Fig. 1.

Representation of the genomic organization of the SARS-CoV-2 and domain structure of Spike glycoprotein (A). S-glycoprotein contains S1 and S2 subunits where S1 subunit consists of signal sequence, N-terminal domain (NTD) and receptor binding domain (RBD). The S2 subunit consists of heptad-repeat (HR) regions as HR-N and HR-C involves the formation of coiled coil structure within the protein ectodomain. At the interface of S1 and S2 subunit various cleavage sites are present including protease, furin and S2′ protease. S- Spike glycoprotein gene, E-Envelope protein gene, N- nucleocapsid protein gene, M- membrane protein gene, RBD- receptor-binding domain. Structural comparison of Spike glycoprotein of SARS-CoV-2 (B), with SARS-CoV (C), suggesting minimal structural difference in superimposed spike glycoproteins structures (D)