We have launched our mobile app, get it now. Call : 9354229384, 9354252518, 9999830584.  

Current Affairs

Changing shape of Coronavirus

Date: 25 July 2020 Tags: Miscellaneous

Issue

Researchers have found that the spike protein in SARS-CoV-19 changes its form after it attaches itself to a human cell, folding in on itself and assuming a rigid hairpin shape.

 

Background

It is a protein that protrudes from the surface of a coronavirus, like the spikes of a crown or corona hence the name ‘coronavirus’.

 

Details

  • In the SARS-CoV-2 coronavirus, it is the spike protein that initiates the process of infection in a human cell. It attaches itself to a human enzyme, called the ACE2 receptor, before going on to enter the cell and make multiple copies of itself.

  • The research shows a dramatic change to the hairpin shape after the spike protein binds with the ACE2 receptor.

  • In fact, the researchers found that the “after” shape can also show itself before fusion — without the virus binding to a cell at all.

  • Assuming the alternative shape may help keep SARS-CoV-2 from breaking down. Studies have shown that the virus remains viable on various surfaces for various periods of time.

  • The post-fusion shape could induce antibodies that do not neutralise the virus. In effect, the spikes in this form may act as decoys that distract the immune system.

  • Antibodies specifically targeting the post-fusion state would not be able to block membrane fusion (viral entry) since it would be too late in the process. 

  • Both the “before” and “after” forms have sugar molecules, called glycans, at evenly spaced locations on their surface. Glycans are another feature that helps the virus avoid immune detection.

  • The researchers believe the findings have implications for vaccine development. Many vaccines that are currently in development use the spike protein to stimulate the immune system.