Magnetic Nanoparticles

Our team’s current project is to reduce the toxicity of the tailings ponds. One of the ways in which we plan to achieve this is through the reduction of naturally existing heavy metals into magnetite nanoparticles in parallel to breaking down harmful chemicals such a naphthenic acids. After sufficient decontamination other methods would then be utilized to continue the remediation of the tailings ponds. The gene we will implement to perform heavy metal decontamination codes for a protein known as Mms6 (Arakaki et al, 2010).

Mms6 is a protein naturally found in Magnetospirilum magneticum strain AMB-1 and has been shown to reduce aqueous iron into nanoparticles of magnetite (Fe₃O₄) (Aarakaki et al., 2010). The Lethbridge 2009 iGEM team submitted the Mms6 coding sequence and Mms6 expression construct to the Registry that we will work towards characterizing for the formation of nanoparticles. We intend to find the optimal Mms6 expression conditions in vivo by exploring different conditions such as in the presence and absence of iron, as well as with Mms6 localized to different parts of the cell such as the periplasm. Our team has four signal sequences that we will use in the future for this purpose, which can be used for Mms6 characterization in the future.

There are numerous applications in the medical, environmental, and energy sectors for magnetic nanoparticles. For our project we aim to decrease toxins in the tailings ponds, as well as give the bacteria an extra survival tool by reducing the concentration of heavy metals in the bacteria’s local environment.

References

Arakaki, A., Masuda, F., Amemiya, Y., Tanaka, T., Matsunaga, T. (2010). Control of the morphology and size of magnetite particles with peptides mimicking the Mms6 protein from magnetotactic bacteria. Journal of Colloid and Interface Science. 343:65-70.