A re-determination of the structure of the triple mutant (K53,56,120M) of phospholipase A2 at 1.6A resolution using sulphur-SAS at 1.54A wavelength
X-RAY DIFFRACTION
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | vapor diffusion method | 7.2 | 293 | 50 mM Tris Buffer, 70% MPD reservoir,17-20Mg/ml prot,5 mM CaCl2 and 60% MPD in the droplet, pH 7.2, vapor diffusion method, temperature 293.0K |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 2.25 | 45.32 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 46.05 | α = 90 |
| b = 46.05 | β = 90 |
| c = 101.58 | γ = 120 |
| Symmetry | |
|---|---|
| Space Group | P 31 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 | CCD | MARRESEARCH | M | SINGLE WAVELENGTH | |||||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | NSLS BEAMLINE X9A | NSLS | X9A | |
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 | 1.6 | 19.96 | 0.059 | 50.1 | 12.1 | 17048 | |||||||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | R Merge I (Observed) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | |||||||||||
| 1.6 | 1.66 | 0.284 | 3188 | ||||||||||||||||
Refinement
| Statistics | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diffraction ID | Structure Solution Method | Cross Validation method | Resolution (High) | Resolution (Low) | Number Reflections (All) | 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 | SULPHUR-SAS | THROUGHOUT | 1.6 | 19.96 | 17048 | 16184 | 860 | 99.66 | 0.17893 | 0.17703 | 0.18 | 0.21658 | 0.21 | RANDOM | 24.462 | ||||
| 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] | |
| -0.02 | -0.01 | -0.02 | 0.03 | |||
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| r_dihedral_angle_1_deg | 5.62 |
| r_scangle_it | 4.071 |
| r_scbond_it | 2.569 |
| r_mcangle_it | 1.671 |
| r_angle_refined_deg | 1.536 |
| r_mcbond_it | 0.88 |
| r_symmetry_vdw_refined | 0.227 |
| r_nbd_refined | 0.203 |
| r_xyhbond_nbd_refined | 0.173 |
| r_symmetry_hbond_refined | 0.123 |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 954 |
| Nucleic Acid Atoms | |
| Solvent Atoms | 189 |
| Heterogen Atoms | 2 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| DENZO | data reduction |
| REFMAC | refinement |
| SCALEPACK | data scaling |














