Fig. 2.

SARS-CoV 3CLpro cleavage sites and the canonical recognition sequence. The 11 recognition sequences of SARS-CoV 3CLpro from the P6 to P5′ positions are shown with their respective locations between the respective nsp's. The relative k_cat/K_m values for the series of 11-mer peptide substrates are also given (Fan et al., 2005). A canonical recognition sequence is proposed based on the relative k_cat/K_m values for SARS-CoV 3CLpro, and the recognition sites of a series of other coronavirus 3C proteases (Kiemer et al., 2004, Thiel et al., 2003).