The enzymes could enable plastic bottles to be fully recycled for the first time. Photograph: Fred Dufour/AFP/Getty Images
Scientists have created a mutant enzyme that breaks down plastic drinks bottles – by accident. The breakthrough could help solve the global plastic pollution crisis by enabling for the first time the full recycling of bottles.
The new research was spurred by the discovery in 2016 of the first bacterium that had naturally evolved to eat plastic, at a waste dump in Japan. Scientists have now revealed the detailed structure of the crucial enzyme produced by the bug.
The international team then tweaked the enzyme to see how it had evolved, but tests showed they had inadvertently made the molecule even better at breaking down the PET (polyethylene terephthalate) plastic used for soft drink bottles. “What actually turned out was we improved the enzyme, which was a bit of a shock,” said Prof John McGeehan, at the University of Portsmouth, UK, who led the research. “It’s great and a real finding.”
The mutant enzyme takes a few days to start breaking down the plastic – far faster than the centuries it takes in the oceans. But the researchers are optimistic this can be speeded up even further and become a viable large-scale process.
“What we are hoping to do is use this enzyme to turn this plastic back into its original components, so we can literally recycle it back to plastic,” said McGeehan. “It means we won’t need to dig up any more oil and, fundamentally, it should reduce the amount of plastic in the environment.”
About 1m plastic bottles are sold each minute around the globe and, with just 14% recycled, many end up in the oceans where they have polluted even the remotest parts, harming marine life and potentially people who eat seafood. “It is incredibly resistant to degradation. Some of those images are horrific,” said McGeehan. “It is one of these wonder materials that has been made a little bit too well.”
However, currently even those bottles that are recycled can only be turned into opaque fibres for clothing or carpets. The new enzyme indicates a way to recycle clear plastic bottles back into clear plastic bottles, which could slash the need to produce new plastic.
“You are always up against the fact that oil is cheap, so virgin PET is cheap,” said McGeehan. “It is so easy for manufacturers to generate more of that stuff, rather than even try to recycle. But I believe there is a public driver here: perception is changing so much that companies are starting to look at how they can properly recycle these.”
The new research, published in the journal Proceedings of the National Academy of Sciences, began by determining the precise structure of the enzyme produced by the Japanese bug. The team used the Diamond Light Source, near Oxford, UK, an intense beam of X-rays that is 10bn times brighter than the sun and can reveal individual atoms.
The structure of the enzyme looked very similar to one evolved by many bacteria to break down cutin, a natural polymer used as a protective coating by plants. But when the team manipulated the enzyme to explore this connection, they accidentally improved its ability to eat PET.
“It is a modest improvement – 20% better – but that is not the point,” said McGeehan. “It’s incredible because it tells us that the enzyme is not yet optimised. It gives us scope to use all the technology used in other enzyme development for years and years and make a super-fast enzyme.”
Industrial enzymes are widely used in, for example, washing powders and biofuel production, They have been made to work up to 1,000 times faster in a few years, the same timescale McGeehan envisages for the plastic-eating enzyme. A patent has been filed on the specific mutant enzyme by the Portsmouth researchers and those from the US National Renewable Energy Laboratory in Colorado.
One possible improvement being explored is to transplant the mutant enzyme into an “extremophile bacteria” that can survive temperatures above the 70C melting point of PET – the plastic is likely to degrade 10-100 times faster when molten.
Earlier work had shown that some fungi can break down PET plastic, which makes up about 20% of global plastic production. But bacteria are far easier to harness for industrial uses.
Other types of plastic could be broken down by bacteria currently evolving in the environment, McGeehan said: “People are now searching vigorously for those.” PET sinks in seawater but some scientists have conjectured that plastic-eating bugs might one day be sprayed on the huge plastic garbage patches in the oceans to clean them up.
“I think [the new research] is very exciting work, showing there is strong potential to use enzyme technology to help with society’s growing waste problem,” said Oliver Jones, a chemist at RMIT University in Melbourne, Australia, and not part of the research team.
“Enzymes are non-toxic, biodegradable and can be produced in large amounts by microorganisms,” he said. “There is still a way to go before you could recycle large amounts of plastic with enzymes, and reducing the amount of plastic produced in the first place might, perhaps, be preferable. [But] this is certainly a step in a positive direction.”
Prof Adisa Azapagic, at the University of Manchester in the UK, agreed the enzyme could be useful but added: “A full life-cycle assessment would be needed to ensure the technology does not solve one environmental problem – waste – at the expense of others, including additional greenhouse gas emissions.”
MORE EVIDENCE OF OBAMA'S TRAITOROUS ACTS TO BURY THIS COUNTRY ...................
(FLORIDA FEDERAL) COURT RULES ILLEGAL ALIENS CAN SUE OVER "DISCRIMINATORY EMPLOYMENT POLICY" REQUIRING GREEN CARDS
This shows how out of touch the Obama 'judges' are with the real world. An employer can be charged and fined for hiring individuals without green cards but the illegal aliens can sue the employers for not hiring them for not having a green card. Is there any doubt that this entire system is broken and needs to be replaced from the top down? You can thank the Bushes, Clintons and Obamas for that.
