Room Temperature Structure of SARS-CoV-2 Nsp10/Nsp16 Methyltransferase in a Complex with 2'-O-methylated m7GpppA Cap-1 and SAH Determined by Fixed-Target Serial Crystallography
X-RAY DIFFRACTION
Serial Crystallography (SX)
Starting Model(s)
| Initial Refinement Model(s) | |||
|---|---|---|---|
| Type | Source | Accession Code | Details |
| experimental model | PDB | 6WQ3 | |
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | BATCH MODE | 6.5 | 295 | Protein: 4.0 mg/ml (NSP10/NSP16 1:1), 0.15 M NaCl, 0.01 M Tris-HCl, 2 mM SAM, 1 mM TCEP, 5% Glycerol, pH 7.5. Precipitation buffer: 0.1 M MES pH 6.5, 0.9 M NaF. Batch crystallization: 100 ul of protein mixed with 100 ul of precipitation buffer in 500 ul polypropylene tube. Crystals were soaked with m7GpppA (0.5 mM) for 10 minutes before data collection. |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 4.46 | 72.5 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 170.859 | α = 90 |
| b = 170.859 | β = 90 |
| c = 52.797 | 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 | 295 | PIXEL | DECTRIS PILATUS3 X 6M | Sagittally focusing mono and vertically focusing mirror | 2020-06-12 | M | SINGLE WAVELENGTH | |||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | APS BEAMLINE 19-ID | 0.97918 | APS | 19-ID |
Serial Crystallography
| Sample delivery method | ||
|---|---|---|
| Diffraction ID | Description | Sample Delivery Method |
| 1 | Nylon Mesh | fixed target |
| Fixed Target | ||||||
|---|---|---|---|---|---|---|
| Diffraction ID | Description | Sample Holding | Support Base | Motion control | Details | Sample Solvent |
| 1 | SBC Mesh Holder | mesh | xyz stage | SmarAct Motors viaPMAC | start/stop raster over area | 50 mM MES pH 6.5, 0.45 M NaF, 75 mM NaCl, 5 mM Tris-HCl, 1 mM SAM, 0.5 mM TCEP, 2.5% Glycerol, 0.5 mM m7GpppA |
| Data Reduction | ||||
|---|---|---|---|---|
| Diffraction ID | Frames Indexed | Crystal Hits | Frames Indexed | Latices Merged |
| 1 | 7725 | 7725 | 7725 | |
Data Collection
| Overall | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (Observed) | 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 | 2.25 | 49.73 | 100 | 0.93 | 2.45 | 42.94 | 42145 | 21.4 | |||||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | CC (Half) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | |||||||||||
| 1 | 2.25 | 2.29 | 99.8 | 0.473 | 0.66 | 9.28 | |||||||||||||
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 | 6WQ3 | 2.25 | 49.73 | 40062 | 2065 | 99.93 | 0.2243 | 0.2231 | 0.2276 | 0.2485 | 0.2519 | RANDOM | 37.147 | ||||
| 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] | |
| -0.01 | -0.01 | 0.02 | ||||
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| r_dihedral_angle_2_deg | 28.016 |
| r_dihedral_angle_3_deg | 10.373 |
| r_dihedral_angle_4_deg | 9.598 |
| r_dihedral_angle_1_deg | 3.003 |
| r_angle_refined_deg | 1.353 |
| r_angle_other_deg | 0.356 |
| r_gen_planes_refined | 0.053 |
| r_chiral_restr | 0.052 |
| r_gen_planes_other | 0.05 |
| r_bond_refined_d | 0.005 |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 3193 |
| Nucleic Acid Atoms | |
| Solvent Atoms | 160 |
| Heterogen Atoms | 114 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| REFMAC | refinement |
| PDB_EXTRACT | data extraction |
| MOLREP | phasing |
| DIALS | data scaling |
| DIALS | data reduction |














