Determination of SARS-CoV-2 Main Protease (M^pro) Activity Based on Electrooxidation of Tyrosine Residue of a Model Peptide.

Filippova, Tatiana A.; Masamrekh, Rami A.; Farafonova, Tatiana E.; Khudoklinova, Yulia Yu.; Shumyantseva, Victoria V.; Moshkovskii, Sergei A.; Kuzikov, Alexey V.

The proposed approach for determining catalytic activity of the SARS-CoV-2 main protease (Mpro) is based on registration of the peak area of electrochemical oxidation of tyrosine residue in the model peptide substrate CGGGAVLQSGY immobilized on the surface of a graphite screen-printed electrode (SPE) modified with gold nanoparticles (AuNP). The AuNP were obtained by electrosynthesis. Steady state kinetic parameters of Mpro in the reaction with the model peptide were determined: catalytic constant (kcat) was (3.1 ± 0.1) × 10−3 s−1; Michaelis constant (KM) was (358 ± 32) × 10−9 M; catalytic efficiency (kcat/KM) was 8659 s−1/M. The limit of detection (LOD) determined for Mpro using the proposed electrochemical system was 44 nM. The proposed approach is a promising tool to search for new Mpro inhibitors as drugs for treatment of coronavirus infections.

PHYSICAL & theoretical chemistry; PEPTIDES; CORONAVIRUS diseases; CORONAVIRUS disease treatment; GOLD nanoparticles

Biochemistry (00062979), 2025, Vol 90, Issue 1, p120

0006-2979

Academic Journal

10.1134/S0006297924603836