Overall project

The goal of the iGEM Team Braunschweig is to create a synergetic system similar to a natural symbiosis. During the course of our project we want to clone three individual mutant strains of the bacterium Escherichia coli that can only survive as a community.

Quorum Sensing

The selective survivability of the bacteria is realised via a Quorum Sensing dependend antibiotic resistance. Quorum Sensing is a form of chemical communication allowing bacteria to measure the concentration of similar cells in their vicinity. In our project three different Quorum Sensing systems are used: the Las and Rhl system from Pseudomonas aeruginosa and the Lux system from Vibrio fischeri. Each of our three strains maintains a constitutive expression of a Quorum Sensing system specific inactive transcription activator which can initiate the transcription of the needed antibiotic resistance once complemented. To complement the functionality of the activator an autoinducer is needed. These are homoserinelactone derivates synthesised by the constitutively expressed autoinducer synthase and subsequently secreted into the medium. The main idea is that each strain cannot produce the autoinducer activating its own Quorum Sensing system. Hence the three strains have to complement each other in order to survive.

Schematic illustration of the E.T.eamwork system

Project Details

Part 2

The Experiments

Part 3