Biocomputational Analysis of Spike Proteins to Identify Evolutionary Divergence of Beta- CoVs with Focusing on SARS-CoV2

ABSTRACT

Spike (S) proteins covering the outer surface of the Coronaviruses are the major hotspots of evolution and are also responsible for attaching the virus to the angiotensin-converting enzyme (ACE2) receptor on the host cells. In this study, we unveiled the evolutionary relics of the S-protein sequences of different beta Coronaviruses, namely, Severe Acute Respiratory Syndrome (SARS-CoV), SARS-CoV-2, and Middle East Respiratory Syndrome (MERSCoV). The present study aims at exploring the sequence divergence of the spike protein (S-protein) of nCov2 viruses to illuminate the evolutionary process. The nucleotide sequences of S-proteins of nCov2 viruses, namely, SARS, MERS and SARS-CoV2, representing different continents of the world, were downloaded from the NCBI Nucleotide databases. The conserved regions have been depicted through multiple sequence alignment (Clustal Omega, Jalview) and the molecular phylogeny has been studied. (using MEGA 7). Comparative analysis of the pairwise distance and selection pressure indicated that the SARS-CoV and SARS-CoV-2 are close to each other, however, distantly related to MERS-CoV and the SARS-CoV2 could have evolved from SARS (Severe Acute Respiratory Syndrome).