Comparison of Severe Acute Respiratory Syndrome Coronavirus 2 Spike Protein Binding to ACE2 Receptors from Human, Pets, Farm Animals, and Putative Intermediate Hosts
Xiaofeng Zhai, Jiumeng Sun, Ziqing Yan, Jie Zhang, Jin Zhao, Zongzheng Zhao, Qi Gao, Wan-Ting He, Michael Veit, Shuo Su
Abstract
SARS-CoV-2 is threatening people worldwide, and there are no drugs or vaccines available to mitigate its spread. The origin of the virus is still unclear, and whether pets and livestock can be infected and transmit SARS-CoV-2 are important and unknown scientific questions. Effective binding to the host receptor ACE2 is the first prerequisite for infection of cells and determines the host range. Our analysis provides a framework for the prediction of potential hosts of SARS-CoV-2. We found that ACE2 from species known to support SARS-CoV-2 infection tolerate many amino acid changes, indicating that the species barrier might be low. Exceptions are dogs and especially pigs, which revealed relatively low ACE2 expression levels in the respiratory tract. Monitoring of animals is necessary to prevent the generation of a new coronavirus reservoir. Finally, our analysis also showed that SARS-CoV-2 may not be specifically adapted to any of its putative intermediate hosts.