Recent emergence of SARS-CoV-2 and associated COVID-19 pandemic have posed a great challenge for the scientific community. In this study, we performed bioinformatic analyses on SARS-CoV-2 protein sequences, trying to unravel potential molecular similarities between this newly emerged pathogen with non-coronavirus ssRNA viruses. Comparing the proteins of SARS-CoV-2 with non-coronavirus positive and negative strand ssRNA viruses revealed multiple sequence similarities between SARS-CoV-2 and non-coronaviruses, including similarities between RNA-dependent RNA-polymerases and helicases (two highly-conserved proteins). We also observed similarities between SARS-CoV-2 surface (i.e. spike) protein with paramyxovirus fusion proteins. This similarity was restricted to a segment of spike protein S2 subunit which is involved in cell fusion. We next analyzed spike proteins from SARS-CoV-2 “variants of concern” (VOCs) and “variants of interests” (VOIs) and found that some of these variants show considerably higher spike-fusion similarity with paramyxoviruses. The ‘spike-fusion’ similarity was also observed for some pathogenic coronaviruses other than SARS-CoV-2. Epitope analysis using experimentally verified data deposited in Immune Epitope Database (IEDB) revealed that several B cell epitopes as well as T cell and MHC binding epitopes map within the spike-fusion similarity region. These data indicate that there might be a degree of convergent evolution between SARS-CoV-2 and paramyxovirus surface proteins which could be of pathogenic and immunological importance.
【초록키워드】 viruses, Evolution, SARS-CoV-2, COVID-19 pandemic, variant, Proteins, Spike protein, Helicase, Protein, T cell, pathogen, VOCs, Scientific community, VOIs, MHC, Analysis, B cell epitope, similarity, subunit, IEDB, sequence similarity, pathogenic, SARS-CoV-2 protein, positive, ssRNA, surface protein, Immune Epitope Database, recent, immunological, Cell, spike protein S2, analyzed, performed, virus, involved, analysis, binding epitope, pathogenic coronavirus, potential molecular, 【제목키워드】 bioinformatics, SARS-CoV-2 spike protein, sequence similarity,