Revision as of 05:27, 22 September 2015

OmpA-scFv(Anti-EGFR)

Introduction:

Fig.1 OmpA-N-scFv(anti-EGFR)

To display the antibody outside the E. coli, we used Lipoprotein-Outer membrane protein A (Lpp-OmpA). According to the paper reference ^[1], We chose the first 9 amino acid of Lpp, and the 46~159 amino acid of OmpA.
In order to change the scFv parts easily, we added a NcoI restriction site between OmpA and scFv so that we can change various scFv DNA sequence by using the NcoI restriction enzyme.
Fig.2 showed how we combine Lpp-OmpA-N and scFv together, first we use restriction enzyme NcoI to digest the upstream and downstream parts. After ligate two digest product, there are no mixed site in Lpp-OmpA-N-scFv.

Fig.2 The combination of OmpA-N-scFv

Fig.3 OmpA-N-scFv

Experiment:

Fig.4 The PCR result of the Lpp-OmpA-N+scFv. The DNA sequence length is around 1000~1200 bp, so the PCR products should appear at 1200~1400 bp.

After receiving the DNA sequences from the gene synthesis company, we recombined each OmpA-N-scFv gene to PSB1C3 backbones and conducted a PCR experiment to check the size of each OmpA-N-scFv. The DNA sequence length of the OmpA-N-scFv are around 1000~1200 bp. In this PCR experiment, the OmpA-N-scFv products size should be near at 1200~1400 bp. The Fig.4 showed the correct size of the scFv, and proved that we successful ligated the scFv sequence onto an ideal backbone.

Fig.5 OmpA-N-scFv(Anti-EGFR)

Sequence and Features