The SARS-CoV-2 Spike (S) glycoprotein mediates the entry of the virus into target cells via its interaction with the angiotensin-converting enzyme 2 (ACE2) receptor, thereby initiating the infection. It forms a homotrimeric structure on the surface of the SARS-CoV-2 virus and represents the major target for diagnostic and therapeutic agents. The ectodomain of the S glycoprotein comprises the N-terminal S1 subunit, including the receptor binding domain, and, the C-terminal S2 subunit.
The SARS-CoV-2 Spike-Prot (HEK) protein covers the ectodomain of the viral surface protein including amino acids V16 to K1211 and contains the stabilizing proline substitutions at position K986P and V987P as well as a mutated