High-resolution structures of the SARS-CoV-2 N7-methyltransferase inform therapeutic development.

Emergence of SARS-CoV-2 coronavirus has led to millions of deaths globally. We present three high-resolution crystal structures of the SARS-CoV-2 nsp14 N7-methyltransferase core bound to S-adenosylmethionine (1.62 Å), S-adenosylhomocysteine (1.55 Å) and sinefungin (1.41 Å). We identify features of the methyltransferase core that are crucial for the development of antivirals and show SAH as the best scaffold for the design of antivirals against SARS-CoV-2 and other pathogenic coronaviruses.