Microorganisms are of critical importance in our ecosystems since they play a roll of natural decomposer. If it were not for microbes, the earth might become awash with fallen leaves, dead bodies and other debris. Bioremediation is an idea of utilizing this bacterial property to fight pollution. Synthetic biology has made it possible to create microorganisms that are specialized for this task, thereby allowing implementation of high efficiencies.
In the past iGEM competitions, quite a few teams have developed devices for bioremediation. Most of the projects focused on the method to deal with substrates (collection, reduction, etc...) and the efficiency of the system was not so emphasized. At the actual polluted site, however, microorganisms are not always able to interact with substrates in an ideal condition. If we can make microorganisms to interact with substrates effectively regardless of the environment, the efficiency of bioremediation will improve dramatically.
To solve this problem, we designed a "Self-Mustering with Aspartate-Responsive Taxis (SMART) System." The basic strategy of the SMART system is quite simple. "The higher the concentration of microorganisms around the substrate, the better the efficiency of bioremediation." Without a device like SMART, we predict that many projects require an enormous amount of time to complete the task using realistic concentrations of microorganisms.
Take a look at the two movies below. Movie1 shows the way the microorganisms decompose the localized substrate with cell diffusion only, and Movie2, with SMART system. You will see microorganisms decompose the substrate much more rapidly with SMART system. From this simulation, we predict that SMART system greatly accelerates the decomposition of the substrate.

Movie 1. Bioremediation with cell diffusion only: Left side indicates Asp diffusion and right side indicates E. coli distribution.
  • If you cannot load the file, click [here].

Movie 2. Bioremediation with SMART system
  • If you cannot load the file, click [here].

SMART system is designed in such a way that it is applicable to allow bioremediation of various substrates with good efficiency.
In the System page, we will introduce details of our SMART system.