New branch on tree of life includes ‘lions of the microbial world’

On the left is a starving provoran. On the right, it has engulfed its prey.
Photo Credit: Tikhonenkov, Mikhailov, Gawryluk, Belyaev, Mathur, Karpov, Zagumyonnyi, Borodina, Prokina, Mylnikov, Aleoshin, and Keeling, Nature

There’s a new branch on the tree of life and it’s made up of predators that nibble their prey to death.

These microbial predators fall into two groups, one of which researchers have dubbed “nibblerids” because they, well, nibble chunks off their prey using tooth-like structures. The other group, nebulids, eat their prey whole. And both comprise a new ancient branch on the tree of life called “Provora,” according to a paper published today in the journal Nature.

Microbial lions

Like lions, cheetahs, and more familiar predators, these microbes are numerically rare but important to the ecosystem, says senior author Dr. Patrick Keeling, professor in the UBC department of botany. “Imagine if you were an alien and sampled the Serengeti: you would get a lot of plants and maybe a gazelle, but no lions. But lions do matter, even if they are rare. These are lions of the microbial world.”

Using water samples from marine habitats around the world, including the coral reefs of Curaçao, sediment from the Black and Red seas, and water from the northeast Pacific and Arctic oceans, the researchers discovered new microbes. “I noticed that in some water samples there were tiny organisms with two flagella, or tails, that convulsively spun in place or swam very quickly. Thus began my hunt for these microbes,” said first author Dr. Denis Tikhonenkov, senior researcher at the Institute for Biology of Inland Waters of the Russian Academy of Sciences.

Surprise kilonova upends established understanding of long gamma-ray bursts

This Gemini North image, superimposed on an image taken with the Hubble Space Telescope, shows the telltale near-infrared afterglow of a kilonova produced by a long GRB (GRB 211211A). This discovery challenges the prevailing theory that long GRBs exclusively come from supernovae, the end-of-life explosions of massive stars.
Image Credit: International Gemini Observatory/NOIRLab/NSF/AURA/M. Zamani; NASA/ESA

For nearly two decades, astrophysicists have believed that long gamma-ray bursts (GRBs) resulted solely from the collapse of massive stars. Now, a new study upends that long-established and long-accepted belief.

Led by Northwestern University, a team of astrophysicists has uncovered new evidence that at least some long GRBs can result from neutron star mergers, which were previously believed to produce only short GRBs.

After detecting a 50-second-long GRB in December 2021, the team began searching for the long GRB’s afterglow, an incredibly luminous and fast-fading burst of light that often precedes a supernova. But, instead, they uncovered evidence of a kilonova, a rare event that only occurs after the merger of a neutron star with another compact object (either another neutron star or a black hole).

In addition to challenging long-established beliefs about how long GRBs are formed, the new discovery also leads to new insights into the mysterious formation of the heaviest elements in the universe.

The research was published today (Dec. 7) in the journal Nature.

Developmental genetics: How germ cells cut the cord from their parent

An adult specimen of the worm C. elegans and an embryo are shown. In the adult worm, the protein BCC-1 was labelled with a fluorescent protein (GFP) to track its activity.
Photo Credit: Uni Halle / AG Christian Eckmann

For the first cell to develop into an entire organism, genes, RNA molecules and proteins have to work together in a complex way. First, this process is indirectly controlled by the mother. At a certain point in time, the protein GRIF-1 ensures that the offspring cut themselves off from this influence and start their own course of development. A research team from Martin Luther University Halle-Wittenberg (MLU) details how this process works in the journal Science Advances.

When a new organism starts to develop, the mother calls the shots. During fertilization, the egg cell and sperm fuse to form a single new cell. However, the course of cell division, and thus how a new living being forms, is initially determined by the mother cell. "Regardless of the organism, cell division is initially pre-programmed by the mother," explains geneticist Professor Christian Eckmann from MLU. The mother’s cell provides a developmental starter set that includes the first proteins as well as the RNA molecules that serve as blueprints for further proteins. All this is necessary to jump start cell division and an organism’s development.

Big Bang research: ALICE experiment at CERN starts test operation with lead ions

The ALICE detector is being opened for an upgrade.
Photo Credit: Sebastian Scheid, Goethe University

The ALICE experiment at the CERN particle accelerator center in Geneva, Switzerland, investigates the state of matter shortly after the Big Bang, also known as the quark-gluon plasma. By causing lead ions to collide with each other, it is possible to create such a quark-gluon plasma for tiny fractions of a second. Now, for the first time, a test run at CERN for the ALICE experiment has generated collision energies of 5.36 teraelectronvolts per nucleon-nucleon collision – the highest collision energy ever achieved worldwide. Researchers led by Goethe University's Harald Appelshäuser prepared the central ALICE detector for these higher collision rates, which they hope will offer new insights into the origin of the universe.

A few fractions of a second after the Big Bang, all matter in the universe constituted a kind of "elementary particle soup", known as quark-gluon plasma. By allowing heavy ions to collide in particle accelerators, it is possible to create such quark-gluon plasma for an extremely short time. Such lead ion collisions are central to the ALICE experiment at CERN's accelerator center, which aims to study the properties of matter as it existed shortly after the Big Bang.

Staph infection-induced kidney disease may be linked to bacterial gene mutation

Anjali Satoskar
Photo Credit: Ohio State University

Researchers aiming to predict which staph-infection patients might develop a related kidney disease have found a high frequency of gene mutations in the infecting bacteria of affected patients, which suggests these variants may play a role in the body’s initiation of the renal damage.

The kidney disorder is a fairly uncommon autoimmune complication to Staphylococcus aureus infection. Although it is potentially reversible with quick administration of appropriate antibiotics and effective treatment of the infection, it can also lead to kidney disease or kidney failure.

