Semmelweis University’s research team and the staff of the National Security Laboratory were the first ones to investigate the structure of an active and infectious coronavirus.
The virus might be one of the most resilient biological organisms based on the results, because it is self-healing and the spikes on the surface of the pathogen are very mobile, reported 24.hu. The virus was shown to be efficiently compressed; however, it will restore its shape, much like a rubber ball, and its structure will remain intact.
Experts have been studying SARS-CoV-2, more commonly referred to as coronavirus, since it was discovered. Still, many of their questions remain unanswered about the pathogen. A team led by the Dean of the Faculty of General Medicine at Semmelweis University, Dr Miklós Kellermayer, and researchers of the National Safety Laboratory of the National Center of Public Health studied the structure of the coronavirus together. They used an atomic force microscope to scan the surface of the virus’s particles. Dr Kellermayer stated that the mechanical and self-healing abilities of the virus could be the reason behind its high infectivity, as it can easily adapt to many different environmental conditions.
Dr Kellermayer and his team studied active and infectious coronavirus samples, which is quite unique, as all the existing researches beforehand were done on inactivated and chemically treated or frozen samples. Their research could be conducted because of Semmelweis University’s atomic force microscope (AFM), which is used to study the topographic structures and nanomechanical properties of atoms, molecules and cells, as well as a protocol which was developed for their measurements.
The Hungarian researchers pierced and approximately 80-nanometer wide coronavirus particle by using an even smaller needle, to press from the top to the bottom of the virus, causing it to compress. However, the virus just bounced back to its standard form immediately after the needle was removed. The team tried this a hundred times on the same organism, but it remained intact each time. This could be proof of SARS-CoV-2 being one of the most resilient viruses.
The properties of the structure of the organism were also studied. The team found, that while most viruses become vulnerable without a host, the new coronavirus has the ability to remain infectious for a long time even on the surface of objects. The mobility of the spikes on the pathogen could be helpful in this.
There may be more variables of the virus structure than currently estimated, as the number of spikes on the surface of the virus has differed in many studies, for example, the University of Cambridge found around 24, the Max Planck Institute around 40, while the Hungarian researchers counted 61 on the organism they studied.
The AFM can take 300 images per second; however it was still only able to make a blurred image of the spikes, as they swung on a high frequency under the impact of the needle. According to the researchers, this high speed may allow the virus to find host cells and connect to them more easily.
While studying the virus’s thermal resistance, they found that it only loses a few spikes after being exposed to 90°C for 10 minutes, while its structure remains unharmed. This could be the explanation for it remaining infectious despite the summer heat.