The Washington Post on scientists who “discovered that bacteria commonly found in wastewater can break down plastic to turn it into a food source, a finding that researchers hope could be a promising answer to combat one of Earth’s major pollution problems.”
In a study published Thursday in Environmental Science and Technology, scientists laid out their examination of Comamonas testosteroni, a bacteria that grows on polyethylene terephthalate, or PET, a plastic commonly found in single-use food packaging and water bottles. PET makes up about 12 percent of global solid waste and 90 million tons of the plastic produced each year… Unlike most other bacteria, which thrive on sugar, C. testosteroni has a more refined palate, including chemically complex materials from plants and plastics that take longer to decompose.
The researchers are the first to demonstrate not only that this bacteria can break down plastic, but they also illuminate exactly how they do it. Through six meticulous steps, involving complex imaging and gene editing techniques, the authors found that the bacteria first physically break down plastic by chewing it into smaller pieces. Then, they release enzymes — components of a cell that speed up chemical reactions — to chemically break down the plastic into a carbon-rich food source known as terephthalate…
The bacteria take a few months to break down chunks of plastic, according to Rebecca Wilkes [a lead author on the study and postdoctoral researcher at the National Renewable Energy Laboratory]. As a result, if the bacteria are going to be efficient tools, a lot of optimization needs to take place to speed up the rate at which they decompose pollutants. One approach is to promote bacterial growth by providing them with an additional food source, such as a chemical known as acetate.
A senior author on the study (and associate professor of civil and environmental engineering at Northwestern University) tells the Washington Post that “The machinery in environmental microbes is still a largely untapped potential for uncovering sustainable solutions we can exploit.”