3JC7 | pdb_00003jc7

Structure of the eukaryotic replicative CMG helicase and pumpjack motion

ELECTRON MICROSCOPY

---

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	2Q9Q

Sample
Saccharomyces cerevisiae CMG complex

Specimen Preparation
Sample Aggregation State	PARTICLE
Vitrification Instrument	FEI VITROBOT MARK IV
Cryogen Name	ETHANE
Sample Vitrification Details	Blot for 3 seconds before plunging into liquid ethane (FEI VITROBOT MARK IV).

3D Reconstruction
Reconstruction Method	SINGLE PARTICLE
Number of Particles	86822
Reported Resolution (Å)	4.8
Resolution Method	FSC 0.143 CUT-OFF
Other Details	(Single particle details: All steps, including automatic particle picking, 2D classification, 3D classification, and 3D refinement were performed in Relion 1.4.) (Single particle--Applied symmetry: C1)
Refinement Type
Symmetry Type	POINT
Point Symmetry	C1

Map-Model Fitting and Refinement
Id	1 (2Q9Q)
Refinement Space	REAL
Refinement Protocol	RIGID BODY FIT
Refinement Target
Overall B Value
Fitting Procedure
Details	REFINEMENT PROTOCOL--rigid body

Data Acquisition
Detector Type	GATAN K2 SUMMIT (4k x 4k)
Electron Dose (electrons/Å**2)	50

Imaging Experiment	1
Date of Experiment	2015-08-01
Temperature (Kelvin)
Microscope Model	FEI TITAN KRIOS
Minimum Defocus (nm)	1500
Maximum Defocus (nm)	3500
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	29000
Calibrated Magnification	49505
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	300
Imaging Details

EM Software
Task	Software Package	Version
MODEL FITTING	UCSF Chimera
RECONSTRUCTION	RELION	1.4

Image Processing
CTF Correction Type	CTF Correction Details	Number of Particles Selected	Particle Selection Details
	CTFFIND4