APRIL 11, 2018 JUDICIAL WATCH
For the second time in a few years, a federal courthas ruled that illegal immigrants can sue American employers that refuse to hire them because they require workers to be U.S. citizens or legal residents (green card holders).
The latest blow to the rule of law wasdelivered by an Obama-appointed federal judge in south Floridawho handed a powerful open-borders group a huge victory in a case accusing a major U.S. company of discriminating against an illegal immigrant.
Though years apart, both lawsuits were filed by the Mexican American Legal Defense and Educational Fund (MALDEF), a leftist group that specializes in discrimination lawsuits on behalf of illegal immigrants and has Chicago ties to Obama.
MALDEF pushes for free college tuition for illegal immigrants and lowering educational standards to accommodate new migrants. Its leadership refers to the U.S. government’s immigration enforcement effort as racist and xenophobic, and says it’s racist to make English the country’s official national language and inhumane to protect the southern border with a fence.
(TRY crossing the northern border in to Canada or the southern border in to Mexico and see what prison you wind up in and if you can successfully sue either country or even get a ticket back home in the states. The borders of the united States, however, are supposed to be open and 'free' to any one and any thing without question or legal actions to the unlawful invaders - quite the opposite to Mexico and Canada.)
Both MALDEF victories involve plaintiffs who benefit from a special Obama amnesty known as Deferred Action for Childhood Arrivals (DACA) that shields nearly 800,000 illegal aliens under the age of 31 from deportation.
In the recent Florida case a Venezuelan immigrant, David Rodriguez, living in Miami is suing consumer goods corporation Procter & Gamble for refusing to give him a paid internship because he is not a legal resident or citizen of the United States. MALDEF filed the lawsuit last year in U.S. District Court for the Southern District of Florida. Procter & Gamble requires citizenship and immigration status information on its applications and warns that candidates “must be a U.S. citizen or national, refugee, asylee or lawful permanent resident.” Rodriquez is neither and he quickly played the discrimination card after getting nixed as a candidate.
In a statement MALDEFF’s president reminds that “work-authorized DACA holders are valuable contributors to our economy” and “should not have to face arbitrary and biased exclusions from employment, especially by large and sophisticated corporations like Procter & Gamble.”
Judge Kathleen M. Williams, a former public defender appointed to the federal bench by Obama in 2011, agrees, citing MALDEF’s other lawsuit in her ruling. In denying Procter & Gamble’s motion to dismiss Rodriguez’s lawsuit, Judge Williams claims the Venezuelan immigrant’s claims are “strikingly similar” to those in MALDEF’s 2014 suit against insurance company Northwestern Mutual in New York. In that complaint, a Mexican illegal alien protected by DACA alleged that Northwestern Mutual’s policy requiring him to have a green card because he’s not a U.S. citizen discriminated against him. Requiring the Mexican national, Ruben Juarez, to provide proof of legal residency imposed an additional burden that constitutes alienage discrimination, according to the complaint filed on his behalf by MALDEF.
The federal judge hearing that case in New York agreed and, in a federal courtroom more than 1,000 miles south, Williams used the decision to justify hers. “In Juarez, the plaintiff was a DACA recipient who was denied employment based on Northwestern Mutual’s policy to only hire U.S. citizens and green card holders,” Judge Williams writes in her ruling. “There, on strikingly similar facts, the court found that Northwestern Mutual’s policy impermissibly discriminated against a subclass of Iawfully present aliens.” The ruling continues to say that Procter & Gamble’s policy could be construed to discriminate against a subset of legal aliens, which are protected. It seems to agree with the illegal alien’s assertions that Procter & Gamble has a “facially discriminatory employment policy” for requiring candidates to furnish proof that they’re in the U.S. legally.
Traitor Obama's policies continue to live on presenting serious legal problems for this nation long after his term as 'president' of the criminal cabal rogue 'government' has ended.
North and South Korea are in talks to announce a permanent end to the officially declared military conflict between the two countries, daily newspaper Munhwa Ilbo reported Tuesday, citing an unnamed South Korean official.
Ahead of a summit next week between North Korean premier Kim Jong Un and South Korean President Moon Jae-in, lawmakers from the neighboring states were thought to be negotiating the details of a joint statement that could outline an end to the confrontation.
Kim and Moon could also discuss returning the heavily fortified demilitarized zone separating them to its original state, the newspaper said.
Pyongyang and Seoul have technically been at war since the 1950-1953 Korean conflict ended with a truce — and not a peace treaty. Geopolitical tensions have occasionally flared up since the armistice, although to date both countries have managed to avoid another devastating conflict.
A successful summit between the Koreas later this month could help pave the way for a meeting between Kim and President Donald Trump. The U.S. president and North Korean leader are poised to hold talks in late May or June, according to the Korean Central News Agency (KCNA).
