Riccardo Liguori Thanks to bioengineering, the modified bacterium from the Jülich Research Centre could reduce microplastic pollution and give new life to textile waste and fishing nets
@Canva
From the clothes we wear to fishing nets and industrial components, nylon is everywhere. But recycling it is nearly impossible, leading to significant environmental pollution. Now, a groundbreaking discovery could change everything: a genetically modified bacterium can break down nylon and transform it into biodegradable plastic. Could this be the breakthrough for a circular economy?
Although synthetic polyamides, known as nylon, are valued for their strength and versatility, their recycling remains an unsolved issue: less than 5% is recovered. Mechanical recycling techniques require pure nylon, while chemical recycling, though effective, produces compounds that are difficult to separate and reuse. As a result, vast amounts of nylon end up in landfills or are incinerated, with serious environmental consequences.
The solution
A team of researchers from the Jülich Research Centre, in collaboration with the company Novonesis, has genetically modified the bacterium Pseudomonas putida, known as KT2440, to metabolize nylon byproducts and convert them into a biodegradable bioplastic called polyhydroxybutyrate (PHB). This discovery, published in Nature Microbiology, marks a major step forward in the biological recycling of polyamides.
How the engineered bacterium works
Nylon, after undergoing chemical hydrolysis, dissolves into a mixture of monomers and oligomers. The modified Pseudomonas putida strain has been trained in the lab to metabolize these compounds, using them as a carbon source and converting them into PHB. This process overcomes the limitations of traditional chemical recycling since the bacterium almost completely consumes the dissolved plastic without requiring intermediate purification.
From polluting nylon to bioplastic
The PHB produced is a biodegradable plastic with various industrial applications, including packaging and compostable materials. Thanks to this technology, waste such as fishing nets and polyamide fabrics could be converted into new sustainable products, reducing plastic accumulation in the environment.
Scientific data
According to the study, global plastic production exceeded 880 billion pounds in 2022, with nylon accounting for approximately 22 billion pounds. However, the recycling rate for polyamide fibers is below 2%. The process developed by the researchers allows Pseudomonas putida to metabolize monomers such as ε-caprolactam and 1,6-hexamethylenediamine, which are essential in nylon production. Additionally, experiments have shown that the bacterium can produce up to 13.2% PHB by weight when fed with properly treated nylon waste.
This mechanism leverages genetic engineering to enhance the bacterium’s ability to digest these compounds and convert them into biopolymers without releasing toxic substances into the environment. The efficiency of the process has been successfully tested in the lab, and researchers are now studying how to scale it up for industrial use.
Challenges and future prospects
Although the research is promising, large-scale implementation remains a challenge. Scientists are working to improve the efficiency of the process and make it economically viable. In the coming decades, we could see the emergence of biological recycling plants capable of transforming millions of tons of nylon into biopolymers, reducing our dependence on conventional plastics and contributing to a more sustainable circular economy.
Genetic engineering has opened new doors for polyamide recycling, offering an innovative and eco-friendly solution for one of the most difficult materials to dispose of. If successfully implemented, this technology could revolutionize the recycling sector, turning nylon from an environmental problem into a valuable resource for a more sustainable future.
