Predicted structural mimicry of spike receptor-binding motifs from highly pathogenic human coronaviruses

Beaudoin, Christopher A; Jamasb, Arian R; Alsulami, Ali F; Copoiu, Liviu; van Tonder, Andries J; Hala, Sharif; Bannerman, Bridget P; Thomas, Sherine E; Vedithi, Sundeep Chaitanya; Torres, Pedro H M; Blundell, Tom L

Viruses often encode proteins that mimic host proteins in order to facilitate infection. Little work has been done to understand the potential mimicry of the SARS-CoV-2, SARS-CoV, and MERS-CoV spike proteins, particularly the receptor-binding motifs, which could be important in determining tropism of the virus. Here, we use structural bioinformatics software to characterize potential mimicry of the three coronavirus spike protein receptor-binding motifs. We utilize sequence-independent alignment tools to compare structurally known or predicted three-dimensional protein models with the receptor-binding motifs and verify potential mimicry with protein docking simulations. Both human and non-human proteins were found to be similar to all three receptor-binding motifs. Similarity to human proteins may reveal which pathways the spike protein is co-opting, while analogous non-human proteins may indicate shared host interaction partners and overlapping antibody cross-reactivity. These findings can help guide experimental efforts to further understand potential interactions between human and coronavirus proteins. Highlights Potential coronavirus spike protein mimicry revealed by structural comparison Human and non-human protein potential interactions with virus identified Predicted structural mimicry corroborated by protein-protein docking Epitope-based alignments may help guide vaccine efforts Graphical abstract