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  • 20 April, 2020

  • 2 Min Read

Polyprotein – Virus and Bacteria

Polyprotein – Virus and Bacteria

Difference between Coronavirus and bacterium:



Bacteria are living even outside a host body.

The viruses are basically inactive outside a host organism.

Each bacterial cell has its own machinery to reproduce itself.

Viruses would be unable to renew and grow by themselves.

The genes in the Bacterial cells are made up of DNA molecules.

The Coronavirus does not have DNA as their genome, but instead has RNA. (Some viruses also have DNA as their genetic material)

The information contained in this DNA is transcribed as a message to the messenger molecules called RNA. This message is translated into action molecules called proteins which help in the growth and multiplication of the bacterium.

The Corona viruses can only translate and not transcribe. The viruses infect the ‘host cells’ which they bind to, and multiply.

Drug strategy:

  • Upon infection, the entire RNA of the Virus with its 33,000 bases is translated into a long tape of amino acid sequences. Since this long chain contains several proteins within it, it is called a “polyprotein” sequence.
    • COVID19 has RNA-based genomes and subgenomes in its polyprotein sequence, that code for the spike protein (S), the membrane protein (M), the envelope protein (E), and the nucleocapsidprotein (N, which covers the viral cell nuclear material) – all of which are needed for the architecture of the virus.
    • In addition to these, there are special structural and accessory proteins, called non-structural proteins (NSP), indeed 16 of them, which serve specific purposes for infection and viral multiplication.
  • A detailed understanding of these proteins can help the scientific community find relevant proteins and understand their effect on Virus functioning and infection.
  • These proteins in the virus can be targeted by a number of potential molecules and drugs which can interfere and stop the production of the viral proteins.

Source: TH/WEB

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