Team:OUC-China/Futurework/Fa

From 2011.igem.org

        In order to achieve non-interfering contacts among five different types of bacteria, we totally selected three series of QS signal systems and standardized its 8 biobricks and one leucine-complementary gene through our teamwork.
        Based on related papers, we chose and standardized some DNA parts that had never been used in iGEM before. We extracted raiI, raiR and their promoters of raiI quorum sensing signal system from Rhizobium etli CFN42, and saiI, saiR and their promoters of sinI QS system from Sinorhizobium meliloti 1021. We also standardized rhiI and rhiR and their promoters of Rhi QS system. Leucine-fixing part came from common bacteria: BL21, which can be applied to fix incomplete metabolic pathway of leucine-deficient bacteria.
        We focus on providing new communication language for bacteria, and our work finally paid off. We believe that these three sets of signal communication systems among different species of rhizobium will greatly expand the potential ways of communication among bacteria.
        Besides, the present work of our project enables several kinds of bacteria to form an inter-supportive and/or inter-inhibitive net system without interference, sequentially serves as an efficient basic model for multi-bacterial symbiosis and cooperation. Furthermore, a multi-bacteria system of high safety was raised based on this “single-circle & reverse-feedback” model.

         Therefore, we believe that this stable and safe mutualistic symbiosis model has the following meanings:
NO.1 Metabolism Separation and Combination
        Someday in the future, we might divide a single metabolic pathway into different bacteria for research based on this model, setting up a dynamically balance with cell growth promoting and restraining to stably maintain a functionally continuous reaction system, like running a “biochemistry pathway relay” in fermenter.
No.2 Stable Multi-bacteria Complex Fermentation
        Someday in the future we may fulfill artificial “Domino” fermentation reaction to promote more stable complex fermentation.
No.3 Bricks of biological interferon system model
        Contributions to ecology research: someday we may also use these bricks to imitate the complex relations among ecosystem and community evolution.
No.4 Multiple Engineering Bacteria’s Cooperation on Tasks
        One day in the future, we may use our model to make different “E.coli doctors” cooperate to execute their treatment. Also we may build a robust E.coli factory, in which different engineering E.coli could conduct teamwork of creative work.
No.5 New approach for Safety on Synthetic Biology
        As we mentioned before, the “single-cycle & reverse-feedback” model offered a multi-bacteria system of high safety. Absence of any part in this system will cause others’ death. Meanwhile, restrain among different strains can avoid the model to become eruptible but stable.