hominis in complex with NADPH, methotrexate, FdUMP and 4-((2-amino-6-methyl-4-oxo-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-5-yl)thio)-2-chlorophenyl)-L-glutamic acid
X-RAY DIFFRACTION
Starting Model(s)
| Initial Refinement Model(s) | |||
|---|---|---|---|
| Type | Source | Accession Code | Details |
| experimental model | PDB | 1QZF | PDB ENTRY 1QZF |
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | VAPOR DIFFUSION, HANGING DROP | 8 | 298 | 14% (w/v) PEG 6000, 60 mM ammonium sulfate, 200 mM lithium sulfate and 100 mM Tris pH 8.0. ChTS-DHFR enzyme (~ 7 mg/ml) with 1 mM NADPH, 1 mM MTX, 1 mM FdUMP and 0.5 mM inhibitor., VAPOR DIFFUSION, HANGING DROP, temperature 298K |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 4.48 | 72.56 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 214.162 | α = 90 |
| b = 115.665 | β = 94.36 |
| c = 218.767 | γ = 90 |
| Symmetry | |
|---|---|
| Space Group | C 1 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 | 77 | PIXEL | DECTRIS PILATUS 6M | monochromator | 2013-04-16 | M | SINGLE WAVELENGTH | |||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | NSLS BEAMLINE X25 | 1.10 | NSLS | X25 |
Data Collection
| Overall | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (Observed) | R Merge I (Observed) | R Sym 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 | 3.08 | 48.12 | 71.6 | 0.207 | 0.207 | 4.1 | 3 | 70173 | 1.5 | 70.12 | |||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | ||||||||||||
| 1 | 3.1 | 3.15 | 11.3 | 1.3 | |||||||||||||||
Refinement
| Statistics | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diffraction ID | Structure Solution Method | Starting model | Resolution (High) | Resolution (Low) | Cut-off Sigma (F) | Number Reflections (All) | 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) | Mean Isotropic B | ||||
| X-RAY DIFFRACTION | MOLECULAR REPLACEMENT | PDB ENTRY 1QZF | 3.084 | 48.12 | 1.34 | 70048 | 70048 | 1959 | 71.2 | 0.233 | 0.232 | 0.23 | 0.2663 | 0.27 | 82.3969 | ||||
| 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 | 12.125 |
| f_angle_d | 0.543 |
| f_chiral_restr | 0.039 |
| f_bond_d | 0.002 |
| f_plane_restr | 0.002 |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 20570 |
| Nucleic Acid Atoms | |
| Solvent Atoms | |
| Heterogen Atoms | 670 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| DENZO | data reduction |
| SCALEPACK | data scaling |
| PHENIX | refinement |
| PDB_EXTRACT | data extraction |
| CBASS | data collection |
| HKL-2000 | data reduction |
| HKL-2000 | data scaling |
| PHASER | phasing |














