EMD-2520 Experiments and Validation

Injectisome in the tomogram of Salmonella mini-cell

Subtomogram averaging
Overview of EMD-2520
Sample name: Injectisome from Salmonella typhimurium mini-cell in situ
Organism: Salmonella enterica subsp. enterica serovar Typhimurium
Related EM entry by publication: EMD-2521

Map parameters

Minimum density: -2.03
Maximum density: 5.21
Average density: 0.02
Standard deviation: 0.9
Recommended contour level: 0.24 (author)

Sample information

Sample name: Injectisome from Salmonella typhimurium mini-cell in situ
Cellular component: type III secretion system

Validation information

Experimental information

 

Image processing

Applied symmetry: C24
Software: EMAN
Number of subtomograms averaged: 75
Reconstruction protocol: subtomogram averaging

Imaging

Session
Microscope model: FEI TITAN KRIOS
Electron source: FIELD EMISSION GUN
Electron dose (e/A**2): 200.0
Nominal CS (mm): 2.7
Nominal magnification: 29000.0
Defocus max (nm): 7,000
Defocus min (nm): 4,000
Tilt max (degrees): 70
Tilt min (degrees): -70
Holder model: FEI TITAN KRIOS AUTOGRID HOLDER

Specimen

Preparation
Specimen state: cell
Buffer: M9 medium (17.1g Na2HPO4-12H2O, 3g KH2PO4, 0.5g NaCl, 1g NH4Cl, 0.2%glycerol, 1% typtone, 1mM MgSO4 per litre)
Specimen support: Quantifoil molybdenum 200 mesh R0.6/1.0 grid with thin carbon support
Vitrification
Apparatus: FEI VITROBOT MARK II
Cryogen: ETHANE
Humidity: 100