SARS-CoV-2 spike protein receptor-binding domain (Beta variant) (RBD (B.1.351))

The SARS-CoV-2 spike protein receptor-binding domain (RBD) of the Beta variant (B.1.351) is a critical portion of the viral S1 subunit responsible for mediating infection by docking with the human Angiotensin-Converting Enzyme 2 (ACE2) receptor (UniProt: P0DTC2). This variant, first identified in South Africa, contains three key mutations in the RBD: K417N, E484K, and N501Y (PubMed: 33649065). The N501Y mutation increases the binding affinity to ACE2, while the E484K mutation is primarily associated with significant immune escape, reducing the effectiveness of neutralizing antibodies produced by prior infection or early-wave vaccines (Nature: 593, 110–115). As a therapeutic target, the Beta RBD has been the focus of monoclonal antibody (mAb) development, though several early mAbs like bamlanivimab lost clinical utility against this variant (NIH: COVID-19 Treatment Guidelines). Interacting drugs typically function by sterically hindering the RBD-ACE2 interface, preventing viral entry into respiratory host cells (Science: 372, 6544). Monitoring the mutations within this domain is vital for developing updated booster vaccines and ensuring the continued efficacy of antiviral biologicals (PubMed: 34059617).

Other names

SARS-CoV-2 RBD B.1.351501Y.V2 receptor-binding domainSpike protein S1 subunit RBD (Beta variant)B.1.351 spike RBD

Inhibition of viral entry by competitively binding to the RBD, thereby blocking its interaction with the human Angiotensin-Converting Enzyme 2 (ACE2) receptor.