The original intention of Stern Gustav Turing's invention of plastic bags is that compared with paper bags, plastic bags are not easy to be damaged by moisture and can be reused, thus reducing the felling of trees. However, contrary to expectations, it is estimated that more than half of plastic bags have not reached the original design intention of "reuse", and many plastic bags are discarded in nature at will. According to the statistics of the United Nations, the annual output of plastic bags in the world now reaches one trillion. The white pollution caused by plastic bags has brought severe challenges to the fragile environment of human beings. How to solve the white pollution caused by plastic bags has always been a subject that scientists have been studying.
At present, the most common plastic material in the world is polyethylene terephthalate (PET), which is widely used in clothing, bottled water and food packaging. However, it takes hundreds of years for PET to decompose under natural conditions, which will cause immeasurable damage to the environment. Recently, however, a research team in Japan discovered a new type of pet-eating bacteria-"Osaka Sakamoto".
"Sakamoto Osaka" was discovered by accident when a research team led by Hirofumi Oda of Kyoto University of Technology and Kenji Miyamoto of Keio University collected sediment samples contaminated by PET near a garbage collection facility in Sakai, Japan.
Sakamoto Osaka is of great significance to the degradation of PET plastics. Before this bacterium, no organism that can degrade PET as the main carbon source and energy source has been found. As a recycling and bioremediation method, the appearance of Sakamoto Osaka makes it possible to "biodegrade pets".
So how does Sakamoto Osaka digest pets?
There are two enzymes involved in the decomposition of PET in this bacterium.
In this way, PET will return to the original monomer, and bacteria will further decompose it, and finally return to the natural element cycle in the form of carbon dioxide and water, from which bacteria will obtain energy for survival.
Although bacteria decompose PET very slowly, scientists have found that after some genetic engineering modifications, the decomposition speed of bacteria can be doubled. At present, the National Renewable Energy Laboratory (NREL) of Portsmouth University in the United Kingdom is re-studying this fungus in Osaka. The research team used synchrotron to study the atomic structures of PET hydrolase and MHET hydrolase. With the help of synchrotron, the research team obtained the 3D structures of these two enzymes and their interactions. Subsequently, the research team physically connected the bacterial PET hydrolase and MHET hydrolase, which improved the efficiency of bacterial decomposition of PET by 6 times.
But there is still a long way to go before it is really put into practical use. What needs to be solved urgently now is how to realize mass production and how to apply it in the future. I believe that through the efforts of scientists and the application of genetic engineering in the future, we will definitely find a way to make PET decompose faster.
Write at the end:
Although the microorganisms and enzymes discovered this time can really help human beings solve the plastic pollution problem we face in the future, human beings should not regard it as the ultimate solution. The most scientific way to solve plastic pollution should be to reduce the use of plastics, scientifically coordinate the use of various materials in the future, and protect the global environment. This is our primary goal.
This article is the selected work of the first children's popular science essay contest in Zhengzhou.
Author: Jiang Dandan
Views only represent the author himself, not his position.