3JA6

Cryo-electron Tomography and All-atom Molecular Dynamics Simulations Reveal a Novel Kinase Conformational Switch in Bacterial Chemotaxis Signaling

ELECTRON MICROSCOPY

Sample
CheA2-trimer core complex
Sample Components
Chemotaxis protein CheA
Chemotaxis protein CheW
Methyl-accepting chemotaxis protein II

Specimen Preparation
Sample Aggregation State	PARTICLE
Vitrification Instrument	HOMEMADE PLUNGER
Cryogen Name	ETHANE
Sample Vitrification Details	Single-sided blotting (to avoid disruption of the monolayer) before plunging into liquid ethane

3D Reconstruction
Reconstruction Method	TOMOGRAPHY
Number of Particles	4000
Reported Resolution (Å)	12.7
Resolution Method	FSC 0.143 CUT-OFF
Other Details	Gold-standard refinement
Refinement Type	HALF-MAPS REFINED INDEPENDENTLY
Symmetry Type	2D CRYSTAL
Point Symmetry	C2

Map-Model Fitting and Refinement
Id	1 (1QU7)
Refinement Space	REAL
Refinement Protocol	FLEXIBLE FIT
Refinement Target
Overall B Value
Fitting Procedure
Details	REFINEMENT PROTOCOL--FLEXIBLE

Data Acquisition
Detector Type	GATAN ULTRASCAN 4000 (4k x 4k)
Electron Dose (electrons/Å**2)	60

Imaging Experiment	1
Date of Experiment	2009-01-07
Temperature (Kelvin)
Microscope Model	FEI POLARA 300
Minimum Defocus (nm)	4000
Maximum Defocus (nm)	8000
Minimum Tilt Angle (degrees)	-70
Maximum Tilt Angle (degrees)	70
Nominal CS	2
Imaging Mode	BRIGHT FIELD
Specimen Holder Model	OTHER
Nominal Magnification	39000
Calibrated Magnification	49834
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	200
Imaging Details

Image Processing
CTF Correction Type	CTF Correction Details	Number of Particles Selected	Particle Selection Details
	TomoCTF (strip-based periodogram)

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.