The novel coronavirus, SARS-CoV-2, is closely related to the SARS virus that caused devastation in 2002-03. A University of Minnesota team, led by researcher Fang Li, studied how mutations that changed the structure of a SARS-CoV-2 protein enabled it to attach more securely to human cells than its predecessor, infect human cells better, and spread faster.
“In general, by learning what structural features of viral proteins are most important in establishing contact with human cells, we can design drugs that seek them out and block their activity—like jamming their radar,” says Li, a professor in the Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine.
The work is published in the journal Nature.
How infection works
During infection, a “spike” protein on the surface of a SARS-CoV-2 particle attaches itself to a human “receptor” protein on the surfaces of human cells—notably lung cells. The receptor “receives” the virus, much as a lock receives a key.
The researchers discovered that just a few mutations had made a molecular “ridge” in the spike protein more compact than a similar structure in the 2002-03 virus. This and other changes helped SARS-CoV-2 attach more strongly to the receptor.
Next, the research team plans to use structural information from this study to develop antibody drugs and vaccines that specifically target the binding of SARS-CoV-2 to its human receptor.
The team also uncovered genetic evidence that bats may be the source of SARS-CoV-2, either directly or with pangolins—a type of scaly anteater—acting as intermediate hosts for the virus.
