SARS-CoV-2 Main Protease Substrate

SARS-CoV-2 main protease Mpro (3CLpro) represents a major target in drug development against COVID-19. BIOSYNTAN offers a fluorogenic FRET substrate for activity determination and inhibitor screening of Mpro protease :

SARS CoV substrate

The enzymatic assay was developed by the Hilgenfeld group [1,2]. It takes advantage of a convenient read out of the fluorescent cleavage product (excitation at 340 nm / emission at 490 nm).


Our recently developed rhodamine110 Mpro substrate proved to be even superior in fluorescent protease assays. The red-shifted excitation (492nm) and emission (529nm) shows better signal-to-noise ratio and produces less interference with potential inhibitors in screening assays. This leads to a higher sensitivity compared to the Dabcyl/Edans substrate. In consequence, lower substrate amounts are necessary for successful assays.


[1]   L. Zhang, R. Hilgenfeld et al., J. Med. Chem., 2020, 63, 4562-4578.
[2]   L. Zhang, R. Hilgenfeld et al., Chem. & Biol., 2008, 15, 597-606.