ABSTRACT
The Covid-19 pandemic has swept across the world, causing a never seen burden on our health care systems and challenging biomedical research to give appropriate answers to the epidemic. Modern, one-particle biophysical methods ensure special insight to the characteristics of the cause of the epidemic, the SARS-CoV-2. The virus carries a crown-like layer of spike proteins, which plays a fundamental role in the process of infection. The topography structure and mechanical characteristics of native virions have been determined by atomic force microscopy. Spike proteins form a dynamic surface due to their flexibility and motility. Virions are surprisingly resistant to mechanical compression, and their structure is able to recover after mechanical perturbation. The global structure of the virus is resistant to heat effect, but spike proteins dissociate from the surface with higher temperatures. The mechanical and dynamic characteristics of SARS-CoV-2 contribute to its virulence. The applied one-particle biophysical methods play an important role in understanding and fighting with the more common virus infections. © 2022 Literatura Medica Publishing House. All rights reserved.
ABSTRACT
SARS-CoV-2, the virus responsible for the current COVID-19 pandemic, displays a corona-shaped layer of spikes which play a fundamental role in the infection process. Recent structural data suggest that the spikes possess orientational freedom and the ribonucleoproteins segregate into basketlike structures. How these structural features regulate the dynamic and mechanical behavior of the native virion are yet unknown. By imaging and mechanically manipulating individual, native SARS-CoV-2 virions with atomic force microscopy, here, we show that their surface displays a dynamic brush owing to the flexibility and rapid motion of the spikes. The virions are highly compliant and able to recover from drastic mechanical perturbations. Their global structure is remarkably temperature resistant, but the virion surface becomes progressively denuded of spikes upon thermal exposure. The dynamics and the mechanics of SARS-CoV-2 are likely to affect its stability and interactions.