The continuing demand for plastic products, the lack of appropriate recycling and the ubiquitous pollution of the environment with plastic waste pose a global challenge. An ambitious vision and considerable efforts are required to change the traditional value chain of plastics to a sustainable one, based on biodegradable plastics. In MIX-UP, plastic mixtures with five of the top six fossil-based recalcitrant plastics (PP, PE, PUR, PET, and PS), along with upcoming biodegradable plastics such as PLA and PHA, will be used as feedstock for microbial transformations, thereby generating a workflow that increases the recycling quota and adds value to poorly recycled plastics waste streams. Successive controlled enzymatic and microbial degradation of mechanically pre-treated plastics waste will be combined with subsequent microbial conversion to value-added chemicals and polymers by mixed cultures. We will optimize known plastics-degrading enzymes for high specific binding capacities, stability, and catalytic efficacy towards a broad spectrum of plastics polymers under high salt and temperature conditions by integrated protein engineering, and also isolate novel enzymes with activities on recalcitrant polymers. MIX-UP will also optimize the production of enzymes and formulate enzyme cocktails tailored to specific waste streams. Implementation of these enzymes, both in vitro and in vivo, enables stable self-sustaining microbiomes to convert the released plastic monomers selectively into at least six value-added products, key building blocks, and biomass. Any remaining material recalcitrant to enzymatic activity will be recirculated into the process after a physico-chemical treatment. The Chinese-European MIX-UP is a multidisciplinary and industry-driven consortium that addresses the market need for novel sustainable routes to valorise plastics waste streams. MIX-UP realises a circular (bio)-economy and could be a viable alternative for mechanical and chemical recycling.

P4SB is about the utilization of the conceptual and material tools of contemporary Synthetic Biology to bring about the sustainable and environmentally friendly bioconversion of oil-based plastic waste into fully biodegradable counterparts by means of deeply engineered, whole-cell bacterial catalysts. These tools will be used to design tailor-made enzymes for the bio-depolymerization of PET (polyethylene terephthalate) and PU (polyurethane), but also for the custom design of a Pseudomonas putida Cell Factory capable of metabolizing the resulting monomers. Pseudomonas putida will undergo deep metabolic surgery to channel these diverse substrates efficiently into the production of polyhydroxyalkanoates (PHA) and derivatives. In addition, synthetic downstream processing modules based on the programmed non-lytic secretion of PHA will facilitate the release and recovery of the bioplastic from the bacterial biomass. These industry driven objectives will help to address the market need for novel routes to valorise the gigantic plastic waste streams in the European Union and beyond, with direct opportunities for SME partners of P4SB spanning the entire value chain from plastic waste via Synthetic Biology to biodegradable plastic. As a result we anticipate a completely biobased process reducing the environmental impact of plastic waste by establishing it as a novel bulk second generation carbon source for industrial biotechnology, while at the same time opening new opportunities for the European plastic recycling industry and helping to achieve the ambitious recycling targets set by the European Union for 2020.

Nature has hardly evolved biochemical reactions involving fluorine (F), the most abundant halogen on Earth. Organic compounds containing F (fluorochemicals) are, however, extremely relevant from an industrial point of view. Fluoropolymers are the main fluorochemicals in the market worldwide, and are exclusively synthesized using chemical methods. Moreover, current fluorination technologies usually involve corrosive and toxic reagents that have a negative impact on the environment. Designing sustainable bioprocesses based on alternative and safer fluorinating agents from renewable substrates is thus a long-sought-after, yet unfulfilled goal. SinFonia proposes to engineer the metabolically-versatile bacterium Pseudomonas putida to execute biofluorinations for generating novel fluoropolymers from renewable substrates. P. putida KT2440, a non-pathogenic soil bacterium, serves as an ideal microbial platform for F-dependent biochemical reactions due to its extraordinary resistance to harsh and stressful operating conditions. SinFonia will exploit natural selection to enhance bioproduction through a smart strain engineering approach in which bacterial growth will be coupled to biofluorination. Our target compounds are a whole family of fluorinated polyesters with enhanced physicochemical and material properties, with uses as self-cleaning surfaces, low-surface-energy coatings, bio-based lubricants, membranes for fuel cells, and anti-fouling materials. The versatile P. putida strains engineered during the project can be easily adapted to synthesize other added-value fluorochemicals. Unlike chemical processes, the source of F in our system will be NaF, an inexpensive and safe salt, and sugars as the main carbon source. In-depth analysis of all the environmental and economic benefits of the new fluorination technology, and interactive communication of social benefits associated with target products, are essential components of SinFonia.

Recycling facilities are currently struggling when dealing with challenging plastic multi-layers, blends, and additives. Consequently, packaging plastics are mostly landfilled, incinerated or spilled into the environment. The concept of UPLIFT is to introduce biological depolymerization technology as an addition and integration to established recycling practices, by converting persistent plastic waste into more easily recyclable and/or degradable polymers. The project will start by analyzing the value-chains of the future to match and exploit the potential of microbe-and enzyme technology to effectively depolymerize the EoL plastic into monomers. Overall, the project aims at engineering towards greater scale and efficiency. Moreover, in order to contribute to further innovation, UPLIFT will also make use of an advanced high-throughput screening platform to further explore the potential of new and more efficient biocatalysts, among bacteria, yeasts and fungi. Synergies between genetic and protein engineering, as well as eco-engineering of microbial mixed consortia will be under Uplift’s scope. Furthermore, the knowledge of bio-depolymerization will be strategically applied for the eco-design and development of renewable and easy-recyclable polymers, thus making plastic packaging an available feedstock for the circular economy. Introducing biological depolymerization to current recycling practices will increase the capability of dealing with large amounts of currently non-recycled plastics. By doing so, UPLIFT will contribute and facilitate the transition to more efficient recycling facilities, thus paving the way to a sustainable plastic system.