Comparative Sequence Analysis of SARS-CoV-2 Suggests Its High Transmissibility and Pathogenicity

Abstract

Aim: Because the highly pathogenic SARS-CoV-2 is newly introduced to humans, we aimed to understand the unique features of its genome and proteins, crucial for high transmissibility and disease severity. Materials & methods: The available genome and protein sequences of SARS-CoV-2 with known human and nonhuman CoV were analyzed using multiple sequence alignment programs. Results: Our analysis revealed some unique mutations in SARS-CoV-2 spike, ORF1a/b, ORF3a/3b and ORF8. The most interesting ones were in the spike angiotensin-converting enzyme 2 receptor binding-motif and generation of a furin-like cleavage site as well as deletions of ORF3a ‘diacidic motif’ and the entire ORF3b. Conclusion: Our data suggest that SARS-CoV-2 has diverged from SARS-CoV-1 but is most close to bat-SL-CoV. Unique mutations in spike and ORF3a/b proteins strongly endorse its adaptive evolution, enhanced infectivity and severe pathogenesis in humans.

Keywords:

• bat-SL-CoV
• COVID-19
• pathogenesis
• SARS-CoV-1
• SARS-CoV-2
• spike protein

Author contributions

K Padhan and MK Parvez contributed in conceptualization, methodology, software, data analysis and manuscript writing. MS Al-Dosari contributed in data analysis, manuscript writing and editing.

Acknowledgments

The authors thank the Deanship of Scientific Research, King Saud University for funding.

Financial & competing interests disclosure

The authors have received a grant from the Deanship of Scientific Research, King Saud University (Grant no: RG-1435-053). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No funded writing assistance was utilized in the production of this manuscript.