Team:SHSBNU China/Demonstrate
Demonstrate
The purpose of our design (PORBE) is to make improvement on gut inflammation sensing system in 2017. Our design will encapsulate gut inflammation sensing E.coli cells and apply the capsule orally to the patients. The E. coli strands would be able to record the information of a patient’s gut on its DNA via the BBa_K3156888（SCRIBE）gene editing system. Different from our project in 2017, which can only give a rough estimation based on the color of a patient’s feces, our new project can record the amount of thiosulfate that the capsule encountered in the patent’s gut. Therefore, After the capsule exited the patient’s body, it could be retrieved and sent to medical institutions where quantitative analyses could be performed, and specialists would be able to estimate the level of the patient’s gut inflammation based on the results.
To achieve that design, we made several improvements. The thiosulfate sensing mechanism that we used in our 2017 project had high leakages. Therefore, we built RBS library and improved the thiosulfate sensing mechanism as our PORBE sensor. Then we applied a DNA editing system, known as BBa_K3156888（SCRIBE）, in cooperation with our improved thiosulfate sensing system to record the thiosulfate level around the capsule while it is in the patient’s gut. Because the recording happens directly on the DNA, our project would support quantitative analysis. Finally, we use gfp gene as the eventual reporter. The measurement of fluorescence intensity and proportion of bacteria that has its gfp repaired would indicate the level of gut inflammation.
The test and combination of Biosensor and DNA repairing system
Although SCRIBE was not an efficient system in our previous experimental tests, we still associated it with biosensor to test whether enteritis chemical micro molecules can trigger changes of DNA sequence information, and changes can be quantitatively observed.
The assembly of our capsule is from a bottom-top order. We firstly use 3D-printing technology to create the shell of our capsule. The chamber below is used to store culture medium. The semi-permeable window is the pathway that allowed chemical molecules to enter. The bacteria are placed on the top of the chamber and the seal. After the capsule entering internal environment, the magnet above will be attracted. And the top seal will prevent the medium from spillage.
So, we will first inject medium into the chamber then seal the chamber before we place the bacteria. When we use a homopolar magnet to generate repulsion between two magnets. Then the magnet will propel the push rod. Therefore，the bacteria will enter the chamber.
We used magneto to remote control the position of capsule