8QRE
Cholera holotoxin (wildtype)
X-RAY DIFFRACTION
Starting Model(s)
| Initial Refinement Model(s) | |||
|---|---|---|---|
| Type | Source | Accession Code | Details |
| experimental model | PDB | 1S5E | stripped of solvent and ligand molecules, used one copy of the holotoxin (1 A subunit, 5 B subunits) as the search model |
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | VAPOR DIFFUSION, SITTING DROP | 7.4 | 293.15 | Crystallization mix: 0.125 M Magnesium acetate 24% PEG 3350 300 mM galactose (in protein storage buffer) Protein storage buffer: 50 mM Tris pH 7.4 200 mM NaCl 1 mM EDTA 3 mM sodium azide |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 2.4 | 48.7 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 60.659 | α = 90 |
| b = 108.128 | β = 95.958 |
| c = 124.765 | γ = 90 |
| Symmetry | |
|---|---|
| Space Group | P 1 21 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 | PIXEL | DECTRIS EIGER2 X 9M | 2021-06-11 | M | SINGLE WAVELENGTH | ||||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | ESRF BEAMLINE ID30B | 0.9763 | ESRF | ID30B |
Data Collection
| Overall | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (Observed) | R Merge I (Observed) | Rrim I (All) | Rpim 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 | 2.3 | 124.091 | 98.6 | 0.256 | 0.308 | 0.169 | 0.97 | 4.3 | 3 | 70169 | 38.7 | ||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | R Merge I (Observed) | Rrim I (All) | Rpim I (All) | CC (Half) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | ||||||||
| 1 | 2.3 | 2.35 | 99.3 | 2.014 | 2.453 | 1.382 | 0.17 | 0.6 | |||||||||||
Refinement
| Statistics | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diffraction ID | Structure Solution Method | Cross Validation method | Resolution (High) | Resolution (Low) | Number Reflections (Observed) | Number Reflections (R-Free) | Percent Reflections (Observed) | R-Factor (All) | R-Work | R-Free | Mean Isotropic B | ||||||||
| X-RAY DIFFRACTION | MOLECULAR REPLACEMENT | FREE R-VALUE | 2.3 | 124.091 | 70169 | 3634 | 98.558 | 0.218 | 0.2159 | 0.2629 | 42.784 | ||||||||
| 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] | |
| -0.735 | 0.434 | -1.087 | 1.694 | |||
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| r_dihedral_angle_3_deg | 14.62 |
| r_dihedral_angle_6_deg | 14.512 |
| r_lrange_it | 8.932 |
| r_lrange_other | 8.931 |
| r_dihedral_angle_1_deg | 8.188 |
| r_scangle_it | 6.432 |
| r_scangle_other | 6.432 |
| r_mcangle_other | 5.064 |
| r_mcangle_it | 5.061 |
| r_scbond_it | 4.034 |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 11891 |
| Nucleic Acid Atoms | |
| Solvent Atoms | 354 |
| Heterogen Atoms | 239 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| REFMAC | refinement |
| autoPROC | data reduction |
| Aimless | data scaling |
| PHASER | phasing |
| MxCuBE | data collection |
| Coot | model building |
