Giant bacterium powers itself with unique processes

Micrograph of a group of Epulopiscium viviparus bacteria.
Image Credit: Esther Angert

Not all bacteria are created equal.

Most are single-celled and tiny, a few ten-thousandths of a centimeter long. But bacteria of the Epulopiscium family are large enough to be seen with the naked eye and 1 million times the volume of their better-known cousins, E. coli.

In a study published Dec. 18 in Proceedings of the National Academy of Sciences, researchers from Cornell and Lawrence Berkeley National Laboratory have for the first time described the full genome of one species of the family of giants, which they’ve named Epulopiscium viviparus.

“This incredible giant bacterium is unique and interesting in so many ways: its enormous size, its mode of reproduction, the methods by which it meets its metabolic needs and more,” said Esther Angert, professor of microbiology in the College of Agriculture and Life Sciences, and corresponding author of the study. “Revealing the genomic potential of this organism just kind of blew our minds.”

The first member of the Epulopiscium family was discovered in 1985. All members of the species live symbiotically within the intestinal tracts of certain surgeonfish in tropical marine coral reef environments, such as the Great Barrier Reef and in the Red Sea.

Recent volcanism on Mars reveals a planet more active than previously thought

This image taken by the European Space Agency's Mars Express orbiter shows an oblique view focusing on one of the vast lava flows in Elysium Planitia.
Image Credit: ESA/DLR/FU Berlin

A vast, flat, "featureless" plain on Mars surprised researchers by revealing a much more tumultuous geologic past than expected, according to a study led by researchers at the University of Arizona. Enormous amounts of lava have erupted from numerous fissures as recently as one million years ago, blanketing an area almost as large as Alaska and interacting with water in and under the surface, resulting in large flood events that carved out deep channels.

Lacking plate tectonics – shifting chunks of crust that constantly reshape Earth's surface – Mars has long been thought to be a geologically "dead" planet where not much is happening. Recent discoveries have researchers questioning this notion, however. Just last year, a team of planetary scientists, also at UArizona, presented evidence for a giant mantle plume underneath the region Elysium Planitia, driving intense volcanic and seismic activity in a relatively recent past.

In the most recent study, a team led by Joana Voigt and Christopher Hamilton at UArizona's Lunar and Planetary Laboratory combined spacecraft images and measurements from ground-penetrating radar to reconstruct in three-dimensional detail every individual lava flow in Elysium Planitia. The extensive survey revealed and documented more than 40 volcanic events, with one of the largest flows infilling a valley named Athabasca Valles with almost 1,000 cubic miles of basalt.

Plant metabolism proves more complicated than previously understood

Ying Li, associate professor of horticulture and landscape architecture at Purdue University.
Photo Credit: Purdue Agricultural Communications /Tom Campbell

Plants have evolved fiendishly complicated metabolic networks. For years, scientists focused on how plants make secondary metabolites, the compounds that plants produce to enhance their defense and survival mechanisms.

“Only recently we started appreciating that the genes involved in making those specialized, secondary metabolites are being regulated,” said Ying Li, associate professor of horticulture and landscape architecture at Purdue University. “They are turned on when plants need to make secondary metabolites. And they are turned off when plants will no longer need to make them.”

Purdue’s Natalia Dudareva, Distinguished Professor of Biochemistry and Horticulture and Landscape Architecture, said, “Also, secondary metabolites are often toxic to cells when they accumulate to high levels, as we saw when we manipulated the resistance of the barriers that volatile secondary metabolites have to pass through to be released into the atmosphere. However, cells sense the accumulation of these toxic compounds and downregulate genes responsible for the formation of precursors for these volatiles.”

Genetic sequencing uncovers unexpected source of pathogens in floodwaters

A NASA image containing visible and infrared data revealing the presence of dissolved organic matter – including potential antibiotic-resistant pathogens – in the waterways along coastal North Carolina after Hurricane Florence.
Image Credit: Courtesy NASA

Researchers report in the journal Geohealth that local rivers and streams were the source of the Salmonella enterica contamination along coastal North Carolina after Hurricane Florence in 2018 – not the previously suspected high number of pig farms in the region. 

These findings have critical implications for controlling the spread of disease caused by antibiotic-resistant pathogens after flooding events, particularly in the coastal regions of developing countries that are being highly impacted by the increase in tropical storms. 

The study, led by civil and environmental engineering professor Helen Nguyen and graduate student Yuqing Mao, tracks the presence and origin of S. enterica from environmental samples from coastal North Carolina using genetic tracing. 

