In 2016, a bacterium that is capable of eating plastic. Since then, researchers have been trying to understand how it works, wondered about its evolution and capabilities. Will the plastic-eating bacteria help us solve the problem of plastic waste and microplastics? The research is still in progress.
THE BACTERIUM EATS PLASTIC: THE DISCOVERY
In Japan, in a landfill, a microorganism capable of degrading the polyethylene terephthalate, that is the plastic most widely used plastic on the market, known as PET. This type of material is used to produce disposable items that we throw away every day, such as food containers or water bottles, which have generated a serious environmental problem linked to theplastic pollution. The problem is that plastic takes hundreds of years to biodegrade and the waste wander the planet, polluting seas and oceans for a long time. In addition, more and more research is being carried out on microplastics and the damage they can create to ecosystems and the health of all species on the planet. So, the discovery in 2016 of proto-bacteria capable of degrade this material shocked the scientific community. In a very short time the Ideonella sakaiensis have caught everyone's attention.
HOW DOES THE PLASTIC-EATING BACTERIUM WORK?
Once the existence of a bacterium capable of digesting plastic they immediately began to study it, especially in search of new strategies to solve the problem of plastic waste disposal. plastic waste disposal. So how does this bacterium work? PET, polyethylene terephthalate, is for these bacteria bacteria a real food source. They have adapted to the new living conditions that the environment has offered them and have begun to use this material as a nutrient source. They have made an amazing evolutionary leap in only about seventy years. The bacterium exploits two enzymes: initially it adheres to the material and secretes the enzyme PETase which divides it into small pieces; then a second enzyme comes into play, the MHET hydrolase which splits the material to make it a nutrient. This action splits the plastic into two elements: ethylene glycol and terephthalic acid. They become a source of carbon for the bacterium that feeds on them.
RESEARCH ON THE PLASTIC-EATING BACTERIUM
Research has shown that the functioning of the plastic-eating bacteria and the set of enzymes that exploits are unique in their kind, if they were the result of an evolutionary path this has happened in a very short time, more reason to make scholars even more interested in the bacterium. Further investigation has shown that the nutritional process of this bacterium is very slow as it takes about six weeks to degrade about 60 mg of plastic at an optimum temperature of 30 °. This ability was unknown in nature before the 2016 discovery and this has led many to question the possibility of solve the problem of pollution thanks to the plastic-eating bacteria.
IS THE PLASTIC-EATING BACTERIA A SOLUTION?
Despite the great interest aroused by the bacteria plastic-eating bacteria and the numerous researches carried out, it is necessary to wait for further studies to understand if there will be effective uses of the bacteria. It is speculated that they may be used in the recycling path of the material as they break down plastic into two simpler components. Studies have shown that by allowing the bacteria to proliferate in about five months the weight of the plastic was reduced by up to 7%. To date, however, those to be disposed of are entire islands of plastic waste and so the strategy to be used is not yet clear. Certainly the prospects are good and interesting, the world of research still has much to discover.