Furin cleavage sites naturally occur in coronaviruses

Furin cleavage sites naturally occur in coronaviruses: The spike protein is a focused target of COVID-19, a pandemic caused by SARS-CoV-2. A 12-nt insertion at S1/S2 in the spike coding sequence yields a furin cleavage site, which raised controversy views on origin of the virus. Here we analyzed the phylogenetic ...