Download MendeleyProduction of authentic SARS-CoV M(pro) with enhanced activity: application as a novel tag-cleavage endopeptidase for protein overproduction
Xue, X., Yang, H., Shen, W., Zhao, Q., Li, J., Yang, K., Chen, C., Jin, Y., Bartlam, M., Rao, Z.(2007) J Mol Biol 366: 965-975
- PubMed: 17189639
- DOI: https://doi.org/10.1016/j.jmb.2006.11.073
- Primary Citation of Related Structures:
2H2Z, 2HOB - PubMed Abstract:
The viral proteases have proven to be the most selective and useful for removing the fusion tags in fusion protein expression systems. As a key enzyme in the viral life-cycle, the main protease (M(pro)) is most attractive for drug design targeting the SARS coronavirus (SARS-CoV), the etiological agent responsible for the outbreak of severe acute respiratory syndrome (SARS) in 2003. In this study, SARS-CoV M(pro) was used to specifically remove the GST tag in a new fusion protein expression system. We report a new method to produce wild-type (WT) SARS-CoV M(pro) with authentic N and C termini, and compare the activity of WT protease with those of three different types of SARS-CoV M(pro) with additional residues at the N or C terminus. Our results show that additional residues at the N terminus, but not at the C terminus, of M(pro) are detrimental to enzyme activity. To explain this, the crystal structures of WT SARS-CoV M(pro) and its complex with a Michael acceptor inhibitor were determined to 1.6 Angstroms and 1.95 Angstroms resolution respectively. These crystal structures reveal that the first residue of this protease is important for sustaining the substrate-binding pocket and inhibitor binding. This study suggests that SARS-CoV M(pro) could serve as a new tag-cleavage endopeptidase for protein overproduction, and the WT SARS-CoV M(pro) is more appropriate for mechanistic characterization and inhibitor design.
Organizational Affiliation:
Tsinghua-Nankai-IBP Joint Research Group for Structural Biology, Tsinghua University, Beijing, China.
