Through this year our iGEM team continued the work of previous teams, such as the Uppsala iGEM team 2024 and mainly team FAFU-CHINA 2019.
We took inspiration from these projects and built on their foundations by introducing our own improvements.
One of our main contributions was the incorporation of introns into the sequences of FLO1 protein developed by FAFU-CHINA 2019,
with the goal of improving flocculation efficiency in C. reinhardtii.
In addition, we explored the potential of the Z17–Z18 protein complex as an alternative system that could be tested not only
in C. reinhardtii but also in E. coli, broadening the flexibility and applicability of this approach.
To create a proof of concept, we attached Z17 and Z18 to an autotransporter EhaA that we used in E. coli.
However, this mechanism does not work in C. reinhardtii, so we used the native protein GP1.
By attaching Z17 or Z18 to GP1, these proteins may be displayed on the surface. To verify expression, a green fluorescent
protein was also attached to the construct.
This cassette holds a lot of potential as previous literature has shown that proteins attached to GP1 are displayed on the cell surface.
Although we did not get to test it in C. reinhardtii, it could be used by other iGEM teams who are looking into flocculation.
Furthermore, this cassette may be redesigned with another protein, replacing Z17 and Z18, enhancing the versatility.
Beyond experimental design, we also focused on improving reproducibility and measurement accuracy in the lab.
To address challenges with variability in optical density (OD) readings, we developed a protocol for consistent quantification of
cells using a cell counter. This provides an alternative to OD-based measurements and can help future teams compare data across
different experimental conditions more effectively. We needed a way to measure flocculation in algae which gave rise to the cell
counter method. There are not many flocculation assays available today, and it will be of use to future iGEM teams who are studying
flocculation. Together, these contributions aim to strengthen the toolbox for algal synthetic biology and offer practical methods and
resources for upcoming iGEM teams. Check out the measurements page here