Brazil Variant, Brazilian lineage, N501Y mutation of SARS-CoV-2 Spike, SARS-CoV-2, coronavirus, SARS-CoV-2 spike RBD, SARS-CoV-2 spike protein, 2019-nCoV, COVID-2019, COVID-19, RBD (N501Y), 501.V2, VUI-202012/01, B.1.1.7, B117, UK Variant, UK lineage, B.
The spike (S) glycoprotein of coronaviruses is essential for binding of the virus to the host cell at the beginning of the infection process. The target protein is also a major immunogen and a possible target for entry inhibitors. The SARS-CoV-2 spike (S) protein is a large type I transmembrane protein composed of two subunits, S1 and S2. The S1 subunit contains a receptor-binding domain (RBD) responsible for binding to the host cell receptor angiotensin-converting enzyme 2 (ACE2). Several mutants of the spike protein are known. A new SARS-CoV-2 lineage called 501Y.V2, also known as lineage B.1.1.7, exhibits several mutations. Compared to the previously circulating variants, the mutation N501Y of SARS-CoV-2 Spike S1 (RBD) results in a significant higher transmissibility. This increase is most likely due to a higher binding affinity of the spike protein to hACE2. Therefore, the N501Y mutation is considered the most dangerous modification of the virus.