Abstract
The structural proteins, spike (S), nucleocapsid (N), membrane (M), and
envelope (E), of severe acute respiratory syndrome (SARS-CoV-2) play a
critical role from attachment to replication and virulency. Recently a
bulk of genomes have been sequenced from different geographical regions
with significant number of variations. Therefore, the current study was
aimed to find variations in the structural proteins. This is the first
comprehensive study in which we screened 2,95,000 complete genomes in
global initiative on sharing all influenza data (GISAID), submitted from
December 2019 to December 2020. We detected 4725 non-synonymous
mutations in S, 627 in M, 259 in E, and 1631 mutations in N protein,
among which the most frequently occurring mutations in S protein are
D614G (n=2,66,513), A222V (n=59,697), L18F (n=28,015) and that of M
protein are; T175M (n=1286), D3G (n=968), L17I (n=621), A2V (n=463), and
A2S (n=460). The most commonly circulating variants in E includes, S68F
(n=419), P71S (n=264), and L73F (n=218). Similarly, the N protein also
harbored the most common variants which include; R203K (n=82,570), G204R
(n=81,858), and A220V (n=39,729). The frequency of N501Y (n=4362) in S
is determining a tight interaction of CoV-2 RBD with ACE2. These wide
range of mutations in structural proteins may not only affect the
therapeutic efforts but also the vaccines efficacy and diagnostics
specificity. We suggest that geographically strain specific variations
should be investigated for effective drugs, vaccine, and the antibodies
combinations. Alternatively, immune boosting compounds might be very
useful for successful eradication of CoV-2 infections.