Basic Part
This year, our team uses a new kind of cell-surface display system-Ice Nucleation Protein (INP) as a new kind of basic part (BBa_K2552003). The full-length INPs (called INP in our project) are comprised of three distinct structural domains distinguished as the N-terminal domain (15%), the C-terminal domain (4%) and the central repeating domain (81%). In our team, we use the N-terminal domain of full-length INP as an anchoring motif to display T antibody.
Another kind of wildly used cell-surface display system is the OmpA system. Considering more and more teams are focusing on cancer targeting, we added a 15-amino acids oligo peptide to the C-terminal of OmpA to give it the ability to target cancer. The oligo peptide has the ability to bind to Thomsen–Friedenreich antigen (T antigen) that exist on some kinds of cancer cells (like colorectal cancer) by a mechanism similar to antigen-antibody binding reaction.
We also add a basic part (BBa_K2552007) that uses the Pyear promoter to regulate the expression of the azurin protein. With the lysis of our strain, the azurin protein is released to kill the CRC cells at the lesion position.
Part Collection
In this year’s project, one of our most important parts is the adhesion between our engineered E.coli and the cancerous cells. In order to equip our bacteria with this function, we developed several biobricks for attachment through antigen-peptide binding. The main information and corresponding links are listed below.
Table 1. Part Collections
| Part | Registry Name | Function |
|---|---|---|
| Antibody T-1 | BBa_K2552000 | binding to T antigen on cancer cells |
| Antibody T-2 | BBa_K2552001 | binding to T antigen on cancer cells |
| Antibody T-3 | BBa_K2552002 | binding to T antigen on cancer cells |
| INP-Antibody T-1 | BBa_K2552004 | displayed on E.coli outer membrane and binding to T antigen on cancer cells |
| Ompa-Antibody T-1 | BBa_K2552005 | displayed on E.coli outer membrane and binding to T antigen on cancer cells |
| Ompa-Antibody T-2 | BBa_K2552006 | displayed on E.coli outer membrane and binding to T antigen on cancer cells |
