A Bio Solution To Plastic Pollution
More than 8 million tons of plastic are being dumped into the ocean each year from runoff and wastewater treatment, much of which are small particles called microplastics (Boucher, 2017). Microplastics tend to bind to common toxins in the water, which congregates all of the toxins in one place. This is detrimental to the health of ocean life. When fish and other creatures unknowingly consume the microplastics, they are exposed to the harmful toxins and to the side effects of the nondegradable plastic in their stomachs. The toxins not only stay in the fish, but they also move up the food chain and can affect everything along the way, including humans. Today, 98% of people test positive for toxins commonly found in plastic. To help eliminate this problem, our team will attempt to make a plastic degrading microbe (Yoshida et al, 2016) that can attach to the microplastics in wastewater and break them down before they are released into the ocean. In order to attach to the plastic, the microbe will excrete a curli protein induced by toxins that commonly bind to the microplastics. A PETase enzyme with a different active site (Austin et al, 2018) to increase the reaction rate will be used to break down the plastics to simpler compounds. These compounds can be used for energy by the cell, so no further processes are necessary. Ideally, our synthesized microbe will be placed into the wastewater treatment process to eliminate the plastic waste that surpasses existing treatment processes. A currently used process in wastewater treatment already exists where bacteria and biological organisms break down the organic particles in the water, so our microbe could be implemented into this process fairly easily.
Austin, H., Allen, M., Donohoe, B., Rorrer, N., Kearns, F., Silveira, R., . . . Beckham, G. (2018). Characterization and engineering of a plastic-degrading aromatic polyesterase. Proceedings of the National Academy of Sciences of the United States of America, 115(19), 4357. doi:10.1073/pnas.1718804115
Boucher, J.; Friot, D. Primary Microplastics in the Oceans: A Global Evaluation of Sources; IUCN: Gland, Switzerland, 2017.
Yoshida, S., Hiraga, K., Takehana, T., Taniguchi, I., Yamaji, H., Maeda, Y., . . . Oda, K. (2016). A bacterium that degrades and assimilates poly(ethylene terephthalate). Science, 351(6278), 1196-1199. doi:10.1126/science.aad6359