NMR Observation of Sulfhydryl Signals in SARS-CoV-2 Main Protease Aids Structural Studies
The 68-kDa homodimeric 3C-like protease of SARS-CoV-2, Mpro (3CLpro/Nsp5), is a key antiviral drug target. NMR spectroscopy of this large system proved challenging and resonance assignments have remained incomplete. Here we present the near-complete (>97 %) backbone assignments of a C145A variant of Mpro (MproC145A) both with, and without, the N-terminal auto-cleavage substrate sequence, in its na