Figure Legends
FIGURE 1 : Geographic mapping of SARS-CoV-2 outbreak and its
timeline of infection. A) SARS-CoV-2 variants of concern (VOC) as
classified by the World Health Organization (WHO) and their first
reported case represented on a world map. B) Global timeline of
SARS-CoV-2 cases in thousands wherein weekly cases of SARS-CoV-2 VOC as
obtained from the GISAID database from December 2019 to February 2022
FIGURE 2 : Schematic and structural annotation of SARS-CoV-2
spike glycoprotein variants. A) Mutations in each of the VOC- Alpha,
Beta, Gamma, Delta and Omicron mapped on the SARS-CoV-2 spike gene.
Substitutions are represented with yellow circles, deletions with red
triangles and insertions with green triangles. Common mutations to
multiple VOC have been connected through a standard line at that residue
position. NTD: N-terminal domain, RBD: receptor binding domain, FP:
fusion peptide, HR1: heptad repeat sequence 1, HR2: heptad repeat
sequence 2, TMD: transmembrane domain. B) Mutations involved in each of
the VOC of SARS-CoV-2 mapped on spike monomer. Mutated residues are
depicted in red spherical representation and spike monomer shown in
cartoon representation (PDB: 7df4). RBD in open conformation is depicted
in orange and NTD in green. Epitopes that could not be marked in the PDB
structure are marked with a dashed line and red spot at the location of
the neighboring residues. V1176F mutation in the Gamma variant has not
been shown since it belongs to the stalk region of spike which was was
not available in the spike PDB structure of 7df4.
FIGURE 3 : Heat map of epitope residues of monoclonal
antibodies. The epitope residues of the analysed mAbs are plotted as a
heat map wherein the highest intensity colour is denoting the most
frequent epitope site followed by the decreasing the colour gradient
which depicts the less frequent epitope sites.
FIGURE 4 : Epitope mapping of monoclonal antibodies
targeting SARS-CoV-2 spike. Mapping of epitopes of 74 experimentally
validated mAbs against SARS-CoV-2 variants. The mutated epitope sites
with respect to the Alpha, Beta, Gamma, Delta and Omicron variants are
annotated as red, whereas the non-mutated sites are shown in green. The
antibodies selected for the analysis are depicted on the y axis. The
mutated epitope regions within the spike N-terminal domain are
subdivided into N1, N2, N3 and N4 and the receptor-binding domain (RBD)
is sub annotated as receptor binding motif (RBM) within RBD.
FIGURE 5 : Frequency of mutated epitopes and the amino acid
changes at the epitope sites. A). The frequency of mutated epitopes
among the 74 mAbs was analyzed based on the region of occurrence and is
shown as colormap with different frequencies. B) The percentage of amino
acid variations at the epitope site among all reported SARS-CoV-2
variants were mapped and shown as a bar graph with different colors
depicting each amino acid change in a series. In addition, the mutated
epitope regions within the spike protein are denoted structurally and
are shown as residues labeled in red. In contrast, the complete epitope
recognition sites are marked as yellow. Some of the epitope recognition
sites (Amino acid residues- 12,
13,14,15,74,75,76,248,249,250,251,252,253,254) which are non-mutated
couldn’t be marked as yellow as these where not depicted in the
structure.