“Infections caused by antibiotic-resistant pathogens are responsible for approximately 2.8 million human illnesses and 36,000 deaths per year in the U.S. alone,” Nguyen said. “These infections spread easily across the globe and are a major burden on burgeoning health care systems, but they are preventable through mitigation.”

Study underlines impact of air pollution on people with asthma

PhD researcher Amy McCarron
Faculty of Natural Sciences
"By better understanding how air pollution impacts those most vulnerable in their day to day lives and how they practically manage this, we can work towards creating more effective communications and advice aimed at encouraging behavior change."
Photo Credit: Courtesy of University of Stirling

The study could offer an opportunity to improve the effectiveness of advice.

New research by the University of Stirling has offered a greater understanding of how people with asthma in Scotland are affected by air pollution.

The study could offer an opportunity to improve the effectiveness of advice aimed at helping individuals to reduce their personal exposure to air pollution.

Asthma is the world’s most widespread chronic respiratory condition and more than 368,000 people receive treatment for asthma in Scotland, 7% of the population.

Meanwhile, air pollution causes seven million premature deaths every year, with an estimated 2500–3500 of those in Scotland.

Exposure to air pollution is a known asthma trigger and University of Stirling researchers interviewed 36 people in Scotland who spoke in detail about the impact on their lives.

Dramatic rise in antibiotic use in first year of pandemic in primary care

Excessive use of antibiotics can give rise to bacterial resistance to these drugs, making bacterial infections increasingly hard to treat
Image Credit: Arek Socha

Antibiotics have no effect on viruses, and that includes the coronavirus. Yet in the first year of the pandemic, primary care physicians in Switzerland prescribed antibacterial medications twice as frequently as before, report researchers at the University of Basel. A risky practice, warns the research team.

It was a time of great uncertainty. When the first wave of the new coronavirus swept across Switzerland in winter and spring 2020, there were no diagnostic tests, no vaccines, and no effective medications. During this precarious phase, primary care physicians based in Switzerland seem to have increasingly resorted to treating patients with antibiotics, even though these medications have no effect on viruses. This was the conclusion reached by a research team led by Professor Heiner C. Bucher from the Department of Clinical Research at the University of Basel and University Hospital Basel.

As the team reports in the journal Clinical Microbiology and Infection, the use of antibiotics doubled from around eight to 16 prescriptions per 100 consultations. During the first wave of SARS-CoV-2 at the beginning of 2020, a massive rise in prescriptions of antibiotics became apparent. Prescriptions then remained at an above-average level throughout the year compared with previous years (2017-2019).

For this emergent class of materials, ‘solutions are the problem’

Alec Ajnsztajn (left) and Jeremy Daum
Photo Credit: Gustavo Raskosky/Rice University

Rice University materials scientists developed a fast, low-cost, scalable method to make covalent organic frameworks (COFs), a class of crystalline polymers whose tunable molecular structure, large surface area and porosity could be useful in energy applications, semiconductor devices, sensors, filtration systems and drug delivery.

“What makes these structures so special is that they are polymers but they arrange themselves in an ordered, repeating structure that makes it a crystal,” said Jeremy Daum, a Rice doctoral student and lead author of a study published in ACS Nano. “These structures look a bit like chicken wire ⎯ they’re hexagonal lattices that repeat themselves on a two-dimensional plane, and then they stack on top of themselves, and that’s how you get a layered 2D material.”

Alec Ajnsztajn, a Rice doctoral alumnus and the study’s other lead author, said the synthesis technique makes it possible to produce ordered 2D crystalline COFs in record time using vapor deposition.

“A lot of times when you make COFs through solution processing, there’s no alignment on the film,” Ajnsztajn said. “This synthesis technique allows us to control the sheet orientation, ensuring that pores are aligned, which is what you want if you’re creating a membrane.”

Scientists collect aardvark poop to understand how the species is impacted by climate in Africa

Aardvark.
Photo Credit: Peter Buss

In a first-of-its-kind study of aardvarks, Oregon State University researchers spent months in sub-Saharan Africa collecting poop from the animal and concluded that aridification of the landscape is isolating them, which they say could have implications for their long-term survival.

“Everyone had heard of aardvarks and they are considered very ecologically important but there has been little study of them,” said Clint Epps, a wildlife biologist at Oregon State. “We wanted to see if we could collect enough data to begin to understand them.”

In a just-published paper in Diversity and Distribution, the researchers used genetic information gleaned from 104 aardvark poop samples to begin to understand the range of where they live.

