by2050: Superbug that eats plastic

Recently, non-recyclable microplastic particles (MPPs) derived from commonly-used plastics is a widespread problem across the globe. We are committed to solving this problem through biodegradation, converting MPPs into reusable plastic building blocks. It has been discovered that certain bacteria, algae, and fungi can degrade plastics. We intend to combine the power of the plastic-degrading features from each microorganism into a new organism through genetic engineering. This new organism could degrade MPPs derived from a variety of plastics and potentially degrade them more efficiently. We want to design a two-part device called the microplastic eliminator (MPE). The first part of the MPE degrades MPPs using the engineered microorganism, while the other part collects the degraded products. These building blocks can be used to make recyclable plastic products, therefore reducing the need to produce new plastic. This will contribute to solving the worldwide plastic waste problem.

Plastic is a common type of material that is used in a lot of the things we use in our daily lives, but it is largely not reusable. Plastic waste is a problem because it invades the food chain, negatively impacts human health, and damages the ecosystem. It takes decades to thousands of years to decompose plastics. About 300 million tons of plastics are produced globally each year. Efforts like encouraging everyone to consume less plastic and recycle are being made to manage plastic waste problem. However, only about 10 percent of it is actually recycled. Plastic waste is a problem everyone faces in our everyday life. One particular threat that cannot be solved by recycling, is the breakdown product of plastic waste called microplastic particles, which can easily enter the human body to disrupt our bodily functions. We want to create a device called microplastic eliminator (MPE) to degrade MPPs and turn them into renewable and recyclable raw materials. The conversion of MPPs into reusable materials will reduce the need to generate the plastic from natural gases and oil. It can also reduce the potential health risks in our ecosystem.

Every person in the world uses plastic, one way or another. Single use plastic products are constantly being disposed of, which creates lots of waste. In addition, MPPs create health concerns. Once MPPs enter the human body, it could lead to multiple problems: damage to the kidney filtration process, inflammation when the immune system tries to eliminate them, damage to the organs (lungs, heart, liver, etc.) if MPPs enter them. These MPPs, could also stick to endothelium of blood vessels and clot the blood capillary. Any person that takes in the MPPs contaminated foods and/or drinks is exposed to these threats. MPE will degrade MPPs into plastic building blocks to reduce the waste and health risks. To bring awareness to this problem, I can create posters and give talks to local schools in my area. I also want to gain the support of my community to test my device in our township and engage professors in the field to provide support to experiment with this idea. This project could potentially create a cleaner environment for the people in our township. If successful, it can be scaled up to help millions of people worldwide.  

Several new microbes (fungi, bacteria, algae) have been found that are able to degrade plastic material(s) and use it as carbon source. The ones we researched are Aspergillus tubingensis and I. sakaiensis that contains two key enzymes PETase and MHETase that degrade PET. PETase breaks PET down into MHET. MHETase breaks down MHET into terephthalate and ethylene glycol.  In addition, new PETase have been identified through bioinformatics and experimentation. My proposal is a device that I call MPE that utilizes the plastic-degrading powers of bacteria.  The first goal is to focus on degrading polyethylene terephthalate (PET), an important, synthetic polymer that makes up at least 20% of the world’s plastic. Biodegradation of PET involves using alpha- and beta-hydrolases. The 3D structure of I. sakaiensis PETase and MHETase have been solved. After finding the genes encoding the enzymes from other people’s research, we will transfer these genes with the proper procedures into one bacteria and optimize the expression and functions of these enzymes. This is a long process of genetic engineering and we need the molecular biology tools and common microbiology lab equipment for these processes (DNA purification kit, selection markers, genome editing etc.) to make this microorganism. These would be the microorganisms in the MPE.  Armed with transferred genes, the microorganism will possess the ability to degrade/digest the MPPs from common types of plastic waste. Then, we will grow the microorganism in plastic waste processing container (or pool) with other necessary supporting nutrients to let it amplify itself. The bacteria would grow and consume the corresponding plastic wastes and convert them into reusable less/non harmful substances. We will conduct lab and field tests to test the efficiency of our device to digest multiple types of plastic.