Japanese researchers have found a bacteria that appears to have evolved to consume PET, a common polymer used in plastics, New Scientist reports. The discovery could be used to develop new ways to tackle the earth's growing plastic waste problem.
Some plastics can take between 450 and 1000 years to decompose, but items made with polyethylene terephthalate (PET) stick around for much longer. PET plastic never biodegrades, which is what makes the discovery of this new bacteria, dubbed Ideonella sakaiensis, so remarkable. According to the study recently published in Science, it took the organisms six weeks to break down a thumbnail-sized sliver of PET at 30° C in lab tests. To degrade the material, I. sakaiensis latches on with its thread-like appendages. It uses just two enzymes to break down the PET into its environmentally-friendly chemical components, which it then makes into a meal.
Researchers stumbled upon the bacteria while studying the microbes living on discarded PET products the researchers had salvaged. The team believes the bacteria consumes PET alone, and the fact that these plastics have been around for less than 80 years suggests they evolved this adaptation relatively recently.
Over 5 trillion pieces of plastic, weighing a total of 269,000 tons, are estimated to be clogging up our planet's oceans. The scientists are hoping their discovery could inspire new ways of dealing with plastic pollution, possibly through the use of genetic engineering. While six weeks is a long time to spend chowing down on one piece of plastic, transferring I. sakaiensis's enzyme-producing genes to E. coli bacteria might help to speed up the process. You can read the full report in the March 11 issue of Science.