Team:SDU-Denmark/Tour40

Results

"I know that I am intelligent, because I know that I know nothing." – Socrates

The next few pages will guide you through the results of the characterization of our submitted parts. On this page, you will find short descriptions of our results, leading you to the final result. We hope you will dig deeper into the results of our systems. After the need to prioritize subprojects, the aim of our project was to get E. coli to express a self-designed nutritional protein, controlled by an inducible promoter. Furthermore it will express limonene synthase for the synthesis of limonene, the main part of lemon flavor.

Synthesis of self-designed protein OneProt

Pictures of worms/WB
Growth curve

Controlling the Tet promoter

Figure 2: Plate containing 200 ng/mL doxycycline plated with E. coli WT and E. coli expressing GFP controlled by a constitutive promoter, pTet-TeR(+LVA) and pTet-TetR(no LVA). Figure 1: Plate containing 0 ng/mL doxycycline plated with E. coli WT and E. coli expressing GFP controlled by a constitutive promoter, pTet-TeR(+LVA) and pTet-TetR(no LVA). In order for us to be able to control the amount of OneProt produced, we need a promoter that can be controlled. For this, we put OneProt under expressional control by pTet. Besides investigating the controllable expression, we also investigated the influence of the LVA tag on TetR. We proved that the inhibition of pTet by TetR is correlated with the concentration of inducer – increasing amounts of inducer means decreasing levels of inhibition of pTet. Comparing the expression by pTet controlled by TetR with and without LVA tag shows that there is a higher expression upon induction, using TetR with LVA than using TetR without LVA. We also show that the pTet is leaky.

Figure 3: Dose response to doxycycline.

Flavor improvement

The thought of eating E. coli does not sound that delicious – and that is why we want our OneProt to taste like lemon. Though the cloning proved unsuccessful. However, we have characterised an odor-free E. coli strain and compared it with a wild type K12 MG1655 E. coli strain. We have used Ion Mobility Spectroscopy to analyse the two strains, since we deemed it among the best methods to analyse odors. From the results it was shown that the odor-free strain does not produce indole, which is the compound responsible for the characteristic odor of E. coli.

Added parts and devices

To the great iGEM Registry of Standard Biological Parts we have added 3 basic parts, 2 regulatory devices, 1 constitutively active production device and 4 regulable production devices.