Plastic pollution is one of the major environmental emergencies that we are facing globally. To recycle the waste, several SynBio methods had been proposed, but they were limited to the POC level or in-vitro experiments.
My aim is to develop a plan for enabling large-scale plastic recycling at a self-sustaining (profitable) manner. To do so, I intend to employ plastic eating maggots. By engineering their efficiency at plastic recycling, plastic waste then can be used as a fodder. Finally, maggot population can be utilized as a fodder to livestock and as a pet food. In rare cases, for producing protein bars for those gym-goers that are willing to do the right thing 😁😅.
The latter can be done by engineering the metabolic networks of the gut bacteria of the plastic-eating maggots, to promote the symbiosis for plastic recycling.
While it can be made extremely unlikely for an engineered maggot to leave the recycling factory, by instilling good practices at the designated operating environment (DOE), it is still essential to make sure that shall there be an incident, it won’t lead to another environmental catastrophe. Previously, researchers have demonstrated methods to create organisms that are unable to sustain themselves without engineer-provided invented materials such as artificial amino acids (https://hms.harvard.edu/news/no-escape). Such approach of engineering can also be applied to maggots, ensuring their destruction outside the DOE.
Other means to promote maggot identification outside the DOE, could be by adding a fluorescent biomarker to their chitin, making them easier to spot with a UV light. In addition, DOE can be set up in areas that are naturally destructive for maggots, such as dry, hot and freezing environments, shall global warming allow it.
Currently plastic waste can largely be mishandled or reused by melting or shredding or other processes that are also heavily relied on largely fossil-generated energy. Maggot-mediated plastic recycling will feature an eco-friendly solution that will also be a sustainable business model.
Research will be needed to understand key compounds that promote maggot growth. These compounds should be then produced by the bacteria intended to become a mutualistic “parasite” of the maggots. This will require metabolic engineering of the gut bacteria for both production of essential compounds for maggot survival and for the digestion of the plastic waste that ends up in the maggot gut. In addition, maggots should be unable to otherwise survive without these bacteria and vice-versa, bacteria should also be unable to survive without the maggot. Their symbiosis should be made obligatory.
It might be that the business model won’t work. Firstly, deeper study must be done over feasibility of selling such a product. Some nations also would not like to see the GMO food fed to their livestock.
In addition, obviously, a maggot protein bars will likely not be sold, but if any credit is to be given to the nature of modern environmentalists, I might just be wrong about that too.
Finally, engineering obligate mutualism might be tricky and knocking out certain genes may not be sustainable considering the speed of replication of both the maggots and the bacteria. This would mean that regular genetic tests may have to be applied, to ensure that desired genetic setting is maintained.