Template:Team:Groningen/CONTENT/PROJECT/Results
Overview of achievements
- Developed several genetic constructs which resulted in distinct biofilm phenotypes
- Created salt inducible promoter to control several biofilm genes
- Validated both the salt inducible PproH promoter (BBa_K1597000) and tasA (BBa_K1597002)
- A new shuttle vector (BBa_K1597001) was created for integration in the thrC locus in B. subtilis
- Used combinations of these constructs to create a biofilm which is ion selective
- Demonstrated ion-selectivity of B. subtilis biofilm with our prototype in the real-world
- y-PGA was modeled as a Cation Exchange membrane using Molecular Dynamics
- Created future scenarios about our project and the use of GMOs.
- A card game was developed to teach about synthetic biology in a fun way
Phenotypical differences after biobrick introduction in B. subtilis
The introduction of the developed biobricks in B. subtilis, changes the behaviour of the bacterium. This resulted in different phenotypes after growing for 24 hours, where we can conclude that the developed biobricks have an impact on B. subtilis.
Created salt inducible promoter to control several biofilm genes
To increase the the robustness and the ion selectivity of the biofilm, several biobricks were developed, where an overproduction of biofilm involved genes were introduced to B. subtilis . Several of these genes were controlled under the developed salt inducible promoter. Introduction of these biobrick led to different phenotypes.
To validate that our biobricks function as expected, a tasA overproducing strain was made under the control of the salt inducible PproH promoter. The use for salt inducible PproH promoter showed an increasement of TasA after induction with NaCl in two different experiments. Induction of salt also showed a different phenotype.
A new shuttle vector
An extra integration locus is welcome when making a multiple mutant. Therefore a shuttle vector was designed and created (BBa_K1597001). The backbone is capable of reproducing in E. coli and integrating in the thrC locus from B. subtilis.
Ion selectivity in the lab
To test the ion selectivity, the volts generated by the membrane was measured and the ion-selectivity can be calculated using the Nernst equation. Calculation showed that a theoretical maximum energy potential 86 mV is.
Demonstration of working prototype
The ultimate test was if our prototype could work with actual seawater and water from the lake. This test was performed and the results are significant. It was expected that the ion-selectivity would be lower hence real sea and lake water was used for this experiment. However the obtained yield was higher than previous measurements. This indicates that our prototype can function in the real world.
y-PGA
To show how the ion-selectivity of the biofilm could be enhanced, a molecular dynamic model was used. The molecular dynamics showed that y-PGA could function as a cation exchange membrane. This will contribute to a negative charge of the biofilm, where an overexpression of y-PGA in B. subtilis could make the biofilm ion-selective for sodium ions. This could increase the total amount of energy generated.
Future scenarios for Blue Bio Energy
Before applying a new technology in society, it is vital that research has been done into the reaction of the public. Therefore 3 future scenarios were created, with none Blue Bio Energy, Blue Bio Energy and too much Blue Bio Energy. This gave perspective about which underlying principles motivates stakeholders when forming an opinion on a new technology.
Card game, the fun way of learning synthetic biology
The synthetic biology cardgame was designed and created with the aim of teaching about synbio and iGEM in a playful way. More than hundred children have played it and all the feedback was used to create a game that is fun and educational. The teachers have been supportive as well and want to use the card game to explain synthetic biology at school.