Difference between revisions of "Part:BBa K5302037"

Latest revision as of 02:31, 2 October 2024

pBBR-OmpA-l2VGB

This work is derived from pBBR-OmpA-VEGFR1D2 and pUC19-VGB, and it has undergone codon optimization. This composite part combines OmpA(21.4kda) and VEGFR1D2(approximately 12kda), and it adds a fragment as a mask. We succeeded in transferring this plasmid into Escherichia coli Nissle 1917 and let it express VEGFR1D2. The plasmid uses lac promotor and has kanamycin resistence.

This part is a cyclic peptide (known as VGB1) reproducing the α1 helix and its adjacent region based on the X-ray structure of VEGF-B/VEGFR1D2, he sequence of the designed 17-amino acid peptide (referred to as VGB1) was 2HN-CSWIDVYTRATCQPRPL-COOH. It exhibits high affinity for VEGFR-like receptors, allowing it to effectively compete with VEGF for binding to VEGFR. Consequently, this peptide has been utilized as a masking agent. Upon administration into the human body, it preemptively binds to VEGFR, preventing VEGF from engaging with the receptor. Given that matrix metalloproteinases (MMPs) are present at high concentrations in the tumor microenvironment (TME), they can degrade this VEGFR-masking peptide (designated as #29). This degradation allows VEGF to subsequently bind to the VEGFR-like receptors, triggering their activation. Therefore, this peptide functions as a biological switch, becoming active when exposed to the TME upon the entry of engineered chimeric nanoparticles ( Escherichia coli Nissle 1917).

Figure 1. structure of VGB

Sequence and Features