Scientists discover new vulnerability in coronavirus

Scientists have uncovered a new vulnerability in the spike protein of the novel coronavirus, which enables the virus to enter host cells, an advance that may lead to potential treatment pathways against COVID-19.

The researchers, including those from Northwestern University in the US, noted that the spike protein contains the virus’ binding site, which adheres to host cells and enables it to enter and infect the body.

In the study, they used simulations of this protein at ultrasmall scales, in the order of nanometres, and discovered a positively charged site – known as the polybasic cleavage site – located 10 nanometers from the actual binding site on the spike protein.

They said this positively charged site allows strong bonding between the novel coronavirus SARS-CoV-2’s spike protein and the negatively charged human-cell receptors. Leveraging this discovery, the scientists then designed a negatively charged molecule to bind to the positively charged cleavage site. They said blocking this site inhibits the virus from bonding to the host cell.

“Our work indicates that blocking this cleavage site may act as a viable prophylactic treatment that decreases the virus' ability to infect humans,” said Monica Olvera de la Cruz, a coauthor of the study from Northwestern University. “Our results explain experimental studies showing that mutations of the SARS-CoV-2 spike protein affected the virus transmissibility,” she said. Made up of protein building blocks, the amino acid molecules, the polybasic cleavage sites in the novel coronavirus have remained elusive since the COVID-19 outbreak began, the researchers said.