SARS-CoV-2 spike protein receptor-binding domain – Angiotensin-converting enzyme 2 interface (SARS-CoV-2 RBD–ACE2 interface) (SARS-CoV-2 RBD–ACE2 interface)

The SARS-CoV-2 spike protein receptor-binding domain (RBD) – Angiotensin-converting enzyme 2 (ACE2) interface is the critical molecular gateway for the entry of the SARS-CoV-2 virus into human host cells (Lan et al., 2020, Nature). The spike protein, located on the viral surface, utilizes its RBD to specifically recognize and bind to the peptidase domain of ACE2, which is highly expressed in the lungs, heart, and other tissues (Shang et al., 2020, Nature). This high-affinity interaction triggers a series of conformational changes in the spike protein, leading to the fusion of the viral and host cell membranes (UniProt P0DTC2). Because this interface is essential for infection, it has become a primary focus for the development of vaccines and therapeutic interventions (NIH, 2021). Monoclonal antibodies, such as Bamlanivimab and Sotrovimab, are designed to bind to the RBD, sterically hindering the formation of the complex and neutralizing the virus's ability to infect cells (FDA, 2022). However, the rapid evolution of the virus has led to mutations within the RBD, such as N501Y and E484K, that can enhance binding affinity or allow the virus to evade existing immune responses and therapeutic antibodies (Harvey et al., 2021, Nature Reviews Microbiology). Understanding the structural and biochemical properties of this interface is vital for the ongoing development of next-generation therapeutics and vaccines that remain effective against emerging variants of concern.

Other names

SARS-CoV-2 RBD-ACE2 complexSpike-ACE2 interaction siteS-RBD/ACE2 interfaceSARS-CoV-2 S-protein RBD-ACE2 interface

The primary mechanism of action involves the competitive inhibition of the protein-protein interaction between the viral receptor-binding domain (RBD) and the host Angiotensin-converting enzyme 2 (ACE2) receptor. Neutralizing monoclonal antibodies bind to specific epitopes on the RBD, sterically blocking its ability to engage with ACE2, thereby preventing viral attachment and subsequent entry into the host cell (Lan et al., 2020, Nature; FDA, 2022).