3M4A
Crystal structure of a bacterial topoisomerase IB in complex with DNA reveals a secondary DNA binding site
X-RAY DIFFRACTION
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | VAPOR DIFFUSION, HANGING DROP | 4.5 | 283 | 30% PEG 400 (w/v), 0.1 M sodium acetate (pH 4.5), 0.2 M calcium chloride. 1:1 molar ratio of protein and DNA, VAPOR DIFFUSION, HANGING DROP, temperature 283K |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 2.65 | 53.57 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 119.67 | α = 90 |
| b = 53.44 | β = 96.33 |
| c = 77.36 | 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 | 100 | IMAGE PLATE | MAR scanner 345 mm plate | Franks mirrors | 2006-01-01 | M | SINGLE WAVELENGTH | |||||
| 2 | 1 | x-ray | 100 | CCD | MAR CCD 165 mm | 2006-03-01 | M | SINGLE WAVELENGTH | ||||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | ROTATING ANODE | RIGAKU RU200 | 1.5418 | ||
| 2 | SYNCHROTRON | 1.00 | |||
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 | |||||||
| 1,2 | 1.65 | 76 | 96.2 | 0.053 | 0.048 | 24.1 | 4.7 | 58613 | 56385 | ||||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | R Merge I (Observed) | R-Sym I (Observed) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | ||||||||||
| 1.65 | 1.69 | 89.5 | 0.325 | 0.276 | 4.1 | 3.4 | |||||||||||||
Refinement
| Statistics | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diffraction ID | Structure Solution Method | Cross Validation method | Starting model | Resolution (High) | Resolution (Low) | Number Reflections (All) | Number Reflections (Observed) | Number Reflections (R-Free) | Percent Reflections (Observed) | R-Factor (All) | R-Factor (Observed) | R-Work | R-Free | R-Free Selection Details | Mean Isotropic B | ||||
| X-RAY DIFFRACTION | MOLECULAR REPLACEMENT | THROUGHOUT | PDB entry 2F4Q | 1.65 | 19.824 | 58613 | 53565 | 2820 | 96.16 | 0.19487 | 0.19487 | 0.19344 | 0.22169 | RANDOM | 13.658 | ||||
| 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] | |
| 0.3 | 0.01 | -0.72 | 0.43 | |||
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| r_dihedral_angle_2_deg | 32.368 |
| r_dihedral_angle_3_deg | 12.094 |
| r_dihedral_angle_4_deg | 11.133 |
| r_dihedral_angle_1_deg | 4.818 |
| r_scangle_it | 2.479 |
| r_scbond_it | 1.743 |
| r_angle_refined_deg | 1.29 |
| r_mcangle_it | 1.017 |
| r_angle_other_deg | 0.947 |
| r_mcbond_it | 0.936 |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 2420 |
| Nucleic Acid Atoms | 486 |
| Solvent Atoms | 281 |
| Heterogen Atoms | 9 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| MAR345dtb | data collection |
| PHASER | phasing |
| REFMAC | refinement |
| XDS | data reduction |
| SCALA | data scaling |
