Dog coronavirus jumps to humans, with a protein shift

N-terminus: The end of a peptide or protein primary structure in which the amino acid residue is not part of a peptide bond. The terminal group is often (but not always) an amine or ammonium cation.
Image Credit: Courtesy of Cornell University

Scientific Frontline: "At a Glance" Summary: Zoonotic Spillover of Canine Coronavirus

• Main Discovery: Researchers discovered a molecular shift in the N-terminus of the canine coronavirus spike protein, specifically the loss of the O-domain, which transforms the virus from a gastrointestinal and respiratory pathogen in animals to an exclusively respiratory pathogen in humans.
• Methodology: Scientists utilized advanced molecular evolution tools to evaluate natural selection pressures on the virus, comparing the genetic sequence of the canine coronavirus to related strains to identify the specific loss of the sialic acid-binding O-domain.
• Key Data: The modified canine coronavirus was initially identified in two Malaysian human patients with pneumonia between 2017 and 2018, and a similar variant was detected in Haiti in 2021, potentially marking it as the eighth known human coronavirus.
• Significance: The findings reveal a repeating evolutionary pattern of relaxed selection where coronaviruses lose their gastrointestinal binding capabilities to successfully jump to alternative hosts and establish respiratory infections.
• Future Application: Recognizing this tropism shift provides a critical framework for researchers to monitor the N-terminus domain of spike proteins, including in SARS-CoV-2, to predict, track, and potentially neutralize future zoonotic spillovers.
• Branch of Science: Virology, Evolutionary Biology, Veterinary Medicine
• Additional Detail: While the primary receptor for the Alphacoronavirus genus to enter human cells is APN, it is the degradation of the sialic acid co-receptor function within the O-domain that facilitates this specific transition to a human respiratory pathogen.

New nanotech imaging tool may allow smartphone disease diagnosis

This new technology could allow people to use the camera on their smartphone to diagnose diseases.
Credit: TMOS

Scientists have developed a low-cost microscopic imaging device small enough to fit on a smartphone camera lens, with the potential to make mobile medical diagnosis of diseases affordable and accessible.

Research published today in ACS Photonics from researchers at the University of Melbourne and the Australian Research Council Centre of Excellence for Transformative Meta-Optical Systems (TMOS), is helping miniaturize phase-imaging technology using metasurfaces, which are only a few hundred nanometers thick – about 350 times thinner than the thickness of a human hair – thus small enough to fit in the lens of a smartphone or other small camera.

The detection of diseases often relies on optical microscope technology to investigate changes in biological cells. Currently, these investigation methods usually involve staining the cells with chemicals in a laboratory environment as well as using specialized ‘phase-imaging’ microscopes. These aim to make invisible aspects of a biological cell visible, so early-stage detection of disease becomes possible. However, phase-imaging microscopes are bulky and cost thousands of dollars, putting them out of reach of remote medical practices.

‘Resetting’ the injured brain offers clues for concussion treatment

Jonathan Godbout, professor of neuroscience
Credit: Ohio State University

New research in mice raises the prospects for development of post-concussion therapies that could ward off cognitive decline and depression, two common conditions among people who have experienced a moderate traumatic brain injury.

The study in mice clarified the role of specific immune cells in the brain that contribute to chronic inflammation. Using a technique called forced cell turnover, researchers eliminated these cells in the injured brains of mice for a week and then let them repopulate for two weeks.

“It’s almost like hitting the reset button,” said senior study author Jonathan Godbout, professor of neuroscience in The Ohio State University College of Medicine.

Compared to brain-injured mice recovering naturally, mice that were given the intervention showed less inflammation in the brain and fewer signs of thinking problems 30 days after the injury.

Though temporarily clearing away these cells, called microglia, in humans isn’t feasible, the findings shed light on pathways to target that could lower the brain’s overall inflammatory profile after a concussion, potentially reducing the risk for behavioral and cognitive problems long after the injury.

“In a moderate brain injury, if the CT scan doesn’t show damage, patients go home with a concussion protocol. Sometimes people come back weeks, months later with neuropsychiatric issues. It’s a huge problem affecting millions of people,” said Godbout, faculty director of Ohio State’s Chronic Brain Injury Program and assistant director of basic science in the Institute for Behavioral Medicine Research.

