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Scientists are turning to unusual places to find new compounds to fight off drug-resistant “superbugs.” The discovery came from milking ferocious mammals!

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Tasmanian Devil Milk:

CO2 to ethanol:
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A huge milestone in medicine was the discovery of antibiotics in the early 1900s, arming doctors against bacterial infections like never before. But the thing about bacteria is they reproduce really quickly, which means more genetic mutations, and the chance of developing resistance to our drugs. In fact, MRSA is a strain of bacteria that runs rampant in hospitals nowadays because of its resistance to lots of antibiotics. So scientists are turning to unusual places to find new compounds to fight off these drug-resistant “superbugs.” Including... Tasmanian devil milk.

In a paper published this month, researchers at the University of Sydney reported that this marsupial’s milk is full of antimicrobial compounds called cathelicidins. These compounds have been found in mammals and birds, and they basically work by poking holes in the cell membrane of a bacterium or fungus, which kills them.

So far, we know that humans have one cathelicidin protein, but Tasmanian devils have six of them, which these scientists named Saha-CATH1 through 6. And they’re really important in developing the immune system of newborn Tasmanian devil joeys, which initially don’t have any protection from all the microbes in their mom’s pouch. So the researchers synthesized those six cathelicidins and pitted them against 25 strains of bacteria and 6 strains of fungi.

Three of the compounds didn’t show any antimicrobial properties, so they might be involved in regulating other parts of the Tasmanian devil immune system. But Saha-CATH3, 5, and 6 did. Saha-CATH3 was specifically out to kill one strain of fungus. On the other hand, Saha-CATH6 killed several strains of Streptococcus bacteria and a strain of antibiotic-resistant bacteria called VREF. And Saha-CATH5 seems to be the most promising compound when it comes to potential drug development, since it wiped out just over half of the bacteria and fungi that were tested, including the superbugs VREF and MRSA.

So there’s a lot we can learn from other animals when it comes to human medicine, especially in our never-ending battle against bacteria. But not all scientists make discoveries by milking ferocious mammals. Another unexpected find this month happened at a chemistry lab bench in the U.S. Department of Energy’s Oak Ridge National Laboratory. It’s been getting a lot of press, because people hope this discovery could help control carbon dioxide levels in the Earth’s atmosphere, by turning the gas into a liquid fuel: ethanol.

You’ve probably heard time and again that carbon dioxide is made from burning fossil fuels, and it’s one of the heat-trapping greenhouse gases that has a huge effect on global climate. These researchers were working a nanotechnology-based catalyst to try and convert CO2 into a different hydrocarbon, like methane gas. They used carbon and nitrogen atoms to make a structure full of pointy nanospikes, each about 50 nanometers tall. Then they took copper nanoparticles, which are really tiny and made of just hundreds of atoms, and sprinkled them on the spikes.

Copper is highly conductive, so it acts as a great catalyst to help shuffle around electrons and speed up certain chemical reactions. When a current of electricity is run through this nanostructure, the copper nanoparticles help concentrate it at the tip of the carbon nanospikes, kind of like teeny tiny lightning rods. So when the scientists dissolved carbon dioxide in water and used this nanotechnology, all those concentrated electrons, plus the shape of those spikes, helped catalyze a reduction reaction.

Basically, this means the carbon dioxide molecules lose oxygen atoms and gain hydrogen atoms, to form chemicals like carbon monoxide. Then, the carbon monoxide molecules can bind together to make two-carbon structures, which get reduced again to form ethanol. The scientists described it as a sort of reverse chemical combustion reaction, since they started with a waste product and ended up with fuel.

Other researchers have made methane gas, from CO2 before, which is also used as fuel. But it’s harder to make a liquid fuel like ethanol, without getting a bunch of other byproducts. Thanks to this nanostructure though, these chemists had a pretty high yield: about 63% of the electrons from the current, and about 84% of the carbon dioxide molecules were turned into new ethanol molecules.

There seems to be a lot of potential for this technology on a bigger, industrial scale, especially because it uses pretty common materials: carbon, nitrogen, and copper. But there’s still a ton of research that needs to be done before that can happen, since it’s not that energy-efficient right now. In other words, they need to put a relatively high amount of energy into the reaction to make it work.

And even then, this process won’t necessarily reduce the amount of carbon dioxide in the atmosphere, because if we burn the ethanol, we’ll just be converting it back into CO2. Instead, it might help level off rising carbon dioxide levels, so we don’t have to keep making and burning as much fuel from other sources.

So it’s probably not a miraculous solution to climate change, just like Tasmanian devil milk proteins won’t help us kill all deadly bacteria. But scientific research is all about taking little steps towards bigger breakthroughs, which includes these unexpected discoveries.

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