Deconstructing SARS-CoV-2 virus

Context:

The novel coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 virus) has affected more than half a million people across the globe.

About:

• SARS coronavirus (SARS-CoV) – virus was identifi ed in 2003. SARS-CoV is thought to be an animal virus from an animal reservoir, perhaps bats, that spread to other animals (civet cats).
• It first infected humans in the Guangdong province of southern China in 2002. How RBD facilitates the virus?
• SARS-CoV-2 has spike proteins that contain a receptor-binding domain (RBD).
• The RBD facilitates the virus’ entry into target cells by binding with the angiotensin-converting enzyme-2 (ACE-2) found in the heart, lungs, kidneys, and the gastrointestinal tract.
• The mutation (if any) increases the RBD’s bonding affinity with the ACE-2 of target cells in humans, ferrets, and Malayan Pangolins.
• This bonding is stronger in the SARS-CoV-2 virus than it was in the SARS-CoV virus, which caused the SARS [Severe Acute Respiratory Syndrome] epidemic in 2002-2003.
• The stronger binding affinity partly explains CoVID-19’s faster spread.

What is spike protein?

• The presence of S proteins on the coronavirus is what gives rise to the spike-shaped protrusions found on their surface.
• S proteins of coronavirus can be divided into two important functional subunits, which include the N-terminal S1 subunit, which forms the globular head of the S protein, and the C-terminal S2 region that forms the stalk of the protein and is directly embedded into the viral envelope.