Effect of SARS-CoV-2 B.1.1.7 mutations on spike protein structure and function.
Yang, T.J., Yu, P.Y., Chang, Y.C., Liang, K.H., Tso, H.C., Ho, M.R., Chen, W.Y., Lin, H.T., Wu, H.C., Hsu, S.D.(2021) Nat Struct Mol Biol 28: 731-739
- PubMed: 34385690 
- DOI: https://doi.org/10.1038/s41594-021-00652-z
- Primary Citation of Related Structures:  
7EDF, 7EDG, 7EDH, 7EDI, 7EDJ, 7EH5 - PubMed Abstract: 
The B.1.1.7 variant of SARS-CoV-2 first detected in the UK harbors amino-acid substitutions and deletions in the spike protein that potentially enhance host angiotensin conversion enzyme 2 (ACE2) receptor binding and viral immune evasion. Here we report cryo-EM structures of the spike protein of B.1.1.7 in the apo and ACE2-bound forms. The apo form showed one or two receptor-binding domains (RBDs) in the open conformation, without populating the fully closed state. All three RBDs were engaged in ACE2 binding. The B.1.1.7-specific A570D mutation introduces a molecular switch that could modulate the opening and closing of the RBD. The N501Y mutation introduces a π-π interaction that enhances RBD binding to ACE2 and abolishes binding of a potent neutralizing antibody (nAb). Cryo-EM also revealed how a cocktail of two nAbs simultaneously bind to all three RBDs, and demonstrated the potency of the nAb cocktail to neutralize different SARS-CoV-2 pseudovirus strains, including B.1.1.7.
Organizational Affiliation: 
Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.