Part:BBa_K5302013

This work is derived from pBBR1MCS-mCherry and pUC19-Lpp-OmpA, and it has undergone codon optimization. This composite part combines LppOmpA( It’s a combination of LppSP-9aa and OmpA46-159aa, which is supposed to be a better surface transmitting system.) and mCherry(26.7kda), and we succeeded in transferring this plasmid into Escherichia coli Nissle 1917 and let it express mCherry as a fluorescence labeling.The plasmid uses lac promotor and has kanamycin resistence. Lpp-OmpA is a fusion protein system used for bacterial surface display in Escherichia coli (Escherichia coli). This system utilizes the signal peptide of Lpp and the first nine amino acids of its mature sequence, and the five β -folded transmembrane domains of OmpA, to display the foreign protein on the bacterial outer membrane. In E. coli, the Lpp-OmpA fusion protein can serve as an efficient targeting vector to locate a variety of prokaryotic and eukaryotic soluble proteins to the cell surface, providing a system for a variety of possible biotechnological applications. The design of the Lpp-OmpA vector was based on the outer membrane structure of E. coli. In this vector, the Lpp domain is responsible for anchoring the fusion protein to the outer membrane, while the OmpA domain is responsible for the surface expression of the foreign protein.

Figure 1. structure of OmpA, from genebank

Figure 2. Colony PCR results of pBBR-LppOmpA-mCherry