Researchers identified a structural loop in the SARS-CoV-2 spike protein, the area of the coronavirus that facilitates entry into cells, and a sequence of four amino acids in the loop that are different from other known human coronaviruses in this viral lineage. SARS-CoV-2 has some shared properties with the 2003 virus responsible for the SARS outbreak. The loop appears to be important to both the transmission and stability of the virus. The study also found that in addition to humans and primates, cats, ferrets, and minks are also susceptible to COVID-19 infection.
