Exploration of antigenic determinants in spike glycoprotein of SARS-CoV2 and identification of five salient potential epitopes

Emerging pathogens have been an eternal threat to mankind. In a series of pandemics caused by notorious coronaviruses, a newly emerged SARS-CoV2 virus is creating panic among the world population. The unavailability of reliable theranostics insists the exploration of antigenic determinants in spike glycoprotein of SARS-CoV2. The four novel inserts (‘⁷⁰VSGTNGT⁷⁶’, ‘¹⁵⁰KSWM¹⁵³’, ²⁴⁷SYLTPG²⁵² and ⁶⁷⁴QTQTNSPRR⁶⁸²) in SARS-CoV2 spike protein were unraveled via multiple sequence alignment of spike proteins of SARS-CoV2, SARS-CoV, and MERS-CoV. The three-dimension (3D) modeling of the spike protein of the SARS-CoV2 and their interaction with the ACE2 receptor was delineated with the help of SWISS-MODEL and 3DLigandSite web servers. The predicted 3D model of SARS-CoV2 was further verified by SAVES, RAMPAGE, and ProSA-web tools. The potential B-cell immunogenic epitopes of SARS-CoV2 were predicted out by using various software viz. IEDB B-cell epitopes prediction tool, BepiPred linear epitope prediction tool, Emini Surface Accessibility Prediction tool, and Kolaskar-Tongaonkar antigenicity web tool. The five epitopes (i.e. ‘⁷¹SGTNGTKRFDN⁸¹, ²⁴⁷SYLTPG²⁵², ⁶³⁴RVYST⁶³⁸, ⁶⁷⁵QTQTNSPRRARSV⁶⁸⁷, and ¹⁰⁵⁴QSAPH¹⁰⁵⁸) were selected as potent antigenic determinants. The quantum of information generated by this study will prove beneficial for the development of effective therapeutics, diagnostics, and multi-epitopic vaccines to combat this ongoing menace.