Spike glycoprotein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (S-protein)

The SARS-CoV-2 spike glycoprotein is a large, homotrimeric transmembrane protein expressed on the surface of the virus, mediating viral entry into host cells by binding to the angiotensin-converting enzyme 2 (ACE2) receptor and driving fusion of the viral and cellular membranes[1][3][7]. Each monomer consists of 1,273 amino acid residues in the original Wuhan-Hu-1 strain[1][5][7]. The protein is composed of S1 and S2 subunits: S1 contains the receptor-binding domain (RBD) responsible for ACE2 recognition, while S2 mediates membrane fusion[1][3][7]. The trimeric spike protrudes from the viral surface, giving the coronavirus its characteristic "crown-like" appearance[1][7]. The spike protein is highly immunogenic and serves as the primary target for vaccine development and antibody therapeutics[3][6]. It is extensively glycosylated and undergoes significant conformational changes upon receptor engagement and host cell entry[3][6]. Mutations in the spike protein are linked to viral evolution, altered transmissibility, and immune escape in emerging variants[3][8].

Other names

Spike proteinS glycoproteinSpike (S) proteinS proteinE2 (historical nomenclature)Coronavirus spike proteinSARS-CoV-2 spike

Antibodies: Block receptor-binding domain (RBD), inhibit S-protein binding to ACE2, neutralize virus entry[1][3][6][7]; Vaccines: Induce neutralizing antibodies against spike antigen, stimulate T-cell responses[1][3][5][6]; Protease inhibitors: Block S-protein priming/fusion activation; Entry inhibitors: Prevent S-protein structural rearrangement or fusion with host cell[6][7]