“There are many varieties of autoimmune nephritis. For most of them, suppressing the immune system is the first line of treatment, but this type is unique because you have both an ongoing severe infection as well as this autoimmune tissue-injury response happening at the same time. Immunosuppression is not an option while the infection is still active,” said study senior author Anjali Satoskar, clinical professor of pathology in the Ohio State University College of Medicine. “It can be a diagnostic as well as a therapeutic challenge.”

In an exploratory study, Satoskar and colleagues found a higher frequency of mutations affecting a group of Staphylococcus aureus genes in blood culture isolates from patients with staph-associated nephritis compared to patients having staph infections without development of autoimmune kidney disease.

Scientists Discovered Late Antique Ice Age Was Not Global

Map of the study areas and examples of three anomalous anatomical structures.
Photo Credit: Monika Grabkowska

The international group of scientists, which includes Ural dendrochronologists, found that between 536 and 550 years the temperature decreased only in the Northern Hemisphere. Scientists obtained data on trees in Eurasia, the Western and Southern Hemispheres. The results were published in Science Bulletin. The work was supported by the Russian Science Foundation (project No. 21-14-00330).

"We estimated the spatial scale of the events of the 536-540s using tree rings. We used "abnormal" rings as markers. One advantage of the approach is that the width of the annual rings responds to temperature changes mainly only in the polar regions and highlands, but abnormal rings form during extreme cold spells in trees in many regions of the Earth. Therefore, the work included data on 23 different points, including the Southern Hemisphere, that is much more than when using the width of the rings," says Rashit Khantemirov, co-author of the work, Leading Researcher of the Laboratory of Dendrochronology of the Institute of Plant and Animal Ecology, Ural Branch of the Russian Academy of Sciences, and Head Specialist of the Laboratory of Natural Science Methods in Humanities at Ural Federal University.

Unexpected speed-dependent friction

Surprisingly, the friction between the tip of an atomic force microscope and the Moiré superstructures depends on the speed at which the tip is moved across the surface.
Illustration Credit: Department of Physics and Scixel

Due to their low-friction properties, materials consisting of single atomic layers are of great interest for applications where the aim is to reduce friction — such as hard disks or moving components for satellites or space telescopes. One such example is graphene, which consists of a single layer of carbon atoms in a honeycomb arrangement and is being examined with a view to potential use as a lubricating layer. Indeed, previous studies have shown that a graphene ribbon can be moved across a gold surface with almost no friction.

Surprising results with a rough surface

If graphene is applied to a platinum surface, it has a significant impact on the measurable friction forces. Now, physicists from the University of Basel and Tel Aviv University have reported in the journal Nano Letters that, in this instance, the friction depends on the speed at which the tip of an atomic force microscope (*AFM) is moved across the surface. This finding is surprising because friction does not depend on speed according to Coulomb’s law, which applies in the macro world.

New Virus Discovered in Swiss Ticks

Ticks in Switzerland carry a new pathogen: the so-called Alongshan virus. 
Photo Credit: Erik Karits

The Alongshan virus was discovered in China only five years ago. Now researchers at the University of Zurich have found the novel virus for the first time in Swiss ticks. It appears to be at least as widespread as the tickborne encephalitis virus and causes similar symptoms. The UZH team is working on a diagnostic test to assess the epidemiological situation.

Ticks can transmit many different pathogens such as viruses, bacteria, and parasites. Of particular concern are the tickborne encephalitis virus (TBEV), which can cause inflammation of the brain and of the linings of the brain and spinal cord, and bacteria leading to the infectious Lyme disease (borreliosis). The list of pathogens transmitted by ticks continues to increase, also in Switzerland: researchers from the Institute of Virology at the University of Zurich (UZH) have now detected the Alongshan virus (ALSV) for the first time in ticks in Switzerland.

How do worms develop their gut?

a juvenile C. angaria larva, about 150 microns long.
Photo Credit: Maduro lab/UCR

Were it not for the COVID-19 pandemic, an important discovery about the development of nematodes — elongated cylindrical worms — might not have been made.

With most classes and meetings at universities and schools having moved online in 2020-2021, a husband-and-wife research team at the University of California, Riverside, finally found some time to explore a question they had been mulling over for a long time: How do nematodes distantly related to the best-studied one, Caenorhabditis elegans, make their gut, given that the genes responsible for specifying the gut in C. elegans are absent in other nematodes?

“The pandemic freed up some time for us to think about what research we would like to move forward with when the pandemic eased,” said Morris Maduro, a professor of molecular, cell and systems biology and the corresponding author of the study published in Development, a journal. “Fortunately, an experiment we conducted generated a surprising result. It turns out a simpler gene network seems to be involved in specifying the gut in nematodes related to C. elegans. An ancestral species of C. elegans appears to have duplicated and expanded this simpler gene network to make one that is more complicated, and that complicated network is the one we have been studying all this time in C. elegans.”

Harvesting Light to Grow Food and Clean Energy Together

Solar panels emit a red light over tomato plants growing in a research field at UC Davis in 2022. The work further tests the findings of a UC Davis study showing plants in agrivoltaic systems respond best to the red spectrum of light while blue light is better used for energy production.
Photo Credit: Andre Daccache/UC Davis

People are increasingly trying to grow both food and clean energy on the same land to help meet the challenges of climate change, drought and a growing global population that just topped 8 billion. This effort includes agrivoltaics, in which crops are grown under the shade of solar panels, ideally with less water.

Now scientists from the University of California, Davis, are investigating how to better harvest the sun — and its optimal light spectrum — to make agrivoltaic systems more efficient in arid agricultural regions like California.

Their study, published in Earth’s Future, a journal of the American Geophysical Union, found that the red part of the light spectrum is more efficient for growing plants, while the blue part of the spectrum is better used for solar production.