​Cryomicroscopy for macromolecular structure determination

The first Interdisciplinary Training Webinar covers the following topics:
– dose problem in electron microscopy
– cryomicroscopy sample preparation
– protein structure determination in microbiology
– cryomicroscopy imaging
– computer-assisted structural reconstruction
– phase plate use in cryomicroscopy.

The webinar provides other scientists with an introduction to the techniques and applications of cryomicroscopy to the study of biological systems. Cryomicroscopy is done in a specially modified transmission electron microscope, which allows the quick transfer of specially frozen samples into the microscope column, and their subsequent imaging.
The talk explains the use of Volta phase plates, which allow one to convert the phase variation that the sample imparts to the electron beam into an amplitude variation, which is directly observable as an image. The webinar also illustrates the equipment and techniques that are used in order to prepare and then flash-freeze the liquid solution containing the molecules that are to be studied in the cryo electron microscope. It is important that the solution ends up as vitrified ice, as the amorphous structure of such glass-like ice greatly aids the imaging of the molecules.
The talk also highlights molecules and systems of interest, as well as problems that could be addressed by improving physical techniques.
The chief aim of this webinar is to function as primer on cryoTEM. It also aims to initiate the transfer of knowledge from biochemists specialised in cryomicroscopy to the physicists community of Q-SORT, as well as to the physics community at large.

About the speaker

Raimond Ravelli is a structural biologist specialised in X-ray crystallography and electron microscopy. After his study (chemistry, cum laude, 1992) and PhD (1998), he moved to the European Molecular Biology Laboratory (Grenoble outstation) where he became team leader as well as principal beamline scientist on world’s first third-generation multiple wavelength anomalous dispersion beamline ID14-4 at the European Synchrotron Radiation Facility. Catalysed by a NWO personal career grant (Vidi, 2007), he moved back to the Netherlands as assistant professor in electron microscopy. In 2014, he started at the Maastricht University to help set up the new Institute of Nanoscopy. He employs physics, chemistry, engineering and informatics to study biological structures at the highest possible resolution and develops new methods for structure determination. He determined a wide variety of macromolecular structures and complexes, including proteins involved in neurotransmission, cytoskeletal components, viral infection, and protein secretion. He developed both hard- and software to streamline the process of automated data collection and processing on both X-ray crystallography beamlines as well as the electron microscope. His large-scale electron microscopic images have been displayed at the museum Boijmans van Beuningen in Rotterdam (temporary exhibition Science and Art) and Naturalis Biodiversity Museum in Leiden (permanent exhibition), and have been included in the Guinness World Records book as largest digital recording (2013). He (co-)authored almost 100 peer-reviewed scientific papers (cited ~7100  times, H index of 43). He is scientific referee of numerous journals, member of numerous national and international advisory committees, chairman of the Dutch crystallography association, and (co-)organizer of numerous national and international meetings and workshops.