Hydroponic native plants to detox PFAS-contaminated water

PFAS can be removed from contaminated water by Australian native rushes.

They’re the non-stick on Teflon cookware, the stain resistance in Scotchgard, and the suppression factor in firefighting foam, but while the staying power of PFAS chemicals was once revered, it’s now infamous as PFAS substances continue to infiltrate the environment and affect human health.

Now, new research from the University of South Australia is helping to remediate the ‘indestructible’ PFASs as scientists show that Australian native plants can significantly remediate PFAS pollutants through floating wetlands to create healthier environments for all.

Conducted in partnership with CSIRO and the University of Western Australia, the research found that PFAS chemicals (per- and poly-fluoroalkyl substances) can be removed from contaminated water via Australian native rushes - Phragmites australis, Baumea articulata, and Juncus kraussii.

Phragmites australis, otherwise known as the common reed, removed legacy PFAS contaminants by 42-53 per cent from contaminated surface water (level: 10 µg/L).

Decreased Genetic Diversity in Immune System Could Impact Endangered Toad Survival

Anaxyrus baxteri, the Wyoming toad.

A new study from North Carolina State University examines immune system diversity in the critically endangered Wyoming toad and finds that genetic bottlenecks could impact a species’ ability to respond to new pathogens. The findings could inform captive breeding strategies for endangered animal populations.

The Wyoming toad, Anaxyrus baxteri, suffered a severe population decline throughout the latter part of the 20th century due to factors including habitat destruction and fungal infection. The toad was brought into a captive breeding program in the 1990s in order to save the species. Scientists estimate a current wild population of only 400 to 1,500 animals, meaning that the toad is considered critically endangered.

“Population reduction in this species created a genetic bottleneck to begin with, meaning the level of genetic diversity is already very small,” says Jeff Yoder, professor of comparative immunology at NC State and co-corresponding author of a paper describing the work. “This is the first study to look specifically at genetic diversity in the immune systems of these toads and how it could impact them as a population.”

Yoder, with co-corresponding author Alex Dornburg of the University of North Carolina at Charlotte, performed RNA sequencing on immune tissues from three healthy, retired Wyoming toad breeders. Study co-author Michael Stoskopf, who was on the Wyoming Toad Recovery Implementation Team established in 2008, obtained the samples.

Search reveals eight new sources of black hole echoes

In this illustration, a black hole pulls material off a neighboring star and into an accretion disk.
Credits: Aurore Simonnet and NASA’s Goddard Space Flight Center

Scattered across our Milky Way galaxy are tens of millions of black holes — immensely strong gravitational wells of spacetime, from which infalling matter, and even light, can never escape. Black holes are dark by definition, except on the rare occasions when they feed. As a black hole pulls in gas and dust from an orbiting star, it can give off spectacular bursts of X-ray light that bounce and echo off the inspiraling gas, briefly illuminating a black hole’s extreme surroundings.

Now MIT astronomers are looking for flashes and echoes from nearby black hole X-ray binaries — systems with a star orbiting, and occasionally being eaten away by, a black hole. They are analyzing the echoes from such systems to reconstruct a black hole’s immediate, extreme vicinity.

In a study appearing today in the Astrophysical Journal, the researchers report using a new automated search tool, which they’ve coined the “Reverberation Machine,” to comb through satellite data for signs of black hole echoes. In their search, they have discovered eight new echoing black hole binaries in our galaxy. Previously, only two such systems in the Milky Way were known to emit X-ray echoes.

In comparing the echoes across systems, the team has pieced together a general picture of how a black hole evolves during an outburst. Across all systems, they observed that a black hole first undergoes a “hard” state, whipping up a corona of high-energy photons along with a jet of relativistic particles that is launched away at close to the speed of light. The researchers discovered that at a certain point, the black hole gives off one final, high-energy flash, before transitioning to a “soft,” low-energy state.

Researchers Create Self-Assembled Logic Circuits from Proteins

In a proof-of-concept study, researchers have created self-assembled, protein-based circuits that can perform simple logic functions. The work demonstrates that it is possible to create stable digital circuits that take advantage of an electron’s properties at quantum scales.

