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Automation in Single-Particle Electron Microscopy Jian Guan Hafenstein Lab

Automation in Single-Particle Electron Microscopy

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Automation in Single-Particle Electron Microscopy. Jian Guan Hafenstein Lab. The definition of Automation. “automation is a comprehensive and versatile strategy that can deliver biological information on an unprecedented scale beyond the scope available with classical manual approaches”. - PowerPoint PPT Presentation

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Page 1: Automation in Single-Particle Electron Microscopy

Automation in Single-Particle Electron MicroscopyJian GuanHafenstein Lab

Page 2: Automation in Single-Particle Electron Microscopy

The definition of Automation

“automation is a comprehensive and versatile strategy that can deliver biological information on an unprecedented scale beyond the scope available with classical manual approaches”

Automation in Single-Particle Electron Microscopy: Connecting the Pieces, Lyumkis D, et al. Methods in Enzymology, Volume 483,2010

Page 3: Automation in Single-Particle Electron Microscopy

Website of National Center for Macromolecular Imaging (NCMI)

Automation

Huge number of Particles Demands

Page 4: Automation in Single-Particle Electron Microscopy

Software systems with various degrees of automation and robustness

• AutoEM semi-automated FEI Tecnai series EM

• Leginon advanced automation Philips CM series and FEI Tecnai

• Serial EM automation tomography FEI and JEOL

• TOM Toolbox FEI

• Batch Tomography for cryo-tomography FEI

• JADAS JEOL

James ConwayEPU (FEI version of Leginon)

Susan Hafensein

Page 5: Automation in Single-Particle Electron Microscopy

Outline• General Information• Work flow• Grid Searching• Selective squares on the grid

according to ice thickness

• Centering the holes• Focus and Astigmatism Correction

• Modularity and Flexibility of JADAS• Examples• Speed of data collection

Page 6: Automation in Single-Particle Electron Microscopy

General Information

JADAS JEOL Automated Data Acquisition System (JADAS) software was developed by JEOL collaboration with NCMI Baylor college of Medicine

Developed for current generation of JEOL instruments.Written with C# programming language.Runs only on Windows OS with at least 1GB memory

EPUStands for “E pluribus Unum”, Latin phrase for “out of many, one”

FEI version of LeginonUsing Python programming languageCompatible with both Linux and Windows OS

Page 7: Automation in Single-Particle Electron Microscopy

Work flow

JADAS

Page 8: Automation in Single-Particle Electron Microscopy

Grid Searching

JADAS

100-150X

Page 9: Automation in Single-Particle Electron Microscopy

Grid SearchingLeginon

165X-320X

500-1000 squares

Page 10: Automation in Single-Particle Electron Microscopy

Selective squares on the grid according to ice thickness

The thickness of a vitreous ice layer can be estimated as (Eusemann et al., 1982; Lepault et al., 1982)

t < K ln(I0/I)

I0 is the intensity of a bright-field image in the absence of ice and I is the intensity of the image in the presence of an ice layer of thickness t. K is a constant that is dependent on the geometry of the microscope.

Thickness Range: 500 to 1500 Å

Page 11: Automation in Single-Particle Electron Microscopy

Intensity Based Hole selection GUI automatic local search for JADAS

Page 12: Automation in Single-Particle Electron Microscopy

Ice filter for EPU (Leginon)

Page 13: Automation in Single-Particle Electron Microscopy

Centering the holes

Jadas

Page 14: Automation in Single-Particle Electron Microscopy

Focus and Astigmatism Correction

Ulrike Ziese, Dept. Molecular Cell Biology

Autofocus: beam tilt induced image shift

objective lens

specimen

object plane

objective aperture

image plane

defocus

image shift

optical axis

Page 15: Automation in Single-Particle Electron Microscopy

Ligenon and JADAS can analyze a diffractogram for stigmatism correction also. When the specimen is on a holey carbon film, the software can automatically adjust the objective lens stigmator by measuring the ellipticity of the contrast transfer function rings to correct the astigmatism.

Page 16: Automation in Single-Particle Electron Microscopy

Modularity and Flexibility of JADAS

• Coupling with other tools developed

elsewhere. EMEN2

• integrate image processing function from

EMAN to assess the data quality in real time

• Off-the-shelf remote logon software (e.g.

WebEX: http://www.webex.com/) to monitor

the data

• collection process and even operate JADAS

remotely.

Page 17: Automation in Single-Particle Electron Microscopy

ExamplesJADAS EPU

Page 18: Automation in Single-Particle Electron Microscopy

Speed of data collection

JADAS Using JEM3200FSC, record 30-40 4k×4k CCD images per hour, if each image has 100 particlesOne day: 960 images 96000 particles

EPU

one hour to set up a run for days or weeks,one million particles in a four-daysession on an FEI Titan Krios™ microscope.One day: 250000 particles

Page 19: Automation in Single-Particle Electron Microscopy