Scientists received a three-dimensional atomic picture of the virus

© Illustration RIA Novosti . Alina Polarisavenue created a technique that allows to obtain «atomic» pictures of virusesScientists received a three-dimensional atomic picture of the virus© Illustration RIA Novosti . Alina Polyanina

. Investigators were able to obtain the first complete atomic picture of the virus, developing the technique of ultrafast x-ray three-dimensional biological materials using x-ray, according to a paper published in the journal Nature Methods.

«Understanding how to construct three-dimensional protein molecule or any other substance, allows us to reveal the role it plays in the cells and body. For example, the structure of a protein «grappling hook» of the virus, by which it attaches to the cell membrane, can help us to protect the cell from its penetration,» says David Stewart (David Stuart) from the University of Oxford (UK).

Complex protein molecules in our bodies consist of several thousand amino acids, whose chains are often twisted in a complex shape due to the interactions between the individual links of these peptide chains. Biologists do not yet fully revealed the laws by which proteins adopt a certain form and which allow you to learn the shape of a molecule by its formula.

Therefore, the structure of individual proteins, scientists have to determine «manually» or using computer simulation, or freezing of the protein molecules with the help of liquid nitrogen and helium, «prosvetova» their heavy duty x-ray lasers.

As Stuart says, the scientists quite a long time trying to adapt this technique to obtain the «atomic» pictures of individual cells, bacteria and viruses. All attempts to obtain such images were failed for the reason that living organisms are quite difficult to freeze without destroying it, and the x-rays quickly destroy the molecules on their surface and does not allow to obtain high quality three-dimensional images of the whole microbe or virus.

To solve this problem Stuart and his team created a new method of photographing a virus, which they called serial crystallography. The main distinction from conventional x-ray crystallography is that it does not require refrigeration of test samples and is therefore at room temperature.

Its key part is a special silicon plate with a large number of pores, the dimensions of which are selected so that the virus particles get stuck in them and lose their mobility. Prospecive each such trap with a x-ray laser, scientists can obtain data on the atomic structure of the portion of the virus, which «Peeps» out of the pores, and combine them to obtain the full three-dimensional images.

Such an approach, Stewart says, allowed his team to get pictures of BEV2 virus affecting cattle and causing miscarriages, spending just 14 minutes of time on the «translucence» of the chip using superpower x-ray laser LCLS, established in the American National accelerator centre SLAC.

Each pixel in the picture, which was received by Stewart and his colleagues, takes only 0.23 nm, which allows to see individual atoms and groups of molecules on the surface of the shell of the virus inside her.

In the near future, physicists plan to increase the number of pores in the plate ten times and adapt the methodology to work with larger and more complex viruses. In addition, the use of the European XFEL, capable of producing up to 27 thousand powerful, but short pulses of x-rays per second, will allow to obtain such three-dimensional images even faster than before, which will accelerate the search for vaccines and drugs against HIV and other viral diseases.