DNA-powered batteries, carbon-sinking microbes, and cholesterol-fighting coffee. This week’s coolest things find solutions to big problems hiding in small packages.
What is it? Marine biologists at the University of Technology Sydney have uncovered a previously unidentified source of carbon sequestration in the ocean: the loogies of a newly discovered microbe species.
Why does it matter? The findings change our understanding of how carbon is being naturally sequestered in the seas. “The implication is that there’s potentially more carbon sinking in the ocean than we currently think,” said Martina Doblin, senior author of a new study in Nature Communications. Moreover, it may be possible to cultivate the marine microbe and harness its carbon-sequestering prowess.
How does it work? The organism, Prorocentrum cf. balticum, is what’s known as a mixotrophic protist, which survives through a combination of photosynthesis and consuming other organisms. The key is in its method of predation. The microbe releases a carbon-rich exopolymer glob called a “mucosphere,” which entraps other microorganisms. Once the microbe has eaten its fill of the catch, it releases the mucosphere, which sinks, carrying its carbon as well as that of the unfortunate prey stuck within. “This could be a game changer in the way we think about carbon and the way it moves in the marine environment,” Doblin said.
What is it? Defense researchers in the UK developed a bio-battery that uses DNA and natural enzymes to provide energy.
Why does it matter? Scientists hope the technology will be safer for military personnel on the ground. Batteries now used by soldiers contain “a lot of energy in chemical format and if that battery gets shot, for example, it’s going to explode and burst into flames,” said Petra Oyston, a scientist with the Defence Science and Technology Laboratory, which is collaborating with the U.S. Department of Defense. If the bio-battery under development got shot, “it would just go splat,” she said.
How does it work? The DNA in the small, bullet-shaped battery acts as a scaffold for enzymes that degrade lactate — lactic acid — as it cascades by. That releases electrons, which are captured and used for power. The materials could be dried and reconstituted with water, making it highly portable. The technology could one day be used in innovative new formats such as tiny batteries too small to see or power-generating coatings.
What is it? Mechanical engineers at Johns Hopkins University created a highly shock-absorbing material that is as strong as metal and as light as plastic.
Why does it matter? The material could be used for more effective helmets and padding for athletes and for soldiers, or to make lightweight car bumpers. “The material offers more protection from a wide range of impacts, but being lighter could reduce fuel consumption and the environmental impact of vehicles while being more comfortable for protective gear wearers,” said Sung Hoon Kang, senior author on a new paper in Advanced Materials.
How does it work? The foam-like material harnesses the unique properties of liquid crystal elastomers (LCE), typically used in robotics, which have a rubbery elasticity that enables them to morph in response to force and return to their original shape. Kang’s team organized the LCEs in such a way that the more the material is deformed, the more shock it can absorb. Protective devices often cannot be reused after an impact, so the material could be a game changer for helmets, as well as car and aerospace parts.
Green Hydrogen, Hold The Bubbles
What is it? An efficient hydrogen electrolyzer invented by scientists at Australia’s University of Wollongong could help rapidly boost green hydrogen production in the next few years.
Why does it matter? Renewable hydrogen is crucial for decarbonizing highly polluting sectors such as steel. But the operation of the machines typically used to make hydrogen — called water electrolyzers — can still be expensive. Paul Barrett, CEO of Hysata, which is commercializing the new technology, said it will be cheaper than making hydrogen using fossil fuels.
How does it work? Electrolyzers use energy to break water into hydrogen and oxygen. In typical machines, the oxygen bubbles up through the water as it is split, while the hydrogen enters a gas chamber. Existing electrolyzers require about 47.5 kWh of electricity to produce 1 kilogram of hydrogen. The International Renewable Energy Agency (IRENA) has a goal to get below 42 kWh/kg by 2050. Hysata’s machines surpassed IRENA’s target, with energy consumption of just 40.4 kWh/kg, as described in Nature Communications. The electrolyzer achieved this high efficiency through bubble-free capillary-fed electrolysis. The capillary system draws water up from a lower reservoir and immediately diverts both gases produced into separate chambers.
What is it? Canadian researchers at the Research Institute of St. Joe’s Hamilton uncovered the biological link that may explain why caffeine drinkers appear to be less likely to die from cardiovascular disease.
Why does it matter? It has been shown that people who drink two to three cups of coffee per day have a lower risk of cardiovascular disease, but it was not understood how caffeine affects cardiovascular health. A new study in Nature Communications finds that caffeine interacts with a series of proteins that regulate LDL (or “bad”) cholesterol in the blood. “These findings have wide-ranging implications as they connect this widely consumed, biologically active compound to cholesterol metabolism at a molecular level,” said co-author Guillaume Paré.
How does it work? The researchers looked at caffeine’s effect on a protein called PCSK9, which lowers the liver’s ability to pull LDL cholesterol out of the blood. In previous work, they found that lower levels of PCSK9 led to reduced cholesterol levels. Here, they showed that caffeine blocks the activation of another protein (SREBP2) that encourages production of PCSK9. The caffeine thus halts a domino effect that would otherwise lead to a potentially unhealthy buildup of cholesterol. The team is developing more potent caffeine derivatives that they hope to use in new cholesterol-lowering medicines.