Automated Particle Picking based on Correlation Peak Shape Analysis and Iterative Classification

Cryo-electron microscopy (CEM) in combination with single particle analysis (SPA) is a widely used technique for elucidating structural details of macromolecular assemblies at closeto- atomic resolutions. However, development of automated software for SPA processing is still vital since thousands to millions of individual particle images need to be processed. Here, we present our workflow for automated particle picking. Our approach integrates peak shape analysis to the classical correlation and an iterative approach to separate macromolecules and background by classification. This particle selection workflow furthermore provides a robust means for SPA with little user interaction. Processing simulated and experimental data assesses performance of the presented tools.

Authors:

• Hrabe Thomas
• Beck Florian
• Nickell Stephan

Keywords:

• Cryo-electron Microscopy
• Single Particle Analysis
• Image Processing.

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