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Managing byproducts of the extraction and refinement processes is a common problem in harvesting natural resources, such as oil. In most cases, tailings ponds are used for storing the toxic water byproducts, which not only have severe negative environmental impacts but also by using current methods can take decades before they can be reclaimed. The current remediation methods need to be improved to provide economical, effective and efficient processes to decrease the negative environmental impact of the tailings ponds. We will produce a tailings pond clean up kit that uses environmentally safe methods to accelerate the decontamination of toxic organic molecules, heavy metals, and settle the fine clay particles at an increased rate.
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Tailings ponds store mining waste including toxic organic compounds. Project stages: look at reducing fine clay particles, toxic organic compounds and ensuring cell viability.
- Reducing fine clay particles: strategy involves inducing e.coli to bind to clay particles and expressing Antigen43 so that they bind to each other and precipitate out of solution.
- Ensuring viability: Found that “nothing in tailings ponds that will kill e.coli outright”. Clashes with iGEMCalgary team’s similar experiment, who experienced a much slower growth rate as compared to LB broth.
- Toxic degradation: co-localizing metabolic enzymes in a micro-compartment to facilitate metabolic process using Lumazine synthase from Auifex aeolicus. Utilized mutant to generate negatively charged microcompartments.
Ethics – focussed on public awareness. Made a movie, “BioSpirits” about teams competing to win a contract from from a beer-brewing company. Protagonist uses water purified from tailings ponds to grow synthetic beer-producing trees. A movie provides accessibility ot public and the movie gives a context for technological and scientific innovation.
Accomplishments:
- Addressed safety issues with chassis (e.coli) using 2007 Berkeley iGEM’s killswitch part.
- Confirmed functionality of their sedimentation parts – took longer than expected, but it worked.
- Ensured viability of chassis in tailings pond water – found that there was not a a significant difference in growth with tailings pond water and LB broth.
- Created charged microcompartments which can localize positively charged molecules, characterized with electron and fluorescent microscopy.
- Where did the Lumizine synthase come from?
This was not engineered by the team, but we produced a biobrick from published research.
- When you get the system working, then what?
One method we could use is removing water from the tailings pond and putting it in a controlled bioreactor, so that saftey issues are better addressed.
- Can the toxic compounds enter the microcompartment?
Yes, the microcompartments are porous and allow for movement in and out by organic compounds. - What kind of % kill rate do you want with your killswitch?
We don’t think we should accept anything less than 100%. Even beyond that, safety measures can be added on top of that.
- Is there a lower temperature threshold for your Lumizine synthase?
We don’t know yet; our experiments were run at 37 deg C and we haven’t looked at the lower limits yet
