Improved Project
Our project consisted of 6 metal inducing devices, one of which was of mercury.
While constructing that, our team also planned to work on already existed
mercury device; BBa_ K3155002 built in 2014 by the iGEM team UFAM, Brazil.
Details:
Distribution Kit 2017
Hg Device: 2075bps
Plasmid: pSBIC3
Kit Plate # 05
Well # 21N
Replicating their project helped us know the substantial difference in both of our data. Considering the difference,
we repeated our experiment multiple times and got similar results. Here’s how we collected the data and compared our results.
TRANSFORMATION
We started off by transforming their device into DH 5 alpha cells. Transformation went well and we got a good number of colonies.
MINIPREP & PCR
After transforming the cells we carried out miniprep. The miniprep was further PCRed in order to confirm the presence of their device in our bug. The pictures below show the transformed colonies and positive PCR bands.
TESTING
We have tested Team UFAM’s mercury device with different ppm i.e from 0.01ppm to 50ppm. After performing the experiment several times, it was confirmed that concentration of mercury higher than 1pmm is toxic for bacteria to grow.
OD MEASUREMENT
Below graph shows growth values of our nine samples with a negative control.
COMPARATIVE ANALYSIS
We tested this biosensor with same concentrations as the iGEM UFAM team. To our surprise, DH5 alpha didn’t show any growth in the broths having mercury level higher than 1ppm.
Graphs showing comparative results of our team (to the right) and iGEM UFAM team (to the left). The difference is vivid and it’s clear that the mercury device couldn’t give us the same results.
Another one of the heavy metals we are working on is Cadmium. In 2015, the iGEM SCUT team developed a Cadmium sensitive transcriptional factor - BBa_K1724002 for the pCadA promoter by mutating the MerR transcriptional factor. However, they were unable to submit a sample to the registry. We got this part synthesized from IDT and submitted a sample to the registry.
One of the most used chromoprotein used in iGEM is AmilCP blue, BBa_K592009. Because our modelling team was doing homology models for other proteins and AmilCP doesn't have a homology model on it's page, we decided to do one for AmilCP blue.
Click here to check out our modeling page!
