A new coronavirus outbreak has emerged in Wuhan, China, in 2019 and
turned into a global pandemic posing a massive public health concern. Its genome has
been sequenced and showed pairwise percent identities of approximately 79.5% and
50% compared to severe acute respiratory syndrome-coronavirus (SARS-CoV) and the
Middle East respiratory syndrome-coronavirus (MERS-CoV), respectively. The
coronavirus spike glycoprotein is the primary determinant of viral tropism and is
responsible for receptor binding and membrane fusion. The receptor-binding domain of
severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has been
characterized and structurally identified through X-ray crystallography and cryoelectron
microscopy. The variations in residual sequences, hidden receptor binding
domain, and furin-like cleavage nature of the spike clarified the higher receptor affinity
and efficient spread among humans compared to SARS-CoV. The spike glycoprotein is
a vital target for vaccines and therapeutic antibodies. Correspondingly, the potential
implication of its structure elucidation in developing new and cross-neutralizing
antibodies targeting the spike epitopes has been briefly discussed. Here, it is expected
that the elaborated details of the molecular structure may facilitate the opportunity of
developing therapeutics against SARS-CoV-2.
Keywords: COVID19, Crystal structure, Neutralizing antibody, Receptor
binding domain, SARS-CoV-2, Spike glycoprotein, Vaccine.
