"Automated Cryo-tomography and Single Particle Analysis with the Volta Phase Plate" Radostin Danev Ph.D.

Molecular Cryo-Electron Microscopy Unit (Wolf Unit) would like to invite you to the Seminar by Radostin Danev Ph.D. (Max Planck Institute of Biochemistry).

We are delighted to host Dr. Radostin Danev, who is one of the key developers of the modern phase plate for electron microscopy. He has worked with Prof. Nagayama and then moved on to the Max Planck Institute at Martinsried, where he is a group leader. During his time at the MPI, he collaborated with FEI to create a new type of phase contrasting method, which is currently opening up new applications from cellular tomography to high resolution protein structure. If you want to know what's hot in biological electron microscopy, please come hear his talk!

Date:     Monday, June 15th, 2015
Time:    10:00 – 11:00 am
Venue:  C209, Center Bldg., Level C
Speaker: Radostin Danev Ph.D.

Max Planck Institute of Biochemistry

Title:    "Automated Cryo-tomography and Single Particle Analysis with the Volta Phase Plate"

Abstract:

Recent years have shown an increased interest in the development and use of phase plates in cryo-EM. The oldest and the most productive type of phase plate is the thin film Zernike phase plate. It has been successfully used in cryo-tomography and single particle analysis applications. Despite its good performance the Zernike phase plate has a few pitfalls. One major practical hindrance is its short lifetime. Typically within 10 days after being installed into the microscope its performance deteriorates to the point where it has to be exchanged. Another disadvantage of the Zernike phase plate is that it produces fringes around high-contrast features in the image, such as lipid membranes, support film edges etc. Despite its shortcomings the Zernike phase plate has been the main motivation and experience generator in the last years.

In collaboration with the FEI Company we recently developed a new type of phase plate – the Volta phase plate. It addresses both shortcomings of the Zernike phase plate discussed above. Our tests indicate that the new phase plate lasts for more than six months inside the microscope. This is a big advantage in terms of servicing and up time of the microscope. The other big advantage of the new phase plate is that it produces fringe-free images which resemble in appearance light microscopy phase contrast images.

The Volta phase plate was tested with the two main 3D cryo-EM techniques – cryo-tomography and single particle analysis. Comparing the results with what has been published shows that it performs significantly better than the thin film Zernike phase plate. The improvements are both in image appearance and resolution.

Radostin Danev¹, Yoshiyuki Fukuda¹, Maryam Khoshouei¹, Wolfgang Baumeister¹

^1. Max Planck Institute of Biochemistry, Martinsried, Germany.

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We hope to see many of you at the Seminar.