3.3.2 ǀ Subcellular localization, structure, function and various properties of cpOAS1 protein
cpOAS1 protein is possibly multi-located but dominates in the cytoplasm and is a soluble protein (FIGURE 4 and Table 3) based on the result of PSORT II and DeepLoc-1.0 servers. Based on the signal peptide prediction using SignalP 5.0 server and Signal-3L 3.0 engine, there were no signal peptide and cleavage sites in the cpOAS1 protein (FIGURE 5SA). Transmembrane of TMHMM results showed that there is no predicted transmembrane helix in the sequence of cpOAS1 (FIGURE 5SB). Prediction of the secondary structure of cpOAS1 protein by the SOPMA revealed that the alpha helix (43.92%) is dominated followed by the random coil (39.86%), extended strand (13.85%) and beta-turn (2.36%) and percentage of other structures like Pi helix, Beta Bridge, Beta region, ambiguous states, etc. were zero (FIGURE 6S). Based on NetSurfP, it was found that the cpOAS1 protein has a combination of buried and exposed amino acid residues (FIGURE 5). The relative surface accessibility (RSA) value was ranged from 0.004 to 0.840 and absolute surface accessibility (ASA) was 0.672 to 151.586. Maximum disorders residues were present at the C-terminal end (FIGURE 5). Rossmann fold sequence domains and their specificity for the cofactors FAD, NAD or NADP were not found in the cpOAS1 protein (FIGURE7S). Various sequences, which show anti-oxidative properties, were found in the cpOAS1 (Table 4).

3.3.3 ǀ Immunological features of cpOAS1

B cell epitope prediction (Bepipred Linear Epitope Prediction 2.0) using IEDB analysis indicated that there are 14 potential immunogenic sites in the cpOAS1 which can act as antigen while, with a 50% threshold, seven sites act for T cell epitope (immunogenicity prediction) given in Table 5 and Figure 8S. The residues with scores above the threshold (0.5) are predicted to be part of an epitope and colored in yellow on the graph (where Y-axes depict residue scores and X-axes residue positions in the sequence).