Water bottles, food packages, supermarket bags… we all use them on our day to day and, in the vast majority, they’re all made from plastic. Just in Europe, we are consuming over 50 million tonnes of plastic each year: nearly 100 Kg of plastic for each one of us! In the face of this environmental and societal challenge, there are two main ways in which we can help reduce the impact that plastics have. We can decrease the amount of plastics we consume and increase our recycling efforts. While the first measure is being implemented across Europe through the European Strategy for plastics, an uncanny ally can help us with the second one: bacteria.

Bacteria are avid trash converters. In nature, they turn organic waste into rich compost for the soil. At Rafts4Biotech, we are working also with bacteria so they can turn industrial waste into harmless and useful compounds in our feed study case. And other researchers are applying the latest advances in synthetic biology to tackle the plastic challenge. This was the case of P4SB, a European project that has been investigating how to tweak the bacteria Pseudomonas putida into eager eaters that turn plastic waste into valuable and biodegradable materials.

Since not all plastics are equal, P4SB narrowed the scope of its project to two of the main plastics we use: PETs and polyurethane (PU). First, they studied how to break down the bottles and wrappers we consume at home down to the long chains of molecules that compose them: the polymers. These compounds are like microscopic beaded necklaces, with each bead (scientists called them monomers) being the same molecule, repeated over and over again. These long chains are still too big to be fed directly to the bacteria, so the researchers at P4SB selected a group of enzymes that are able to breakdown the polymers into individual monomers, ready to be devoured by a group of selected Pseudomonas putida.

Since the typical Pseudomonas putida we can find on the streets doesn’t metabolise monomers for a living, the researchers developed a series of strains that converted these molecules to more basic ones, producing bioplastics and other chemical products useful for the industry.

The P4SB project came to an end last March, and has left an excellent set of results that you can consult at their webpage. They are a good example of how European research can foster fruitful collaborations among many different countries and profiles, to bring technologies that may seem science fiction closer to reality, helping us tackle the current environmental crisis.