A protein dubbed ‘Pac-Man’ has been found to eat up plastic and break it down in such a way that it could open the door to eliminating tons of landfill waste.
The catalyst destroys PET (polyethylene terephthalate), which is omnipresent in everyday food and drink packaging, carpet fibers, and textiles. It offers hope for tackling worldwide contamination by supercharging recycling on a massive scale. Major industries would now have the option to recover and reuse items at the molecular level.
This is a good thing considering that the largest landfill in America is located in The Puente Hills. It has over 150m (490 ft.) of garbage that has risen up from the ground since the area became a designated landfill in 1957.
“The possibilities are endless across industries to leverage this leading-edge recycling process,” said Professor Hal Alper, from The University of Texas at Austin. “Through these more sustainable enzyme approaches, we can begin to envision a true circular plastics economy.”
PET makes up 12% of all worldwide waste. Like all plastics, it’s comprised of long string-like atoms. The enzyme reduces them into smaller parts – synthetics which can then be reassembled. Now and then, the plastics can be completely separated in only 24 hours. The computer distinguished those that would be most effective at less than 50 degrees Celsius (122-F), making it both portable and reasonable in price.
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Artificial intelligence, machine learning, generated novel mutations to a protein called PETase that allows microscopic organisms to degrade PET.
Prof. Alper and his associates examined many of the discarded plastic items including water bottles and polyester fibers and fabrics which were all made from PET. Tests demonstrated the viability of the compound named FAST-PETase (functional, active, stable and tolerant PETase), and a paper was published last week describing the chemical in the journal Nature.
“This work really demonstrates the power of bringing together different disciplines, from synthetic biology to chemical engineering to artificial intelligence,” said co-author Andrew Ellington, a professor in the school’s Center for Systems and Synthetic Biology whose team led the development of the machine learning model.
Other alternative industrial processes for separating plastic are energy-intensive, but organic solutions such as this require significantly less.
Research on chemicals for plastic recycling has progressed during the past 15 years. However, not too long ago, nobody had been able to figure out how to make chemicals that could work effectively at such low temperatures to make them both affordable and portable at large industrial scale.
The best part is that the US team have documented a patent and production is being scaled up to get ready for industrial applications. Cleaning up landfills and greening high waste-producing industries are the most obvious. But another key potential use is natural remediation. The scientists are taking a look at a number of various ways to use the compounds in the field to not only tidy up, but actually clean up polluted sites.
“When considering environmental clean-up applications, you need an enzyme that can work in the environment at ambient temperature. This requirement is where our tech has a huge advantage in the future,” said Alper.