Let us start this post about the virus currently threatening us with a quote from famous military strategist Sun Tzu:

“If you know the enemy and know yourself, you need not fear the result of a hundred battles.” 

Humanity is currently facing an enormous trial in the combined fight against our common “invisible” enemy – the SARS-CoV-2 virus. The wisdom above tells us, that knowing your enemy, in our case – the virus, is key in making a successful and efficient battle.

Our “invisible” enemy is the SARS-CoV-2 virus, also known as novel coronavirus, and is a positive sense single-strand RNA virus from the family Coronaviridiae. An infection with said virus often causes severe acute respiratory syndrome, which puts patients in mortal danger, especially elderly patients with preexisting chronic medical conditions. The virus is very contagious and the cause of the COVID-19 pandemic.


A short but informative video on SARS-CoV-2
SARS-NCOV-2 lifecycle

SARS-CoV-2 enters its host cells endosomatically. (0) First, the viral S protein attaches i to the ACE2 receptor (Angiotenzin Converting Enzyme 2). This is followed by endocytosis, which is how the virus enters the host cell. (1) The virus is first contained in an endosome, which is a tubular membrane structure or follicle inside the cell, which forms from the cellular membrane and is part of intracellular transport. In the next stage, the viral and endosomal membrane fuse, which then leads to the  the decomposition of the endosome. The viral genetic material (+)-RNA is released into the cell. (3) The cell’s ribosomes then read the viral RNA and build polypeptide chains from the “recipe.” (4) Viral protease (3CLPro) then splits the polypeptide chains into smaller proteins. (5) Several non-structural proteins then combine to form replication/transcription complexes (RTK). The most important protein in said complex is RNA dependent RNP polymerase (RdRp), which directly participates in RNA duplication and transcription. The aforementioned complex makes subgenomic (+)RNA fragments, and pregenomic (-)RNA. (5) Pregenomic (-)RNA is responcible for replication, during which genomic (+)RNA is formed. (6) Subgenomic (+)RNA fragments are responsible for forming new copies of viral proteins. (7) Next comes the formation and (8) release of the virus.


To be continued ….