ABOVE: Two models of the SARS-CoV-2 spike protein show the closed receptor binding domain (tan, left) and the open receptor binding domain (tan, right).
ADAPTED FROM A VIDEO BY DONALD BENTON
It’s clear that SARS-CoV-2, the coronavirus behind the COVID-19 pandemic, is most closely related to a group of viruses that usually infect bats. But exactly how and where it evolved to become such an efficient respiratory pathogen remains to be seen. Now, in a study published July 9 in Nature Structural & Molecular Biology, researchers have determined that the spike proteins of SARS-CoV-2 and of the closely related bat coronavirus RaTG13—while similarly structured overall—differ in their stability and affinity for binding ACE2, the receptor that SARS-CoV-2 uses to infect human cells.
The substantial difference in the spike protein of the closest viral relative “tells you that this was not a direct jump from this virus into humans,” says Amesh Adalja, ...
