065: Plastic-eating Bacteria to the Rescue

Plastic-eating Bacteria to the Rescue?

Chris: [Ladies and gentlemen, we are at war! I’m not talking about a war on terror, a rogue state or even drugs, I’m talking about something much closer to home. I’m talking about plastic. Plasti-phobia is very popular at the moment; in the last week alone the UK government have announced a policy to ban the use of plastic straws in pubs, clubs and restaurants as the national still reels from the images shown in the stunning Blue Planet 2 series. And right here on Blue Streak Science we spoke a couple of weeks about a giant island of plastic adrift on the ocean, spreading micro-plastics far and wide and into the food chain.

The reason that this war on plastic is so hard to win is that, despite these increasingly apparent environmental impacts, we just can’t quit it. It’s a bit like a guilty affair; we know that it’s reckless, irresponsible and hurts others but it’s just so convenient and easy. Especially for us in the world of science and laboratories; with our disposable pipettes tips, Petri dishes, deep well plates and culture loops. We’ve been as much a part of the problem as we have the solution.

Up until now that is. The biggest problem that plastic presents is also its greatest asset; its resistance to biodegradation. But this resistance is starting to be ground down. In 2011 a single-celled fungus called pest-alo-tiopsis microspora was discovered which can digest polyurethane and in 2016 a strain of Ideonella Sakaiensis bacteria was identified that eats PET.

This bacteria was found outside a plastic recycling plant in Japan. What amazes me about this is just how quickly these organisms have evolved to exploit this new food source. We talk about antibiotic resistance as being a fast process but antibiotics are, for the most part, still going strong 100 years after their discovery. Plastics have been with us for half of that time and we’re already seeing this shift in our microflora.

So how are scientists helping with this? Well, if you give scientists the novel enzyme that is responsible for the breakdown of PET (rather imaginatively called. PETase, we don’t mess around with naming here. We call a spade a digging tool and a rose by any other name would be Rosa kordesii and it would not smell so sweet as the cross breed known as Louise Odier because science is complicated enough without adding a bunch of artsy-fartsy names to the mix that don’t mean anything).

But I digress; if you give scientists a novel enzyme (like PETase) then they will do what scientists do and dick around with it. Prof. John McGeeham and Dr. Gregg Beckham of the university of Portsmouth and NREL, respectively, have managed to not only make PETase more efficient but have also widened the range of plastics that it works on.

They didn’t initially set out to tweak the enzyme in this way; they were merely attempting to look at its crystal structure. Knowing this would allow the enzyme to be synthesised in the same way as ones that are already being used in your laundry detergent. It was during this synthesis that the error was made, resulting in a more efficient enzyme that can now be produced to aid the plastic recycling process.

Where will this take us in future years? With the microbial world churning on, who knows, maybe one day plastic will end up being no more durable than cardboard. We’ve certainly left enough of it around for the bugs to practice on!]

The Guardian, Science News, PNAS

“Warm Transplants” Save Livers and Lives

Nevena: [Few months ago we spoke of artificial womb and how the first lamb which was carried to term in one was the proof of concept that we might be well on the way to assisted pregnancies, when for health reasons the mother might not be able to carry the fetus to the end of the necessary period.

This story, published in Nature, is about slightly different type of womb-like device. One that can help transplantation organs to reach the patient in better condition and increase the chance of the transplantation procedure being successful.

There are many hurdles to a successful transplantation of organs - often times the storage of the organ between the donor and the recipient ends up damaging the organ to an extend which increases the risk of it failing and being rejected by the patient.

Now a new device which has been tested in the randomized clinical trial described in the nature paper authored by Dr David Nasralla and his colleagues, was shown to increase the success rate of liver transplantations.

One of the main differences with previous storage devices is that in keeps the organ at 37 degrees C (the body temperature of a healthy human). So far, transplant organs are always kept on ice (4 degrees C). While there are many rational reasons keeping on ice organs taken out of the body of donors makes sense, it might actually not be the most optimal way to do it.

Putting tissues and organ on ice for example can reduce the development of bacterial contaminations, it also is thought to induce the cellular chaperones - types of proteins which have the sole purpose of protecting the cells against stress (and if removing organ from its place is not stress, I don’t know what is). But it might appear that at least in the case of liver, putting it on ice it might damage the organ more than protect it.

