Team:Leiden/Collaborations

Collaborations

During the project we collaborated with many iGEM teams, institutions and organizations, as visualised on the above shown map.

The iGEM team Copenhagen performed a series of experiments in a Martian chamber to assess survival under Martian conditions. This Martian chamber made it possible to test the survival of wildtype bacteria in different conditions similar to the environment on Mars, for example radiation, low pressure and high levels of CO2. For our project, it was very interesting to know whether our E. coli bacteria would survive on the surface on Mars in the worst case scenario they would escape their contained environment of the bioreactor. [LINK] The Copenhagen team therefore tested for us what the effect of the low pressure atmosphere is on bacteria. The team exposed E. coli-strain DH5α, which we used to transfer our detoxification system to, to the pressure levels present on Mars, which is between 0.5 ad 0.7 kPa. Then, they measured optical density (OD) to study how many of the bacteria were still alive. Their results, though very small in sample size, suggest that E. coli has very low, if any survival at all. Thereby, the rod-shaped bacteria seemed to show a slightly shorter and thinner, more rod-shaped phenotype under a reduced pressure of 0.5 kPa in comparison to these bacteria grown under normal air pressure (1 kPa). This shows us again, just as in the Random Positioning Machine [LINK], that Martian conditions certainly will have an effect on our bacteria on Mars.

Figure 1: The martian chamber

Figure 2: Low pressure chambers

Still, there was one condition their Martian chamber wasn't able to test that we could provide the Copenhagen team with: the reduced gravity on Mars, which is only 38% of the Earth's gravity. By using the Random Positioning Machine, which rotates the samples inside in a pre-programmed way such that it only experiences a part of the Earth's gravity level (normally 1g), which you can vary between 0g and 0.9g. We were able to show that Bacillus subtilus 168 and Synechococcus elongatus PCC 7942 grow to higher densities in simulated Martian gravity (0.38g) in comparison to bacteria under the Earth's gravity on the same time interval. This experiment showed thus that their bacteria would survive the gravity levels on Mars and might even experience growth-benefits from it, which is highly important for their bioplastic producing co-culture between these organisms to work.

Figure 3: Bacterial cultures at different pressures