Throughout our project, we have successfully transformed E. coli competent cells and validated the expression of the Gb3 synthase mRNA from the arabinose inducible part using RT-PCR and PCR amplification. Figure 1 shows colony growth of appropriate selective media. Bands corresponding to amplified Gb3 synthase products resulting from the three different sets of primers used are shown in Figure 2 .
Additionally, we have validated the production of Indole in E. coli cells transformed with Part:BBa_K1867024 using the Kovac’s reagent tube test. Figure 3 represents the change in color as an indication of indole production from transformed cells.
Finally, we have successfully designed and 3D printed a prototype of our device that will eventually, once fully functional, will allow for the detection Shiga toxin contaminations of food samples in a period of time not exceeding 45 mins with no lab setup required and in a user friendly, mostly hands-off manner. Figures displaying our design and showing the prototyped device in 3D can be found in the Design Page.
All of our results are reproducible using the protocols we followed, which are available in our Experiments Page.
As any project, ours also suffered from several failures:
- We failed to perform experiments detecting successful synthesis of Gb3 in cells that expressed Gb3 synthase.
- We also failed to run experiments to isolate and purify the His-tagged Subunit B of the Shiga-like toxin encoded by one of our submitted parts due to delays in procurement and delivery of required equipment and reagents.
- We failed to transform and validate expression of Gb3 synthase from our part encoding the Gb3S under control of a strong constitutive promoter. We suspect that the promoter strength had led to an excessive expression of Gb3S that turned out to be detrimental to our cells.
- We failed to drive our device to its complete functionality and as it stands now, it remains at a prototype stage.
We aim to address all of the failures above in later years, and improve our experimental protocols to validate all of our submitted parts and drive this project to completion. We also aim to reach a fully functional device, and we hope to get the chance to show our functional device in later years.