Table 1 Cleavage site sequences of chikungunya virus nsP2 protease

Three synthetic fluorescent substrates designated as AGA, AGC and AGG as underlined were synthesized corresponding to the cleavage site sequence of chikungunya virus nsP2 protease (nsP1/2, nsP2/3 and nsP3/4), respectively. 2-(N-methylamino)benzoyl (Nma) fluorophore group attached at the amino terminus and a 2,4-dinitrophenyl (Dnp) group attached to the carboxyl terminus of Lysine (K) residue.

Cleavage site (P4–P5′)Recognition siteDesignated name
nsP1/2Nma-RAGA/GIIETk(Dnp)-OHAGA
nsP2/3Nma-RAGC/APSYRk(Dnp)-OHAGC
nsP3/4Nma-RAGG/YIFSSk(Dnp)-OHAGG