ELECTRON MICROSCOPY

Sample

Cobalamin-dependent methionine synthase holoprotein

Specimen Preperation
Sample Aggregation State 2D ARRAY
Vitrification Instrument FEI VITROBOT MARK IV
Cryogen Name ETHANE-PROPANE
Sample Vitrification Details ?
3D Reconstruction
Reconstruction Method SINGLE PARTICLE
Number of Particles 257706
Reported Resolution (Å) 3.6
Resolution Method FSC 0.143 CUT-OFF
Other Details ?
Refinement Type
Symmetry Type POINT
Map-Model Fitting and Refinement
ID 1
Refinement Space REAL
Refinement Protocol RIGID BODY FIT
Refinement Target ?
Overall B Value ?
Fitting Procedure ?
Details Initial model used was the 3 N-terminal domains of AlphaFold database model A0A1Q9SZ17. Each domain was fit individually by rigid-body fitting in Chimera. The cobalamin ligand was initially fit by alignment of the 1BMT crystal structure to the appropriate binding region.
Data Acquisition
Detector Type GATAN K3 (6k x 4k)
Electron Dose (electrons/Å2) 65
Imaging Experiment
Date of Experiment ?
Temprature (Kelvin)
Microscope Model FEI TITAN KRIOS
Minimum Defocus (nm) 800
Maximum Defocus (nm) 2500
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 81000
Calibrated Magnification ?
Source FIELD EMISSION GUN
Acceleration Voltage (kV) 300
Imaging Details ?
Imaging Experiment
Task Software Package Version
PARTICLE SELECTION cryoSPARC 3.2
IMAGE ACQUISITION Leginon ?
CTF CORRECTION cryoSPARC 3.2
MODEL FITTING UCSF Chimera 1.15
INITIAL EULER ASSIGNMENT cryoSPARC 3.2
FINAL EULER ASSIGNMENT cryoSPARC 3.2
CLASSIFICATION cryoSPARC 3.2
RECONSTRUCTION cryoSPARC 3.2
MODEL REFINEMENT ISOLDE 1.3
MODEL REFINEMENT PHENIX 1.20.1-4487
Image Processing
CTF Correction Type CTF Correction Details Number of Particles Selected Particle Selection Details
PHASE FLIPPING AND AMPLITUDE CORRECTION cryoSPARC patch CTF