PubMed:32245784 JSONTXT 11 Projects

A highly conserved cryptic epitope in the receptor-binding domains of SARS-CoV-2 and SARS-CoV. The outbreak of COVID-19 caused by SARS-CoV-2 virus has now become a pandemic, but there is currently very little understanding of the antigenicity of the virus. We therefore determined the crystal structure of CR3022, a neutralizing antibody previously isolated from a convalescent SARS patient, in complex with the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein to 3.1 Å. CR3022 targets a highly conserved epitope, distal from the receptor-binding site, that enables cross-reactive binding between SARS-CoV-2 and SARS-CoV. Structural modeling further demonstrates that the binding epitope can only be accessed by CR3022 when at least two RBD on the trimeric S protein are in the "up" conformation and slightly rotated. Overall, this study provides molecular insights into antibody recognition of SARS-CoV-2.