Differential specificity of SARS-CoV-2 main protease variants on peptide versus protein-based substrates

Author(s)

Rocho, Fernanda R. ; Snipas, Scott J. ; Shamim, Anwar ; Rut, Wioletta ; Drag, Marcin ; Montanari, Carlos A. ; Salvesen, Guy S.

• Document type: Journal article
• Source: FEBS Journal; v. 291, n. 1, p. 9-pg., 2023-11-03.

Abstract

The SARS-CoV-2 main protease (M-pro) holds significant importance as a biological target in combating coronaviruses due to its importance in virus replication. Considering the emergence of novel SARS-CoV-2 variants and the mutations observed in the M-pro sequence, we hypothesized that these mutations may have a potential impact on the protease's specificity. To test this, we expressed M-pro corresponding to the original strain and variants Beta1, Beta2, and Omicron and analyzed their activity on protein-based and peptide substrates. Although we observed differential activity on the protein-based substrate, there was very little difference when analyzed on the peptide substrate. We conclude that mutations on the M-pro sequence, despite having a minor effect on a peptide substrate cleavage, did not change the catalytic site environment enough to build resistance to inhibition. Therefore, we propose that inhibitors initially designed for the M-pro of the original strain will be effective in all the variants. Thus, M-pro is likely to continue to be a target of therapeutic interest as mutations in its sequence are rare and, as we show here, have a minor effect on the protease's recognition of peptide-based molecules. (AU)

• FAPESP's process: 22/01393-5 - On the development of SARS-CoV-2 3CL Mpro Coronavirus main protease inhibitors as antiviral agents
• Grantee: Carlos Alberto Montanari
• Support Opportunities: Regular Research Grants