Isoreticular co-crystal of Replication Initiator Protein REPE54 and asymmetrical expanded duplex (31mer) containing the cognate REPE54 sequence, and additional T-A rich sequence with 5' terminal phosphates. Two copies of Even-skipped homeodomain loaded post-crystallization
X-RAY DIFFRACTION
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | VAPOR DIFFUSION, SITTING DROP | 6.5 | 298 | 30mM Magnesium Acetate, 1.2M Lithium sulfate, 50mM MES pH 6.5. The crystal was crosslinked with 33mg/mL EDC overnight, and then looped into a solution of 15mM potassium chloride, 4mM calcium chloride, 10% glycerol, and 10mM Tris hydrochloride for 1 hour. The drop was then supplemented with 30 micromolar Even-skipped homeodomain |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 4.52 | 72.81 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 73.365 | α = 90 |
| b = 120.285 | β = 91.466 |
| c = 134.401 | γ = 90 |
| Symmetry | |
|---|---|
| Space Group | I 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 | PIXEL | DECTRIS EIGER X 9M | 2025-04-13 | M | SINGLE WAVELENGTH | ||||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | ALS BEAMLINE 8.2.1 | 1.0 | ALS | 8.2.1 |
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 | 3.02 | 46.31 | 98.3 | 0.198 | 0.234 | 0.124 | 0.966 | 3.8 | 3.5 | 22518 | 86.65 | ||||||||
| 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 | 3.02 | 3.19 | 98.5 | 1.428 | 1.675 | 0.868 | 0.622 | 0.9 | 3.6 | ||||||||||
Refinement
| Statistics | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diffraction ID | Structure Solution Method | Cross Validation method | Resolution (High) | Resolution (Low) | Cut-off Sigma (F) | 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 | FREE R-VALUE | 3.02 | 44.81 | 1.34 | 22418 | 2223 | 97.63 | 0.2836 | 0.2825 | 0.283 | 0.2942 | 0.2951 | 139.96 | |||||
| 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 | 24.5879 |
| f_angle_d | 0.6035 |
| f_chiral_restr | 0.0415 |
| f_plane_restr | 0.0049 |
| f_bond_d | 0.0036 |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 2203 |
| Nucleic Acid Atoms | 1271 |
| Solvent Atoms | |
| Heterogen Atoms | 2 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| PHENIX | refinement |
| XDS | data reduction |
| XSCALE | data scaling |
| PHASER | phasing |
| Coot | model building |
