Crystal Structure of Tricyclo-DNA: An Unusual Compensatory Change of Two Adjacent Backbone Torsion Angles
X-RAY DIFFRACTION
Starting Model(s)
| Initial Refinement Model(s) | |||
|---|---|---|---|
| Type | Source | Accession Code | Details |
| experimental model | PDB | 1EHV | PDB ENTRY 1EHV |
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | VAPOR DIFFUSION, HANGING DROP | 7 | 291 | 0.75 mM of oligonucleotide, 20 mM sodium cacodylate, 6 mM NaCl, 40 mM KCl and 5% MPD against 0.7 mL of 35% MPD, pH 7.0, VAPOR DIFFUSION, HANGING DROP, temperature 291K |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 2.71 | 54.58 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 26.587 | α = 90 |
| b = 26.587 | β = 90 |
| c = 98.238 | γ = 120 |
| Symmetry | |
|---|---|
| Space Group | P 32 |
Diffraction
| Diffraction Experiment | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Crystal ID | Scattering Type | Data Collection Temperature | Detector | Detector Type | Details | Collection Date | Monochromator | Protocol | |||||
| 1 | 1 | x-ray | 120 | CCD | ADSC QUANTUM 315 | Flat focusing mirror | 2007-05-02 | M | SINGLE WAVELENGTH | |||||
| 2 | 1 | |||||||||||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | NSLS BEAMLINE X29A | 1.0809 | NSLS | X29A |
| 2 | SYNCHROTRON | APS BEAMLINE 5ID-B | APS | 5ID-B | |
Data Collection
| Overall | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (Observed) | R Merge 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 | 1.75 | 32.74 | 88 | 0.049 | 23.2 | 3.6 | 7823 | 6884 | |||||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | ||||||||||||
| 1.75 | 1.796 | 60 | |||||||||||||||||
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-Factor (Observed) | R-Work (Depositor) | R-Work (DCC) | R-Free (Depositor) | R-Free (DCC) | R-Free Selection Details | Mean Isotropic B | ||||
| X-RAY DIFFRACTION | MOLECULAR REPLACEMENT | THROUGHOUT | PDB ENTRY 1EHV | 1.75 | 32.74 | 6551 | 332 | 88.01 | 0.17829 | 0.17602 | 0.19 | 0.22495 | 0.25 | RANDOM | 23.477 | ||||
| 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] | |
| 0.33 | 0.17 | 0.33 | -0.5 | |||
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| r_scangle_it | 2.576 |
| r_angle_other_deg | 1.849 |
| r_scbond_it | 1.839 |
| r_angle_refined_deg | 1.757 |
| r_nbtor_refined | 0.238 |
| r_symmetry_vdw_other | 0.233 |
| r_nbd_other | 0.197 |
| r_symmetry_vdw_refined | 0.178 |
| r_xyhbond_nbd_refined | 0.106 |
| r_symmetry_hbond_refined | 0.096 |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | |
| Nucleic Acid Atoms | 492 |
| Solvent Atoms | 93 |
| Heterogen Atoms | 15 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| REFMAC | refinement |
| ADSC | data collection |
| HKL-2000 | data reduction |
| HKL-2000 | data scaling |
| MOLREP | phasing |
| CNS | refinement |














