Could a new plastic-eating bacteria helpcombat this pollution scourge?

A team of Japanese scientists has found a species of bacteria that eats the type of plastic found in most disposable

water bottles. Photo: Anacleto Rapping/Los Angeles Times/TNS

Nature has begun to fight back against the vast piles of filth dumped into its soils, rivers

and oceans by evolving a plastic-eating bacteria – the first known to science.

In a report published in the journal Science, a team of Japanese researchers described a

species of bacteria that can break the molecular bonds of one of the world’s most-used

plastics - polyethylene terephthalate, also known as PET or polyester.

The Japanese research team sifted through hundreds of samples of PET pollution before

finding a colony of organisms using the plastic as a food source.

Further tests found the bacteria almost completely degraded low-quality plastic within six

weeks. This was voracious when compared to other biological agents; including a related

bacteria, leaf compost and a fungus enzyme recently found to have an appetite for PET.

“This is the first rigorous study – it appears to be very carefully done – that I have seen that

shows plastic being hydrolyzed (broken down) by bacteria,” said Dr Tracy Mincer, a

researcher at Woods Hole Oceanographic Institution.

By Karl Mathiesen, The Guardian on 03.18.16

Word Count 904

This article is available at 5 reading levels at https://newsela.com. 1

The molecules that form PET are bonded very strongly, said professor Uwe Bornscheuer in

an accompanying comment piece in Science. “Until recently, no organisms were known to

be able to decompose it.”

In a Gaian twist, initial genetic examination revealed the bacteria, named Ideonella

sakaiensis 201-F6, may have evolved enzymes specifically capable of breaking down PET

in response to the accumulation of the plastic in the environment in the past 70 years.

Such rapid evolution was possible, said Enzo Palombo, a professor of microbiology at

Swinburne University, given that microbes have an extraordinary ability to adapt to their

surroundings. “If you put a bacteria in a situation where they’ve only got one food source to

consume, over time they will adapt to do that,” he said.

“I think we are seeing how nature can surprise us and in the end the resiliency of nature

itself,” added Mincer.

The bacteria took longer to eat away highly crystallised PET, which is used in plastic

bottles. That means the enzymes and processes would need refinement before they could

be useful for industrial recycling or pollution clean-up.

“It’s difficult to break down highly crystallised PET,” said professor Kenji Miyamoto from

Keio University, one of the authors of the study. “Our research results are just the initiation

for the application. We have to work on so many issues needed for various applications. It

takes a long time,” he said.

A third of all plastics end up in the environment and 8m tonnes end up in the ocean every

year, creating vast accumulations of life-choking rubbish.

PET makes up almost one-sixth of the world’s annual plastic production of 311m tons.

Despite PET being one of the more commonly recycled plastics, the World Economic

Forum (WEF) reports that only just over half is ever collected for recycling and far less

actually ends up being reused.

Advances in biodegradable plastics and recycling offer hope for the future, said

Bornscheuer, “but (this) does not help to get rid of the plastics already in the environment”.

However the potential applications of the discovery remain unclear. The most obvious use

would be as a biological agent in nature, said Palombo. Bacteria could be sprayed on the

huge floating trash heaps building up in the oceans. This method is most notably

employed to combat oil spills.

This particular bacteria would not be useful for this process as it only consumes PET,

which is too dense to float on water. But Bornscheuer said the discovery could open the

door to the discovery or manufacture of biological agents able to break down other

plastics.

Palombo said the discovery suggested that other bacteria may have already evolved to do

this job and simply needed to be found.

This article is available at 5 reading levels at https://newsela.com. 2

“I would not be surprised if samples of ocean plastics contained microbes that are happily

growing on this material and could be isolated in the same manner,” he said.

But Mincer said breaking down ocean rubbish came with dangers of its own. Plastics often

contain additives that can be toxic when released. WEF estimates that the 150m tonnes of

plastic currently in the ocean contain roughly 23m tonnes of additives.

“Plastic debris may have been less toxic in the whole unhydrolyzed form where it would

ultimately have been buried in the sediments on a geological timescale,” said Mincer.

Beyond dealing with the plastic already fouling up the environment, the bacteria could

potentially be used in industrial recycling processes.

“Certainly, the use of these microbes or enzymes could play a role in remediation of plastic

in a controlled reactor,” said Mincer.

Miyamoto’s team suggested that the environmentally benign constituents left behind by the

bacteria could be the same ones from which the plastic is formed. If this were true and a

process could be developed to isolate them, Bornscheuer said: “This could provide huge

savings in the production of new polymer without the need for petrol-based starting

materials.” According to the WEF, 6 percent of global oil production is devoted to the

production of plastics.

But the plastics industry said the potential for a new biological process to replace or

augment the current mechanical recycling process was very small.

“PET is 100 percent recyclable,” said Mike Neal, the chairman of the Committee of PET

Manufacturers in Europe. “I expect that a biodegradation system would require a similar

engineering process to chemical depolymerisation and as such is unlikely to be

economically viable,” he said.

This article is available at 5 reading levels at https://newsela.com. 3

Quiz

1 Which of the following answer options accurately represents the relationship between the

article's central ideas?

(A) A new bacteria has been discovered that breaks down certain types of

plastic, giving hope to researchers for future discoveries that can help with

pollution.