One of the stumbling blocks in creating molecular circuits is that as the circuit size decreases the circuits become unreliable. This is because the electrons needed to create current behave like waves, not particles, at the quantum scale. For example, on a circuit with two wires that are one nanometer apart, the electron can “tunnel” between the two wires and effectively be in both places simultaneously, making it difficult to control the direction of the current. Molecular circuits can mitigate these problems, but single-molecule junctions are short-lived or low-yielding due to challenges associated with fabricating electrodes at that scale.

“Our goal was to try and create a molecular circuit that uses tunneling to our advantage, rather than fighting against it,” says Ryan Chiechi, associate professor of chemistry at North Carolina State University and co-corresponding author of a paper describing the work.

Global warming accelerates the water cycle, with relevant climatic consequences

Global warming could lead to a destabilization of the global climate system
Credit: /ICM-CSIC.

According to a new study led by the ICM-CSIC, this could lead to a destabilization of the global climate system, an intensification of storms in specific areas, and an acceleration of ice melting at the poles.

Researchers at the Institut de Ciències del Mar (ICM-CSIC) in Barcelona have found that global warming is accelerating the water cycle, which could have significant consequences on the global climate system, according to an article published recently in the journal Scientific Reports.

This acceleration of the water cycle is caused by an increase in the evaporation of water from the seas and oceans resulting from the rise in temperature. As a result, more water is circulating in the atmosphere in its vapor form, 90 per cent of which will eventually precipitate back into the sea, while the remaining 10 per cent will precipitate over the continent.

New Model for Antibacterial Mechanism

Brookhaven Lab biologist Paul Freimuth and co-author Feiyue Teng, a scientist in Brookhaven Lab's Center for Functional Nanomaterials (CFN), at the light microscope used to image bacteria in this study.
Credit: Brookhaven National Laboratory

Biologists at the U.S. Department of Energy’s Brookhaven National Laboratory and their collaborators have discovered an aberrant protein that’s deadly to bacteria. In a paper just published in the journal PLOS ONE, the scientists describe how this erroneously built protein mimics the action of aminoglycosides, a class of antibiotics. The newly discovered protein could serve as a model to help scientists unravel details of those drugs’ lethal effects on bacteria—and potentially point the way to future antibiotics.

“Identifying new targets in bacteria and alternative strategies to control bacterial growth is going to become increasingly important,” said Brookhaven biologist Paul Freimuth, who led the research. Bacteria have been developing resistance to many commonly used drugs, and many scientists and doctors have been concerned about the potential for large-scale outbreaks triggered by these antibiotic-resistant bacteria, he explained.

“What we’ve discovered is a long way from becoming a drug, but the first step is to understand the mechanism,” Freimuth said. “We’ve identified a single protein that mimics the effect of a complex mixture of aberrant proteins made when bacteria are treated with aminoglycosides. That gives us a way to study the mechanism that kills the bacterial cells. Then maybe a new family of inhibitors could be developed to do the same thing.”

Revealing the secret language of dark matter

In the Universe, dark matter and standard matter “talk” to each other using a secret language. This “discussion” happens thanks to gravity, scientists say, but not in a way they can fully comprehend. A new SISSA study published in The Astrophysical Journal sheds light on this long-standing issue. The authors of the research, Ph.D Student Giovanni Gandolfi and supervisors Andrea Lapi and Stefano Liberati, propose a special property for dark matter called “non-minimal coupling with gravity”. This new type of interaction can modify dark matter gravitational influence on standard 'baryonic' matter.

According to the authors, the 'non-minimal coupling' could be the key to decrypting the enigmatic dialogue between the two components, possibly solving one of the biggest open questions about dark matter's nature. To prove the hypothesis, the assumption has been tested and then confirmed with experimental data from thousands of spiral galaxies.

The mysterious interplay with standard matter

“Dark matter is everywhere” says the research’s authors. “Like a cosmic scaffolding, it interconnects the Universe and holds galaxies together. Dark matter is as important as mysterious, though. Possibly, one of dark matter's greatest enigmas is its interplay with standard matter, or 'baryons'”. We know that in this dialogue gravity has an important role, but scientists still don’t entirely understand the phenomenon. “For this reason,” say Gandolfi, Lapi and Liberati “we asked ourselves: is gravity wrong or are we just missing something crucial about dark matter's nature? What if dark matter and standard 'baryonic' matter do not communicate in the way we have always imagined? With our research, we have tried to answer these intriguing questions”.