Proteomic basis
of antigenic shift of Coronavirus from animal to human hosts
Khaneja Poorna, Angel Annette, Angel Bennet, Joshi Vinod and Buvvaji Mohammed Shareef
Res. J. Biotech.; Vol. 20(2); 134-139;
doi: https://doi.org/10.25303/202rjbt1340139; (2025)
Abstract
Coronaviruses are RNA viruses which were first identified as chicken infections
way back in the year 1920 from North America. Of the seven Human Coronavirus species,
three viz. SARS-CoV-1, MERS-CoV and SARS-CoV-2 have caused severe diseases. Low
titre of neutralizing antibodies was seen in case of SARS-COV-2 as found in the
previous infection of 2002-2003 i.e. SARS-CoV-1. When the genome profile of the
current SARS-CoV-2 was compared with the older strains, it showed forty percent
similarity with the MERS CoV. This indicates that origin of SARS-CoV-2 is basically
from the non-human reservoirs viz. bat, camel, bovine, mice, snake etc. We aimed
to study the number of nucleotide substitutions throughout the course of evolution
in the coronaviruses. Clustal Omega multiple alignment tool was used for studying
mutations in nucleotide and amino acid sequences. The structure of spike protein
was designed using Swiss modelling and then interactions were studied by PyMOL.
On comparing the results of genome sequences in animal reservoirs, it was seen that
in the Receptor Binding Domain (RBD) of the Spike Protein of SARS-CoV-2, number
of mutations have taken place enabling the zoonotic strain to find its way to internalize
into human cells by using human Angiotensin Converting Enzyme 2 (ACE-2) as host
receptor. Open Reading frame (ORF) region of SARS-CoV-2 had shown more number of
mutation in coronavirus as compared to viral genome in bats. These mutations in
Coronavirus of bats have enabled them as a serious diseases causing pathogens to
humans.
