https://phys.org/news/2024-01-bacteria-plastic-multipurpose-spider-silk.html
Move over Spider-Man: Researchers at Rensselaer Polytechnic Institute have developed a strain of bacteria that can turn plastic waste into a biodegradable spider silk with multiple uses.
Their new study, published in Microbial Cell Factories, marks the first time scientists have used bacteria to transform polyethylene plastic—the kind used in many single-use items—into a high-value protein product.
That product, which the researchers call "bio-inspired spider silk" because of its similarity to the silk spiders use to spin their webs, has applications in textiles, cosmetics, and even medicine.
"Spider silk is nature's Kevlar," said Helen Zha, Ph.D., an assistant professor of chemical and biological engineering and one of the RPI researchers leading the project. "It can be nearly as strong as steel under tension. However, it's six times less dense than steel, so it's very lightweight. As a bioplastic, it's stretchy, tough, nontoxic, and biodegradable."
All those attributes make it a great material for a future where renewable resources and avoidance of persistent plastic pollution are the norm, Zha said.
Polyethylene plastic, found in products such as plastic bags, water bottles, and food packaging, is the biggest contributor to plastic pollution globally and can take upward of 1,000 years to degrade naturally. Only a small portion of polyethylene plastic is recycled, so the bacteria used in the study could help "upcycle" some of the remaining waste.
Pseudomonas aeruginosa, the bacteria used in the study, can naturally consume polyethylene as a food source. The RPI team tackled the challenge of engineering this bacteria to convert the carbon atoms of polyethylene into a genetically encoded silk protein. Surprisingly, they found that their newly developed bacteria could make the silk protein at a yield rivaling some bacteria strains that are more conventionally used in biomanufacturing.
[...] "What's really exciting about this process is that unlike the way plastics are produced today, our process is low-energy and doesn't require the use of toxic chemicals," Zha said. "The best chemists in the world could not convert polyethylene into spider silk, but these bacteria can. We're really harnessing what nature has developed to do manufacturing for us."
Journal Reference:
Alexander Connor et al, Two-step conversion of polyethylene into recombinant proteins using a microbial platform, Microbial Cell Factories (2023). DOI: 10.1186/s12934-023-02220-0
(Score: 2) by Username on Monday January 29 2024, @05:44PM
It's fine, places like Wuhan never leak dangerous global contagions.