Preventing Plastic Pollution with Engineering Biology (P3EB) Mission Hub

Plastics are synthetic polymers - chains of building blocks linked together by chemical bonds - that are not naturally found in the environment, whereas natural polymers are commonplace in all kingdoms of life. For every natural polymer, there is a natural biological machine, termed an enzyme, that can deconstruct it back into its constituent building blocks (monomers). These deconstructing enzymes give circularity to life; the building blocks can be reused with nothing going to waste or being lost. When plastics were introduced over the last century, they were designed to be durable, and it is this characteristic that makes them so essential to modern life. However, this durability means that it requires a lot of energy to deconstruct plastics, something that natural enzymes find really challenging to do. This means that plastic waste, once in the environment, becomes a persistent pollutant harming wildlife, threatening human health, and becoming a rapidly increasing environmental concern. To address this problem, we need technical solutions to repurpose plastics when they reach the end of their life as waste; and to redirect their monomers to higher quality goods.

The Preventing Plastic Pollution with Engineering Biology (P3EB) Mission Hub brings together an exceptional group of researchers and innovators to tackle the urgent environmental challenge of plastic pollution and create new ways for plastics to be deconstructed sustainably, much like natural polymers. Our team has established several impactful engineering biology platforms for making enzymes and microbes perform better at chosen tasks. By expanding these platforms towards the deconstruction of a wide range of plastics, we will develop environmentally friendly, innovative methods to create high-value products from waste. These efforts will support UK businesses in meeting their carbon reduction goals, contribute to sustainable clean growth, and help incentivise plastic waste recovery and recycling to prevent pollution and the use of fossil fuels, from which most plastics are derived.

In the P3EB Mission Hub, our focus is on plastics that are linked together by bonds between carbon and either oxygen or nitrogen atoms (C-O/N), similar to the way many polymers in nature are constructed. Enzymes can break these types of bonds in one step, making C-O/N plastics the ideal starting point to develop efficient industrial processes. Out of this group of plastics, we will target those that cause the most harm to our environment and are the most produced, namely PET, polyurethane, polycarbonate and nylon. Alongside this work, we will develop sustainably sourced monomers to make future recyclable-by-design plastics, in support of the transition to a circular plastics economy.

Currently, enzymatic plastic recycling is not sufficiently sustainable, and one of the P3EB Mission Hub goals is to address this. We will establish standards for measuring enzyme performance, discover new enzymes that break down the target plastics, and engineer enzymes and microbes for improved deconstruction. We also seek to improve industrial PET recycling and develop ways to reduce its energy use. Additionally, we will expand the range of valuable products that can be made from plastic monomers and engineer microbes to produce them sustainably. Finally, to ensure the widespread adoption of our technologies, we will engage with the public, policymakers and industry stakeholders.

The P3EB Mission Hub combines expertise from leading UK universities and research institutions, bringing together diverse capabilities in plastic waste research, enzyme engineering, and sustainable materials. Our track record includes significant contributions to enzyme discovery, plastic waste upcycling, and waste policy. By working together, we aim to achieve a future where plastic does not become waste, and can even be turned into a more valuable material.

The P3EB Mission Hub combines engineering biology and waste expertise to tackle plastic pollution by enhancing the value of post-consumer plastic waste, incentivising its recovery and repurposing. We will advance biotechnology for the deconstruction and upcycling of plastics, as well as decarbonising their feedstocks. We aim to develop efficient, low energy pipelines for plastic biorecycling that deploy engineered enzymes and microbes in processes shaped by the public, policy and our industrial partners.

To achieve this, our mission focus is on C-O/N bonded polymers which contain labile bonds and in principle can be depolymerised by enzymes with a single step under mild conditions, providing the ideal starting point for the development of sustainable biorecycling processes. We will leverage and extend our engineering biology toolbox incorporating metagenomic and machine learning approaches to enzyme discovery, HTP screening, rational and computational methods for enzyme design, metabolic and microbial engineering, as well as laboratory evolution. Grounded by life cycle analyses, we will: engineer enzymes to maximise their industrial efficiencies on target C-O/N plastics; develop microbial strains and hybrid chemoenzymatic approaches capable of valorising plastic monomers and generating sustainable feedstocks; and streamline existing and new approaches for plastic biorecycling at industrial scales with a focus on minimising environmental footprint. Finally, we will empower technology transfer by setting clear procedural standards and cross-validating technologies both within and beyond the hub, and maximize acceptance and commercialization of our engineered biological products through dialogue and collaboration with the public, policymakers and industry.

Crucially, we will realise a vision where plastics are sustainably sourced, their production decoupled from fossil fuels, and where waste is turned into high value products through engineering biology.