SARS-CoV-2 spike glycoprotein receptor-binding domain (Delta variant) (RBD (Delta variant))

The SARS-CoV-2 spike glycoprotein receptor-binding domain (RBD) of the Delta variant (B.1.617.2) is a critical viral protein domain that mediates host cell infection by binding to the human angiotensin-converting enzyme 2 (ACE2) receptor [1.1.1, 1.1.3]. Located within the S1 subunit of the spike protein, the RBD undergoes conformational changes to an 'up' position to become accessible for receptor docking [1.4.2]. The Delta variant is distinguished by specific mutations in this domain, notably L452R and T478K, which enhance its binding affinity to ACE2 and contribute to the variant's increased transmissibility and ability to evade certain neutralizing antibodies [1.3.1, 1.3.3]. As the primary target for most COVID-19 vaccines and therapeutic monoclonal antibodies, the RBD is essential for inducing protective immunity and serves as the site of action for drugs that block viral entry [1.2.3, 1.5.2]. However, the emergence of these mutations has historically led to reduced efficacy for several early-authorized monoclonal antibody treatments [1.2.5, 1.4.1]. Consequently, the Delta RBD remains a focal point for structural studies and the development of next-generation, broad-spectrum antiviral strategies [1.3.5, 1.5.5].

Other names

B.1.617.2 RBDDelta variant RBDSARS-CoV-2 S1-RBD (Delta variant)Spike RBD (Delta variant)

Neutralization of viral entry by blocking the interaction between the viral receptor-binding domain and the host angiotensin-converting enzyme 2 (ACE2) receptor.