The machine that was developed to try and remedy this actually supplies the liver with blood saturated with oxygen - lack of oxygen is one of the main reasons that tissues and cells fail. It also filters out immunogenic cells so as little as possible risk there is for immune response in the receiver of the organ and rejection. Additionally, the machine is equipped with a bunch of sensors which measure the performance of the organ and if by any chance, for whatever reason, it starts under performing before the procedure has taken place, the doctors can decide based on this information whether or not they should discard the liver or if it is safe to proceed with the transplantation.

At this point the downside of the machine is its price - soaring to as much as 8000 euros, this is virtually unachievable tag for most patients and it can hardly be covered by national health insurance programs.

But like all other tech, the hope is that the price tag will quickly start showing lower numbers as ways are established to use more sustainable and cheaper materials without sacrificing the performance of the machine. ]

Nature, Nature (original abstract)

Ibuprofen and acetaminophen (paracetamol) reduce dental pain more effectively than opioids

Chris: [Elvis Presley, Prince, Hank Williams, Heath Ledger, Sigmund Freud; these are just a few examples of high profile people who we have lost as a result of opioid abuse. These tragedies occur because these highly addictive substances are available, legally, as they are such effective painkillers; but a new study has concluded that they are not as effective as their less dangerous alternatives, ibruprofen and paracetamol. Could it be that these celebrities’ lives could have been saved if we had known this earlier? Well, only if they had been suffering from toothache.

This unexpected discovery comes after a wide literature review. Anita Aminoshariae is one of the study’s authors and explained that the aim was to create a compendium detailing both the benefits and harms of these medications as a resource for dentists to use in their clinical decision-making, and this resources says, don’t get your patients high!

Considering the consequences that opioid use can have, it is somewhat less surprising to find that the use of ibruprofen (either with or without paracetamol to assist) produces less adverse side effects as well as being more effective at managing the pain.

The reason why opioids are such a big problem is that they a part of the same family of chemicals as endorphins and dopamine that our bodies naturally create anyway. Medicinally, this is great because they can act on the brainstem and spinal cord like an endorphin (but much more powerfully) where they can suppress pain. The downside of this that it also affects the limbic system. If you have heard of endorphins or dopamine before then you’ve probably heard that they are the thing that makes us feel good; like chemical happiness. On the face of it, this may not seem like a bad side effect, to feel happy and relaxed about everything but the consequences are all too real.

It has been said that humanity only ever suffers from one addiction, opioids. Everything that we get addicted to, be it gambling, alcohol, sex, chocolate or building spreadsheets (maybe that’s just me) these things all prompt our body to make these chemicals. All these other addictions are just the lengths that we go to to feed our opioid habit. The problem with these medicinal opioids is that you cut out the middle man and just provide the brain with an artificial alternative much more potent than anything than your body can make. Just think about it; once you’ve got used to the experience of an opioid high, a genuine, natural feeling of euphoria would just feel lacklustre.

Ibruprofen, on the other hand, is an anti-inflammatory drug. Swelling is a normal response of the body to trauma but it can also be painful. Whilst the swelling is functional and can aid the healing process, it is possible to use these drugs to reduce the swelling and relieve the discomfort. Their effectiveness can be further improved by combining them with paracetamol. Also known as acetaminophen, it may come as a bit of a shock that no one actually knows exactly how it works. The leading theory is that it blocks the brain’s ability to detect prostaglandins which are a bit like anti-opioids; they make us feel pain rather than elation. This is the same chemical that causes swelling, so ibruprofen inhibits its production and then the paracetamol limits the brains ability to pick up on what’s left.

Maybe this is why this result has been discovered. There are no nerves within teeth themselves, but they are attached to some. Dental pain is often associated with swelling and pressure on these nerves. Whilst opioids will dull this pain and make you feel a bit better about it, ibruprofen will actually do something to ease the source of the pain. But not the pain in your soul; for that that I’m afraid that you’ll just have to stick with opioids and all of the risks that they entail.]

ScienceBlog, Case Western, Sci-News

TESS in the search of exoplanets

Nevena: [It seems like yesterday when the SpaceX’s Falcon Heavy rocket blasted Elon’s red Tesla roadster into space, but in the meantime the Falcon 9 (it’s smaller buddy) is busy with to serious space business delivering payloads into Earth’s orbit and beyond for various private and public programs.