(B) Plastics are a major pollutant in our environment. There are many different

solutions being tested, such as biodegradable plastics, advances in

recycling, and biological processes.

(C) A new bacteria has been discovered that eats through plastic and can help

solve the crisis with ocean waste, just like a similar bacteria has been used

to handle oil spills.

(D) Scientists are amazed that bacteria can change as quickly as it appears to

have done. If bacteria is left alone with a food source, it can develop new

enzymes. This gives researchers hope for our environment.

2 Which paragraph would be MOST important to include in a summary of this article?

(A) In a Gaian twist, initial genetic examination revealed the bacteria, named

Ideonella sakaiensis 201-F6, may have evolved enzymes specifically

capable of breaking down PET in response to the accumulation of the

plastic in the environment in the past 70 years.

(B) But Mincer said breaking down ocean rubbish came with dangers of its own.

Plastics often contain additives that can be toxic when released. WEF

estimates that the 150m tonnes of plastic currently in the ocean contain

roughly 23m tonnes of additives.

(C) Miyamoto’s team suggested that the environmentally benign constituents left

behind by the bacteria could be the same ones from which the plastic is

formed. If this were true and a process could be developed to isolate them,

Bornscheuer said: “This could provide huge savings in the production of

new polymer without the need for petrol-based starting materials.”

According to the WEF, 6 percent of global oil production is devoted to the

production of plastics.

(D) “PET is 100 percent recyclable,” said Mike Neal, the chairman of the

Committee of PET Manufacturers in Europe. “I expect that a biodegradation

system would require a similar engineering process to chemical

depolymerisation and as such is unlikely to be economically viable,” he said.

This article is available at 5 reading levels at https://newsela.com. 4

3 According to the article, all of the following are true about the new bacteria discovery EXCEPT:

(A) It appears to be the first study that showed plastic being quickly broken

down by bacteria.

(B) After more experimentation and development, the new bacteria will be able

to help break down ocean plastics.

(C) There is hope for the potential of this bacteria or other bacteria to help break

down plastics, but there is also concern about releasing toxins.

(D) Scientists believe the bacteria may have developed enzymes capable of

breaking down plastics in response to plastics in the environment.

4 Why is Mike Neal not as excited as the scientists about the potential of the bacteria in helping

with the production and recycling of plastics?

(A) He thinks it could lead to an inferior type of plastic.

(B) He thinks that it is a promising idea, but it's just not ready yet.

(C) He thinks a new process would require too much money for the benefit.

(D) He thinks the way that the process would be much too complicated.

This article is available at 5 reading levels at https://newsela.com. 5

Answer Key

1 Which of the following answer options accurately represents the relationship between the

article's central ideas?

(A) A new bacteria has been discovered that breaks down certain types of

plastic, giving hope to researchers for future discoveries that can help

with pollution.

(B) Plastics are a major pollutant in our environment. There are many different

solutions being tested, such as biodegradable plastics, advances in

recycling, and biological processes.

(C) A new bacteria has been discovered that eats through plastic and can help

solve the crisis with ocean waste, just like a similar bacteria has been used

to handle oil spills.

(D) Scientists are amazed that bacteria can change as quickly as it appears to

have done. If bacteria is left alone with a food source, it can develop new

enzymes. This gives researchers hope for our environment.

2 Which paragraph would be MOST important to include in a summary of this article?

(A) In a Gaian twist, initial genetic examination revealed the bacteria,

named Ideonella sakaiensis 201-F6, may have evolved enzymes

specifically capable of breaking down PET in response to the

accumulation of the plastic in the environment in the past 70 years.

(B) But Mincer said breaking down ocean rubbish came with dangers of its own.

Plastics often contain additives that can be toxic when released. WEF

estimates that the 150m tonnes of plastic currently in the ocean contain

roughly 23m tonnes of additives.

(C) Miyamoto’s team suggested that the environmentally benign constituents left

behind by the bacteria could be the same ones from which the plastic is

formed. If this were true and a process could be developed to isolate them,

Bornscheuer said: “This could provide huge savings in the production of

new polymer without the need for petrol-based starting materials.”

According to the WEF, 6 percent of global oil production is devoted to the

production of plastics.

(D) “PET is 100 percent recyclable,” said Mike Neal, the chairman of the

Committee of PET Manufacturers in Europe. “I expect that a biodegradation

system would require a similar engineering process to chemical

depolymerisation and as such is unlikely to be economically viable,” he said.

This article is available at 5 reading levels at https://newsela.com. 6

3 According to the article, all of the following are true about the new bacteria discovery EXCEPT:

(A) It appears to be the first study that showed plastic being quickly broken

down by bacteria.

(B) After more experimentation and development, the new bacteria will be

able to help break down ocean plastics.

(C) There is hope for the potential of this bacteria or other bacteria to help break

down plastics, but there is also concern about releasing toxins.

(D) Scientists believe the bacteria may have developed enzymes capable of

breaking down plastics in response to plastics in the environment.

4 Why is Mike Neal not as excited as the scientists about the potential of the bacteria in helping

with the production and recycling of plastics?

(A) He thinks it could lead to an inferior type of plastic.

(B) He thinks that it is a promising idea, but it's just not ready yet.

(C) He thinks a new process would require too much money for the benefit.

(D) He thinks the way that the process would be much too complicated.

This article is available at 5 reading levels at https://newsela.com. 7