“During times of rapid environmental change, evaluating and describing changes in the landscape where a species lives is important for informed conservation and management decisions,” said Rachel Crowhurst, a wildlife geneticist who works with Epps and co-authored the paper.

Algae as a surprising meat alternative and source of environmentally friendly protein

Photo Credit: Fraugun

With more of us looking for alternatives to eating animals, new research has found a surprising environmentally friendly source of protein – algae.

The University of Exeter study has been published in The Journal of Nutrition and is the first of its kind to demonstrate that the ingestion of two of the most commercially available algal species are rich in protein which supports muscle remodeling in young healthy adults. Their findings suggest that algae may be an interesting and sustainable alternative to animal-derived protein with respect to maintaining and building muscle.

Researcher Ino Van Der Heijden from the University of Exeter said: “Our work has shown algae could become part of a secure and sustainable food future. With more and more people trying to eat less meat because of ethical and environmental reasons, there is growing interest in nonanimal-derived and sustainably produced protein. We believe it’s important and necessary to start looking into these alternatives and we’ve identified algae as a promising novel protein source.”

Foods rich in protein and essential amino acids have the capacity to stimulate muscle protein synthesis, which can be measured in the laboratory by determining the incorporation of labelled amino acids into muscle tissue proteins and translated to a rate over time. Animal-derived protein sources robustly stimulate resting and post-exercise muscle protein synthesis.

Exoplanets' climate – it takes nothing to switch from habitable to hell

Runaway greenhouse effect can transform a temperate habitable planet with surface liquid water ocean into a hot steam dominated planet hostile to any life
Image Credit: (Chaverot et al., 2023). © Thibaut Roger / UNIGE

The Earth is a wonderful blue and green dot covered with oceans and life, while Venus is a yellowish sterile sphere that is not only inhospitable but also sterile. However, the difference between the two bears to only a few degrees in temperature. A team of astronomers from the University of Geneva (UNIGE), with the support of the CNRS laboratories of Paris and Bordeaux, has achieved a world’s first by managing to simulate the entirety of the runaway greenhouse process which can transform the climate of a planet from idyllic and perfect for life, to a place more than harsh and hostile. The scientists have also demonstrated that from the initial stages of the process, the atmospheric structure and cloud coverage undergo significant changes, leading to an almost-unstoppable and very complicated to reverse runaway greenhouse effect. On Earth, a global average temperature rise of just a few tens of degrees, subsequent to a slight rise of the Sun’s luminosity, would be sufficient to initiate this phenomenon and to make our planet inhabitable. These results are published in Astronomy & Astrophysics.

New possibilities for a healing toxin

Richard Kammerer and Oneda Leka in one of the PSI laboratories in front of an apparatus that is used, among other things, to purify proteins.
Photo Credit: Paul Scherrer Institute/Mahir Dzambegovic

PSI researchers have discovered a surprising trick that could expand the possibilities for medical use of botulinum toxin A1, better known under the name Botox, as an active agent. They have developed antibody-like proteins that speed up the enzyme’s effect on the transmission of nerve signals. This suggests that Botox might, for example, be able to relief pain more quickly than before. The study has now been published in the journal Nature Communications.

Botulinum neurotoxin A1, better known under the trademark Botox, is actually a nerve toxin produced by bacteria. It gained widespread public awareness through its use as a cosmetic aid. Many people have it injected into wrinkles to make them look younger. The substance blocks signal transmission from nerves to muscles, thus relaxing them so that facial features appear smooth. What is less well known: Botox is also used very often in therapeutic medicine to treat conditions that can be traced back to cramping muscles or faulty nerve signals, including pains, spasms, bladder weakness, grinding of teeth, and misalignments, for example of the eyes. Botox is even used in treating stomach cancer, to block the vagus nerve and thus slow down tumor growth.

In any therapy, it is crucial to use this highly effective medicine in a very targeted manner with careful dosage, since Botox is the most potent natural nerve toxin of all, which can lead to dangerous paralysis in a clinical picture called botulism. Just one hundred nanograms or so administered intravenously can be enough to kill a person, because the toxin paralyses the respiratory muscles, along with others.

AI screens for autism in the blink of an eye

Image Credit: Placidplace

With a single flash of light to the eye, artificial intelligence (AI) could deliver a faster and more accurate way to diagnose autism spectrum disorder (ASD) in children, according to new research from the University of South Australia and Flinders University.

Using an electroretinogram (ERG) - a diagnostic test that measures the electrical activity of the retina in response to a light stimulus – researchers have deployed AI to identify specific features to classify ASD.

