Microplastics refer to plastic particles less than 5mm in diameter, usually derived from the degradation of plastic products, industrial production and waste from daily life. Microplastics not only are widely found in water, but also enter the soil and atmosphere, posing potential threats to the ecosystem.
The widespread presence of microplastics has profound implications for human health and the environment. They may enter the human body through the food chain, causing physiological and health problems. In addition, microplastics can affect water ecology and disrupt the stability of biological habitats and food chains.
Current methods for treating microplastics mainly include physical filtration, chemical degradation and biodegradation. However, these methods often face problems such as high cost, low efficiency, and secondary pollution. Hence, more efficient and sustainable solutions are urgently needed.
This year the focus of the HUST-UEVE-UPSaclay team was to develop an efficient and sustainable solution to degrade microplastics. Our team has conceived a novel method that uses two systems to achieve microplastic degradation – engineered bacteria (E. coli) and engineered Caenorhabditis elegans (C. elegans). First, an engineered E. coli 1 is designed to specifically degrade PET microplastics into the recyclable monomer TPA. Another E. coli 2 is designed to consume this TPA by transporting and retaining the TPA. Next, C. elegans is engineered to consume the E. coli. to prevent the growth and spread of engineered E. coli in the natural environment. The C. elegans can be removed from water bodies by simple filtration, thereby ensuring that there is no secondary contamination and safety issues from engineered bacteria and TPA molecules.
This project aims to develop a new method for microplastic treatment based on engineered E. coli and C. elegans. We will achieve biodegradation of PET by using the enzyme PETase. The expression of a transporter and biosensor within E. coli will efficiently transport the treated monomeric TPA into E. coli in vivo. Subsequently, engineered nematodes will further consume the E. coli and enrich TPA, and recycle TPA after being filtered . Our team's innovative approach will not only help solve the problem of microplastic pollution, but also provide a new method for the recycling of plastic resources which is efficient and sustainable.
In the future, we hope to optimize the performance of E. coli and improve the efficiency of PET treatment through continuous research and development. At the same time, we will also explore the application of the nematode recovery engineering bacteria technology to other types of plastic treatment, to contribute to environmental protection and sustainable development..