Fusion Protein Placement for Mammalian Cell Expression

Proteos is an industry leader in the production of high-quality recombinant proteins for drug discovery research and can work with you to design the optimal mammalian cell expression construct.

When designing mammalian cell expression constructs, addition of a fusion partner such as Fc or human serum albumin (HSA) may be advantageous for increasing the expression or solubility of the target protein. However, the design and placement of a fusion protein partner relative to the protein of interest must be critically considered and empirically tested since it can significantly affect protein expression and function.

Fusion proteins can be placed at the N- or C-terminus of the target protein and can be paired with small affinity tags to facilitate purification.  Protease cleavage sites can also be included to allow enzymatic removal of the fusion partner during purification. With large fusion partners such as Fc (26 kDa) and HSA (66 kDa), inclusion of flexible amino acid linkers between the proteins may be necessary to preserve the proper conformation and functionality of the target protein.

Expression testing of multiple constructs is key to identifying the optimal construct for protein production and can easily be included in Proteos’ milestone-driven project design, prior to pilot scale yield determination and preparative scale production.

The final blog post in this series will discuss removal of the fusion protein in more detail.  But, if you don’t want to wait, contact us now for more information. We will guide you through the process and design a custom quotation that fits your specific project needs.