6I5T
Cryo-EM informed directed evolution of Nitrilase 4 leads to a change in quaternary structure.
ELECTRON MICROSCOPY
| Sample |
|---|
| Active helical nitrilase complex |
| Specimen Preparation | |
|---|---|
| Sample Aggregation State | FILAMENT |
| Vitrification Instrument | FEI VITROBOT MARK I |
| Cryogen Name | ETHANE |
| Sample Vitrification Details | The sample (2.5 ul) was applied to the grid and incubated for 30 seconds at 50% humidity before blotting and plunging. |
| 3D Reconstruction | |
|---|---|
| Reconstruction Method | HELICAL |
| Number of Particles | 46493 |
| Reported Resolution (Å) | 3.9 |
| Resolution Method | FSC 0.143 CUT-OFF |
| Other Details | |
| Refinement Type | |
| Symmetry Type | HELICAL |
| Axial Symmetry | C1 |
| Axial Rise | 17.31 |
| Angular Rotation | 72.77 |
| Map-Model Fitting and Refinement | |||||
|---|---|---|---|---|---|
| Id | 1 | ||||
| Refinement Space | REAL | ||||
| Refinement Protocol | AB INITIO MODEL | ||||
| Refinement Target | Cross-correlation coefficient | ||||
| Overall B Value | |||||
| Fitting Procedure | |||||
| Details | Ab initio fitting was performed using Buccaneer, cleaned up with Coot and Phenix Real-Space Refine. | ||||
| Data Acquisition | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Detector Type | GATAN K2 SUMMIT (4k x 4k) | ||||||||
| Electron Dose (electrons/Å**2) | 45.5 | ||||||||
| Imaging Experiment | 1 |
|---|---|
| Date of Experiment | |
| Temperature (Kelvin) | |
| Microscope Model | FEI TITAN KRIOS |
| Minimum Defocus (nm) | 750 |
| Maximum Defocus (nm) | 2000 |
| Minimum Tilt Angle (degrees) | |
| Maximum Tilt Angle (degrees) | |
| Nominal CS | 2.7 |
| Imaging Mode | BRIGHT FIELD |
| Specimen Holder Model | FEI TITAN KRIOS AUTOGRID HOLDER |
| Nominal Magnification | |
| Calibrated Magnification | |
| Source | FIELD EMISSION GUN |
| Acceleration Voltage (kV) | 300 |
| Imaging Details |
| EM Software | ||
|---|---|---|
| Task | Software Package | Version |
| IMAGE ACQUISITION | EPU | 1.9.1 |
| CTF CORRECTION | Gctf | 1.06 |
| MODEL REFINEMENT | PHENIX | 1.14 |
| INITIAL EULER ASSIGNMENT | RELION | 2.0 |
| FINAL EULER ASSIGNMENT | RELION | 2.0 |
| CLASSIFICATION | RELION | 2.0 |
| RECONSTRUCTION | RELION | 2.0 |
| Image Processing | ||||
|---|---|---|---|---|
| CTF Correction Type | CTF Correction Details | Number of Particles Selected | Particle Selection Details | |
| PHASE FLIPPING AND AMPLITUDE CORRECTION | 133106 | 3D class with a 72.8 degree average helical twist | ||
