4XEJ
IRES bound to bacterial Ribosome
X-RAY DIFFRACTION
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | VAPOR DIFFUSION, HANGING DROP | 7 | 295.5 | Initial crystallization screening was performed around conditions previously reported (31, 48) by dispensing 0.2 + 0.2 mL sitting drops with a Phoenix robotic liquid handling system (Art Robbins) on 96-well plates. Once optimal crystallization conditions were determined, crystals were grown by the sitting-drop vapor-diffusion method using drops dispensed by the Phoenix with 1- to 2-mL ribosome complexes mixed with 1-2 mL of reservoir solution [100 mM Tris-OAc, pH 7.0, 200 mM potassium thiocyanate (KSCN), 3.6-5% PEG 20,000, 6-14% 2-methyl-2,4-pentanediol (MPD)] at 22.5C. Crystals emerged after 5-7 d and matured between 2-3 wk. Crystals were then subjected to cryoprotection by gradually replacing the mother liquor with cryoprotection buffer I (100 mM Tris-OAc, pH 7.0, 200 mM KSCN, 5% PEG 20,000, 25% MPD, 14% PEG 200, and 10 mM Mg(OAc)2). The crystals then were flash-frozen by plunging into liquid nitrogen. |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 3.34 | 63.19 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 209.05 | α = 90 |
| b = 447.22 | β = 90 |
| c = 608.96 | γ = 90 |
| Symmetry | |
|---|---|
| Space Group | P 21 21 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 | CCD | MARMOSAIC 300 mm CCD | 2010-10-20 | M | SINGLE WAVELENGTH | ||||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | APS BEAMLINE 23-ID-B | 1.033 | APS | 23-ID-B |
Data Collection
| Overall | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (Observed) | Rrim I (All) | CC (Half) | 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 | 3.8 | 60 | 99.9 | 0.2 | 0.995 | 8.28 | 4.8 | 555726 | |||||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | Rrim I (All) | CC (Half) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | ||||||||||
| 1 | 3.8 | 4 | 99.8 | 1.6 | 0.998 | 1.2 | 3.4 | ||||||||||||
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-Work | R-Free | Mean Isotropic B | ||||||||
| X-RAY DIFFRACTION | MOLECULAR REPLACEMENT | FREE R-VALUE | PDB entry 4V83 | 3.8 | 60 | 555726 | 2000 | 99.9 | 0.246 | 0.284 | |||||||||
| 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] | |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 92320 |
| Nucleic Acid Atoms | 194969 |
| Solvent Atoms | |
| Heterogen Atoms | 4 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| PHENIX | refinement |
| XDS | data reduction |
| XSCALE | data scaling |
| PHENIX | phasing |
