American researchers have created genetically modified bacteria that can break down strong plastic. It is interesting that in the process of using the material, microorganisms give it even greater hardness, but after reaching the landfill they will soon decompose it.

Plastic is a universal material of our age: it is cheap, resistant to chemicals and strong. But it is the last property that makes it very difficult to dispose of. Plastic takes tens, sometimes hundreds of years to decompose; Therefore, such waste pollutes the earth and oceans. That’s why scientists around the world are constantly thinking about how to break down plastic most efficiently, and in recent years bacteria that can do this have been discovered.

Rhodococcus ruber, for example, can feed on plastic and destroy 1.2 percent of the weight of polyethylene entering the world’s oceans each year. However, this requires appropriate environmental conditions, and the plastic itself that bacteria can break down is generally soft. Things are much more difficult with a strong material like thermoplastic polyurethane, which is used to make shoes, car parts, phone cases and many other everyday products. So far, such plastics cannot be recycled in any way.

Scientists from the University of California, San Diego (USA) decided to deal with this problem. They turned their attention to the hay bacillus (Bacillus subtilis), a type of gram-positive bacteria obtained from hay extract. At the same time, bacteria are found everywhere, from the intestines of humans and animals to the air and water. These microorganisms can break down plastic.

The researchers suggested that Bacillus subtilis be incorporated into the material itself. The interesting thing is that bacteria do not break down plastic until it reaches the landfill and comes into contact with soil. The plastic has to be literally buried in the compost for it to start producing enzymes. Therefore, you can use such products as much as you want. But there is a problem; The high temperatures used in plastic production kill most bacterial spores.

So scientists created the heat-tolerant GMO microbes Bacillus subtilis and found that 96 to 100 percent of the spores of such bacteria could survive the plastic processing temperature of 135 degrees Celsius. This is a very promising result, since non-genetically modified bacteria can only survive this type of heating by 20 percent.

After that, the researchers tested how well Bacillus subtilis broke down plastic. It turned out that at a concentration of up to one percent of the weight of the plastic, microorganisms broke down more than 90 percent of the material within five months of composting. Scientists have discovered another neat advantage: Plastic made with Bacillus subtilis is 37 percent stronger and 30 percent less prone to tearing than traditional thermoplastic polyurethane. Thus, bacterial spores act on the material in a similar way to a reinforcing filler. The study was published in the journal Nature Communications.