It most recently brought to space a NASA probe which will search for exoplanets. The Transiting Exoplanet Survey Satellite or for short TESS is expected to deploy its solar panels as we speak and to start performing a number of internal checks before it starts collecting data.

Unlike other satellites before it, TESS will orbit Earth on a never used before orbit with a complex geometry, making two orbits around us for each orbit the Moon does. While this might seem a very random orbit to choose, surely you don’t think NASA didn’t choose it very carefully! The trick with this orbit is that it’s very stable - if for some reason the satellite goes slightly out of its way, the moon’s gravity will pull it back in place and allow it to keep doing it’s thing without having to do much maneuvering itself - talk about being sustainable in space. Also, in this orbit there’s much less space junk - something we unfortunately we have plenty of (and the cleaning of which Sophie talked about in our previous episode - go have a listen if you haven’t yet!).

Once in its place, the expectation for TESS are soaring - its equipment is building up on the Kepler telescope’s sensors and the hope is that it will discover even more exoplanets than Kepler ever could. Whatever TESS discovers, it will feed into the science that the James Webb telescope is expected to perform once it’s launched in 2020 and it reaches its sweet spot in space - the Lagrange point where the gravity of Earth and the Sun balance out so it can stay there and observe the deep space with the most powerful sensors we have ever made for space exploration. ]

Space.com, LA Times, Science News

A**hole of the Month

JD: The Blue Streak Science A**hole of the Month is governor Rick Snyder of the state of Michigan.

Let’s go back a few years to 2014 to Flint, Michigan.

That’s when officials, in order to save money, switched the city’s water source from Lake Huron to the Flint River.

Unfortunately, water from the river is 19 times more corrosive than that from the lake, according to researchers at Virginia Tech University.

That sounds bad, but in and of itself it really isn’t, unless you’re piping that water through antiquated pipes.

And it didn’t take long for the water started to look, smell and taste bad.

The more corrosive Flint River water caused lead to leach from pipes into the city's drinking water.

The immediate result was people getting rashes and hair loss from the lead in their water.

The long-term effects are well-known and far more dire, especially for children.

So the federal Environmental Protection Agency, the EPA, had to intervene.

Also, a class-action lawsuit followed against the state’s Department of Environmental Quality alleging that they failed to properly treat the water before it was pumped through the city’s old pipes.

Since that time it has been a mess in Flint.

Children with astronomically high levels of lead in their blood.

Residents forced to use bottled water for virtually everything.

Stop for a moment, and imagine what it would be like for you to shut off your taps, all of them, and rely on water that you have to drive somewhere and physically pick up.

Your drinking, cooking, bathing and showering, brushing your teeth, and even watering your garden.

All of it. Water you had to schlep from a distribution center to your home.

But thankfully that water was being paid for by the state of Michigan.

Until now.

Last week the Michigan government announced it would no longer provide free bottled water to residents of Flint four years into this public health debacle.

The closure of the state-funded water distribution centers, or free PODs, happened abruptly and surprised Flint Mayor Karen Weaver.

At a press conference this week she recalled her conversation with the governor, “When we talked about the PODs, the governor said we need to get over it. He said the water is testing well and we need to move on,”

Incidentally, is it any surprise that Flint, Michigan is majority African American and has a median household income of about $28,000?

Do you think this would be allowed to happen in West Palm Beach or Aspen, Colorado?

Flint still has about 12,000 homes with tainted lead service lines that need replacing.

Mayor Weaver stated, “They gave us their word that they would see us through this lead and galvanized service line replacement and that we would have PODs stay open until then, and they backed out on what they said,”

According to ReWire News, locals are taking matters into their own hands as the Snyder administration once again turns its back to the plight of Flint.

Local celebrities and organizations like Michigan Citizens for Water Conservation are fighting for water rights and advocating change; a young activist called Mari Copeny, started an online campaign that has raised more than $22,500 in seven days.

Flint officials are threatening to sue the state, and so are residents looking for continued bottled water distribution.

I don’t blame them.

And for turning your back on the good citizens of Flint, Michigan...governor Rick Snyder, you are the Blue Streak Science A**shole of the Month!

JD: Until next time...follow the science!