Suchergebnisse

The IV Russian International Conference on Cryo-Electron Microscopy (RICCEM-2023) was held at the Faculty of Biology of Lomonosov Moscow State University in a hybrid (offline and online) format and brought together more than 250 researchers from 10 countries. Following the conference, a special issue of the journal "Lomonosov Biology Journal" ("Vestnik Moskovskogo universiteta. Seria 16. Biologia") was published. This article briefly summarizes the main results of the conference and the content of the works published in the special issue.

This paper demonstrates an example of a successful upgrade of a JEOL JEM-2100 analytical
transmission electron microscope to a low-resolution cryo-electron microscope designed for
routine tasks of sample preparation and quality evaluation. As a result of the upgrade, the instrument allows the subnanometer resolution of protein molecule reconstructions (within 8 Å).
The influence of graphene and amorphous carbon support films to prevent the effect of preferred
orientation of protein particles in the frozen sample is discussed.

A detergent-free protocol for purification of the coronavirus prefusion S-protein using styrene-
maleic acid copolymer (SMA) was developed. Expression of the S-protein was carried out in
HEK293T cells. Two solubilization methods were used to purify and prepare the S-protein for
microscopy: in NP-40 detergent and as part of SMA. The resulting preparations were examined
in an electron microscope, and the particles of purified S-proteins were classified. Analysis of
two-dimensional projections of the particles showed that the use of lipodiscs for solubilization
leads to lower mobility of the purified protein on the substrate, compared to the protein in the
detergent, which may further contribute to obtaining higher resolutions when studying the
structure of membrane proteins.