A Comparison of the Evolution, Structure, and Function of SARS-CoV and SARS-CoV-2 Spike Proteins

As the COVID-19 pandemic has developed into the largest pandemic of the twenty-first century, it has become apparent that this disease, caused by the SARS-CoV-2 virus, is unlike anything the modern world has faced before. Not only has the disease infected more than 16 million people worldwide, but its rapid spread has drawn global attention to the gaps in our understanding of its pathogenesis and the development of vaccines and treatments. One of the most important topics of research in the disease is the viral spike (S) protein which facilitates binding and entering host cells and plays a key role in host specificity and pathogenicity among others. This review attempts to capture the importance of S protein in this new disease through evolutionary, structural, and functional lenses while drawing parallels to the recent SARS-CoV outbreak to identify what has made COVID-19 so different