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bioRxiv · 10.1101/2020.03.13.991570

A highly conserved cryptic epitope in the receptor-binding domains of SARS-CoV-2 and SARS-CoV

Yuan, M.·Wu, N. C.·Zhu, X.·Lee, C.-C. D.·So, R. T. Y.·Lv, H.·Mok, C. K. P.·Wilson, I. A.
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Abstract

The outbreak of COVID-19, which is caused by SARS-CoV-2 virus, continues to spread globally, but there is currently very little understanding of the epitopes on the virus. In this study, we have determined the crystal structure of the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein in complex with CR3022, a neutralizing antibody previously isolated from a convalescent SARS patient. CR3022 targets a highly conserved epitope that enables cross-reactive binding between SARS-CoV-2 and SARS-CoV. Structural modeling further demonstrates that the binding site can only be accessed when at least two RBDs on the trimeric S protein are in the "up" conformation. Overall, this study provides structural and molecular insight into the antigenicity of SARS-CoV-2. ONE SENTENCE SUMMARYStructural study of a cross-reactive SARS antibody reveals a conserved epitope on the SARS-CoV-2 receptor-binding domain.

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Yuan, M., Wu, N. C., Zhu, X., Lee, C.-C. D., So, R. T. Y., Lv, H., Mok, C. K. P., Wilson, I. A.. 2020-03-14. A highly conserved cryptic epitope in the receptor-binding domains of SARS-CoV-2 and SARS-CoV. https://doi.org/10.1101/2020.03.13.991570

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