Measuring retinal responses of 217 children aged 5-16 years (71 with diagnosed ASD and 146 children without an ASD diagnosis), researchers found that the retina generated a different retinal response in the children with ASD as compared to those who were neuro typical.

The team also found that the strongest biomarker was achieved from a single bright flash of light to the right eye, with AI processing significantly reducing the test time. The study found that higher frequency components of the retinal signal were reduced in ASD.

Conducted with University of Connecticut and University College London, the test could be further evaluated to see if these results could be used to screen for ASD among children aged 5 to 16 years with a high level of accuracy.

New research shows exercise can reduce the risk of stroke after menopause

Regular exercise could reduce the risk of stroke in post-menopausal women, according to new research partly undertaken in Swansea.
Photo Credit: Marcus Aurelius

The pilot study, which will now be followed by a more extensive, longer-term trial, suggested that the greatest benefits were to those women who exercised during or shortly after the menopause rather than many years later.

The study team, including Adrian Evans, Professor of Emergency Medicine at Swansea University Medical School, has now published its findings in the journal Heart and Circulatory Physiology.

Professor Evans said: “A vascular disease such as stroke is more common as you get older. But the incidence of stroke is higher in post-menopausal women than in men of a similar age and we are not sure why that is.

“One of the reasons, it is thought, is that before they go through the menopause, the estrogen – the hormones – have a protective effect. Post-menopause, the estrogen level is significantly reduced.

“And when they go through the menopause, they get an immune inflammatory response, which may produce abnormal clotting and changes in their blood flow, which in turn could cause a stroke.”

Electronic pathways may enhance collective atomic vibrations’ magnetism

Andrey Baydin (left) and Fuyang Tay
Photo Credit: Gustavo Raskosky/Rice University

Materials with enhanced thermal conductivity are critical for the development of advanced devices to support applications in communications, clean energy and aerospace. But in order to engineer materials with this property, scientists need to understand how phonons, or quantum units of the vibration of atoms, behave in a particular substance.

“Phonons are quite important for studying new materials because they govern several material properties such as thermal conductivity and carrier properties,” said Fuyang Tay, a graduate student in applied physics working with the Rice Advanced Magnet with Broadband Optics (RAMBO), a tabletop spectrometer in Junichiro Kono’s laboratory at Rice University. “For example, it is widely accepted that superconductivity arises from electron–phonon interactions.

“Recently, there has been growing interest in the magnetic moment carried by phonon modes that show circular motion, also known as chiral phonons. But the mechanisms that can lead to a large phonon magnetic moment are not well understood.”

Now an international team of researchers led by Felix Hernandez from Brazil’s Universidade de São Paulo and Rice assistant research professor Andrey Baydin has published a study detailing the intricate connections between the magnetic properties of these quantum whirling dervishes and a material’s underlying topology of the electronic band structure, which determines the range of energy levels that electrons have within it.

Using a fiber optic cable to study Arctic seafloor permafrost

A permafrost-created pingo or “ice pimple” in the North Slope of Alaska. Scientists from Sandia National Laboratories have been using a fiber optic cable to study permafrost in the Arctic seafloor to improve the understanding of global climate change.
Photo Credit: Courtesy of Sandia National Laboratories

The Arctic is remote, with often harsh conditions, and its climate is changing rapidly — warming four times faster than the rest of the Earth. This makes studying the Arctic climate both challenging and vital for understanding global climate change.

Scientists at Sandia National Laboratories are using an existing fiber optic cable off Oliktok Point on the North Slope of Alaska to study the conditions of the Arctic seafloor up to 20 miles from shore. Christian Stanciu, project lead, will present their latest findings on Friday, Dec. 15 at AGU’s Fall Meeting in San Francisco.

Their goal is to determine the seismic structure of miles of Arctic seafloor. Using an emerging technique, they can spot areas of the seafloor where sound travels faster than on the rest of the seafloor, typically because of more ice. They have identified several areas with lots of ice, said Stanciu, a Sandia geophysicist.

The scientists also used the cable to determine temperatures over the stretch of seafloor and monitored temperature changes over seasons. "This data, unlike any collected before, was inserted into a computer model to infer the distribution of submarine permafrost," said Jennifer Frederick, a computational geoscientist.

“One of the innovations of this project is that we can now use a single fiber to get acoustic and temperature data,” Stanciu said. “We developed a new system to remotely collect both types of data using one fiber strand. We’re getting some interesting results.”