Researchers from the United States presented the first high-resolution images of the protein spikes of the coronavirus. Their data will help in the development of therapeutic drugs.
The researchers explained that coronaviruses – the ones that cause COVID-19, for example – have protein spikes. They bind to receptors on the cells of their victims. Scientists have taken the first detailed images of these thorns in their natural state. They are attached to the virus and do not use chemical fixatives that can distort their shape.
They noted that their method, which combines cryogenic microscopy and computation, should produce faster and more realistic images of the infectious apparatus in different strains of the coronavirus. Their research will help develop therapeutic drugs and vaccines.
“The advantage of our imaging is that when you purify the spine protein and study it yourself, you lose an important biological context: what does it look like in an intact virus particle? After all, there may be a completely different structure, ”said Wa Chiu, professor at the SLAC National Accelerator Laboratory. She works for the Department of Education and Science at Stanford University.
At the same time, the virus that causes COVID-19 is so virulent that there are only a few cryo-laboratories in the world that can study it with a sufficiently high level of safety for employees. So for this study, a team of scientists studied a much milder strain of coronavirus called NL63, which causes the common symptoms of the common cold and is responsible for about 10% of respiratory illnesses each year. It attaches to the same receptors on the surface of human cells as COVID-19.
Rather than chemically removing and purifying NL63 proteins, the researchers froze whole, undamaged viruses to a glass state that preserves the natural arrangement of the components. They then took thousands of detailed images of randomly targeted viruses using cryo-EM tools and combined them to produce high-resolution images.