Amazon fungus is able to feed on "indestructible" plastic

Source: Microbiology (2000) 146:2079-2089    

Biodiversity in the Amazonian jungle could help find solutions to our modern-day problems.  Researchers have found microscopic fungus in the Amazon which can eat plastic in zero oxygen (anaerobic) conditions.  This means that plastics like polyurethanes which are prized for their durability (and which are virtually indestructible in the waste phase of life) could potentially be biodegraded by this fungus.

The research comes from the Department of Molecular Biophysics and Biochemistry, Yale University, who together with the Universidad Nacional San Antonio Abad del Cusco, Peru, reported that they had found fungi strains able to biodegrade polyester polyurethanes (PUR).

Polyurethanes are a type of plastic, man-made polymers used in a wide variety of products including in the medical, automotive and industrial fields.  These plastics can be recycled, but in most countries landfills still retain huge amounts that will persist for hundreds of years.  There’s also the legacy problem of many years of landfills containing plastics which do not biodegrade easily.

The work was part of the Yale’s annual Rainforest Expedition where students explored the rich resources of Ecuador’s jungles.  While investigating plants and the fungi found on them, they discovered species which might be able to help tackle a global waste problem.

Some work on biodegradation of polyurethane has been done in the past but most of the fungi and bacteria used to break them down have to be isolated from soil samples.  The novelty of the Yale work is that these fungi are endophytic (meaning that they live within a plant, often in a mutually-beneficial relationship) and are easily accessible.  One of the species, Pestalotiopsis microspora, was able to grow and survive on polyurethane and use it as its only carbon source in anaerobic conditions.  The research group isolated the enzyme responsible for this behaviour (serine hydrolase) and found that it is able to clear high concentrations of the polymer in under an hour.

Protecting the rainforest seems not only to be a solution for climate change problems, but also an incredible source of solutions for our modern days hazardous behaviours.

Post by Ana I. Catarino