Bioinformatics analysis and comparison of the S protein of canine coronavirus and feline coronavirus

The Coronavirus S protein induces neutralizing antibodies, specific receptor binding, and membrane fusion between the virus and host cells. These changes are crucial to understanding the mechanism, genetic correlates, and prophylactic treatment of viral infection. In this study, the spike (S) protein structure and phylogenetic association of CCoV and FcoV were analyzed using bioinformatics. The results showed that the S proteins of CCoV and FCoV contained transmembrane regions and signal peptides. The S proteins of these coronaviruses were soluble. The S proteins of these strains also contained two functional domains and two motifs, i.e., corona_S1 and corona_S2. Phylogenetic analysis showed that CCoV-I and FCoV-I were included in the same clade, while CCoV-IIb, FCoV-II, and TGEV formed another clade. Our findings can provide a theoretical basis for further understanding the function of coronavirus S proteins and the design of antiviral drugs and vaccines.