Linking two enzymes turns plastic-eating bacteria into super-digesters
Plastic is . Scientists have found tiny bits of microplastic even in the extremes of the Earth – from the to the – and . While can be one of the most effective ways to reduce plastic waste, how do we deal with all of the plastic that already exists, polluting our oceans and overflowing out of landfills?

Polyethylene terephthalate, also known as PET and one of the most common types of plastic, is unfortunately notoriously difficult to break down. In 2016 however, outside of a bottle-recycling facility capable of decomposing plastic. The discovery revealed that the bacteria's abilities depend on two specific enzymes. These enzymes work together in a two-step process to break plastic down into smaller molecules that the bacteria can turn into energy.
published in the Proceedings of the National Academy of Sciences demonstrates a way to improve the two-enzyme system. While naturally existing as two separate enzymes – PETase and MHETase – the researchers physically linked them together. The attached enzymes worked together more efficiently than the same two enzymes when unlinked. Depending on the length of the linking segment between them, the attached enzymes were able to release almost double the amount or more of the final broken down product.
With this process, PET, could be broken down by the bacteria in days, a process which would take hundreds of years in the environment.
But breaking down plastic only deals with part of the issue of plastic waste. Recovering the plastic waste already in the ocean and other corners of the planet to deliver to recycling or decomposing facilities remains a daunting challenge. And even faced with the knowledge that we need to reduce plastic, the world has only been . Although these results are exciting, we're still far from solving our growing plastic problem.
This story originally appeared on , an editorial partner site that publishes science stories by scientists. to get even more science sent straight to you.

Enjoy reading ASBMB Today?
Become a member to receive the print edition four times a year and the digital edition monthly.
Learn moreGet the latest from ASBMB Today
Enter your email address, and we鈥檒l send you a weekly email with recent articles, interviews and more.
Latest in Science
Science highlights or most popular articles

Spider-like proteins spin defenses to control immunity
Researchers from Utrecht University discovered two distinct binding modes of a spider-shaped immune inhibitor found in serum.

A biological camera: How AI is transforming retinal imaging
AI is helping clinicians see a more detailed view into the eye, allowing them to detect diabetic retinopathy earlier and expand access through tele-ophthalmology. These advances could help millions see a clearer future.

AI in the lab: The power of smarter questions
An assistant professor discusses AI's evolution from a buzzword to a trusted research partner. It helps streamline reviews, troubleshoot code, save time and spark ideas, but its success relies on combining AI with expertise and critical thinking.

Training AI to uncover novel antimicrobials
Antibiotic resistance kills millions, but César de la Fuente鈥檚 lab is fighting back. By pairing AI with human insight, researchers are uncovering hidden antimicrobial peptides across the tree of life with a 93% success rate against deadly pathogens.

AI-designed biomarker improves malaria diagnostics
Researchers from the University of Melbourne engineered Plasmodium vivax diagnostic protein with enhanced yield and stability while preserving antibody-binding, paving the way for more reliable malaria testing.

Matrix metalloproteinase inhibitor reduces cancer invasion
Scientists at the Mayo Clinic engineered a TIMP-1 protein variant that selectively inhibits MMP-9 and reduces invasion of triple-negative breast cancer cells, offering a promising tool for targeted cancer research.