Study reveals Covid virus' "cunning" tactics of being so contagious

London: Scientists from Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland have found the cunning strategy of Covid-19 to be so infectious. The team focussed on SARS-CoV-2, the Covid-19 virus’s spike protein, which allows it to enter and infect human cells, reports IANS.

The team found out that SARS-CoV-2 manipulates the host’s cellular machinery to modify an enzyme that then turbocharges the spike's ability to invade other cells. The enzyme, under the abbreviation ZDHHC20, tags proteins with a little fat molecule that changes the way they work. Upon infection, the virus takes over the ZDHHC20 enzyme, the study revealed.

In the study, published in the journal Nature Communications, Gisou van der Goot of EPFL's School of Life Sciences said, "In our previous work, we discovered the enzyme that modifies the SARS-CoV-2 spike protein -- it adds lipids to it -- and this is essential for the virus to fuse with target cells”.

"What we now show is that the virus triggers an optimisation of the enzyme by inducing a change in the transcription of its gene," van der Goot added.

The research team found out, after analysing the effects of SARS-CoV-2 on the gene (zdhhc20) that, the virus triggers a change in its transcriptional start site -- the part of a gene where the process of "reading" it into a protein begins.

This "transcriptional change" produces an enzyme with 67 additional amino acids. This is enough to increase its lipid-adding activity on the spike 37 times, leading to a heavily enhanced viral infectivity, the report suggested.

To get a comprehensive view of the virus's manipulative tactics the team used tests like metabolic labelling, Western blotting, and immunofluorescence. SARS-CoV-2 hijacks a pre-existing cell damage response pathway to generate more infectious viruses, the team found.