Researchers identify a complex that hands mimivirus control of protein synthesis in infected amoebae
Category: futurism
Molecular ‘knitting machine’ for bacterial capsules mapped in 3D
Most bacteria, including many bacterial pathogens, are surrounded by an outer protective layer of sugar molecules, known as a capsule. This primarily protects the bacteria from environmental influences, but also serves as a kind of cloak of invisibility, enabling them to evade the phagocytes of our immune system. Structural biologists at the Helmholtz Center for Infection Research (HZI) have now used cryo-electron microscopy to visualize the central Wza-Wzc protein complex, with which sugar molecules pass from the interior of the bacterial cell to the outside, in three dimensions at the atomic level for the first time.
Their investigations also show how the channel is formed and which molecular players are involved in the active transport of sugar molecules through the channel. The researchers hope that their study will help identify target structures for potential drugs that could inhibit or completely prevent the formation of the bacterial capsule in the future. This would also make such bacterial pathogens vulnerable to attack by the immune system.
The study was conducted in collaboration with researchers from the Center for Structural Systems Biology (CSSB) in Hamburg and has now been published in the journal Nature Communications.
Scientists confirm one-dimensional electron behavior in phosphorus chains
For the first time, researchers have shown that self-assembled phosphorus chains can host genuinely one-dimensional electron behavior. Using advanced imaging and spectroscopy techniques, they separated the signals from chains aligned in different directions to reveal their true nature. The findings suggest that squeezing the chains closer together could trigger a dramatic shift from semiconductor to metal. That means simply adjusting density could unlock entirely new electronic states.
Antarctica sits above Earth’s strongest ‘gravity hole.’ Now we know how it got that way
Gravity feels reliable—stable and consistent enough to count on. But reality is far stranger than our intuition. In truth, the strength of gravity varies over Earth’s surface. And it is weakest beneath the frozen continent of Antarctica after accounting for Earth’s rotation.
A new study reveals how achingly slow rock movements deep under Earth’s surface over tens of millions of years led to today’s Antarctic gravity hole. The study highlights that the timing of changes in the Antarctic gravity low overlaps with major changes in Antarctica’s climate, and future research could reveal how the shifting gravity might have encouraged the growth of the frozen continent’s climate-defining ice sheets.
“If we can better understand how Earth’s interior shapes gravity and sea levels, we gain insight into factors that may matter for the growth and stability of large ice sheets,” said Alessandro Forte, Ph.D., a professor of geophysics at the University of Florida and co-author of the new study recreating the Antarctic gravity hole’s past.