Factor Xa Protease (Ile-Glu-Gly-Arg)
The Endoprotease that Creates Authentic Recombinant Proteins
Cleavage site of endoprotease Factor Xa; schematic drawing.
- Very high purity and high activity compared to other commercially available Xa enzymes
- Cleaves amino acid sequence N-Ile-Glu-Gly-Arg/-C at the carboxyl end
- For cleavage of fusion proteins
- Enables creation of N-terminal authentic recombinant proteins without additional amino acids
- Endoprotease Factor Xa is a specific serine protease with an extended substrate-binding region matching the Ile-Glu-Gly-Arg tetra peptide segment.
It can be used as a "restriction protease" to cleave recombinant fusion proteins specifically after the Arg residue at an inserted Ile-Glu-Gly-Arg-junction.
Expression of desired proteins or polypeptides as fusion proteins in prokaryotes will routinely produce high yields with minimal expense and lab time investment. The inserted Ile-Glu-Gly-Arg segment in front of the protein of interest allows you to vary the handling properties of the fusion protein (i.e. charge, solubility, toxicity, etc.) and to incorporate polypeptide segments conferring highly selective affinity for immobilized monoclonal antibodies or other suitable affinity substances to allow single-step purifications. Following purification, the fusion protein is treated with Factor Xa to release the desired protein with a precise N-terminal sequence determined by your vector construction. This strategy of recombinant protein production provides complete control over the N-terminal structure of the final product. Possible sequence heterogeneity due to variable extend of N-terminal processing at the methionyl residue arising from the translation initiation codon becomes unimportant, since the N-terminal part of the chimeric protein is removed in vitro. Factor Xa-cleavable fusion proteins are particular useful to prepare large amounts of authentic protein for structural work for any other application requiring substantial amounts of high-quality recombinant protein products.