What has emerged from 19 months of work, backed by decades of coronavirus research, is a blow-by-blow account of how SARS-CoV-2 invades human cells (see ‘Life cycle of the pandemic coronavirus’). By picking apart the infection process, they hope to find better ways to interrupt it through improved treatments and vaccines, and learn why the latest strains, such as the Delta variant, are more transmissible. Since the start of the COVID-19 pandemic, scientists have been developing a detailed understanding of how SARS-CoV-2 infects cells. It’s possible that snipping out those two sugars could reduce the virus’s infectivity, says Amaro, although researchers don’t yet have a way to do this. McLellan’s team built a way to try the same experiment in the lab, and by June 2020, the collaborators had reported that mutating the two glycans reduced the ability of the spike protein to bind to a human cell receptor 1 - a role that no one has previously recognized in coronaviruses, McLellan says. When Amaro mutated the glycans in the computer model, the RBD collapsed. In Amaro’s simulation, when the RBD lifted up above the glycan cloud, two glycans swooped in to lock it into place, like a kickstand on a bicycle. ![]() Source: Structural image from Lorenzo Casalino, Univ. But ten minutes later, structural biologist Jason McLellan at the University of Texas at Austin chimed in: the uncoated loop was a receptor binding domain (RBD), one of three sections of the spike that bind to receptors on human cells (see ‘A hidden spike’). Within an hour, one researcher asked in a comment: what was the naked, uncoated loop sticking out of the top of the protein?Īmaro had no idea. On 22 March 2020, she posted the simulation to Twitter. But last year, Amaro’s laboratory group and collaborators created the most detailed visualization yet of this coat, based on structural and genetic data and rendered atom-by-atom by a supercomputer. ![]() Many viruses have glycans covering their outer proteins, camouflaging them from the human immune system like a wolf in sheep’s clothing. ![]() “When you see it with all the glycans, it’s almost unrecognizable,” says Amaro, a computational biophysical chemist at the University of California, San Diego. It was swathed in sugar molecules, known as glycans. “It’s striking,” thought Rommie Amaro, staring at her computer simulation of one of the trademark spike proteins of SARS-CoV-2, which stick out from the virus’s surface. The coronavirus sports a luxurious sugar coat. A computer simulation of the structure of the coronavirus SARS-CoV-2.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |