Photo/IllutrationIdeonella sakaiensis, a plastic-eating bacterium (Provided by Shosuke Yoshida of the Nara Institute of Science and Technology)

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A bacterium that gorges on PET bottles has spurred a global research race to harness its powers in the battle against plastics pollution in the world's oceans.

The bacterium was given the name Ideonella sakaiensis in 2005, as it was found in soil samples at a plastic bottle processing plant in Sakai, Osaka Prefecture.

Methods for dealing with the contamination of marine environments by plastics is expected to be a major theme of the Group of 20 summit to be held in Osaka on June 28-29.

Kohei Oda, now professor emeritus of applied biology at the Kyoto Institute of Technology, was among those who were part of a team that discovered the bacterium.

Subsequent research by Shosuke Yoshida, now a specially appointed associate professor of environmental microbiology at the Nara Institute of Science and Technology, found that the bacterium used two enzymes to decompose polyethylene terephthalate (PET), a synthetic resin widely used in plastic products.

The bacterium was found to consume PET film with a thickness of 0.2 millimeter in about a month while decomposing it into carbon dioxide and water.

PET was long believed not to be biodegradable, as it is produced using petroleum.

But when Oda and others released an article in an academic journal in 2016 about how Ideonella sakaiensis feeds on plastic bottles, the global scientific community was stunned.

Inquiries came in from fiber and other manufacturing companies around the world, and a race to uncover how the enzymes break down PET was also triggered.

In 2017, a team of Chinese scientists released its finding of the analysis of the structure of one of the enyzmes, dubbed PETase, and published it in a British journal.

That was followed by other articles by South Korean and Chilean teams that provided greater detail into the enzyme structure.

A British team succeeded in improving the ability of the enzyme to decompose plastic, leading the BBC to report that the finding could set off a revolution in PET bottle recycling and more effective reuse of plastics.

This year, a German team succeeded in creating a 3-D analysis of the other enzyme, MHETase.

Yoshida and other scientists have joined the international effort to determine what conditions allow the enzymes to break down plastics in a more efficient manner.

"Although I believe it will take time, I am hopeful that the bacterium found in Sakai will become the catalyst for a resolution of the plastic problem," Oda said.