New geological study: Scandinavia was born in Greenland

The oldest Scandinavian bedrock was 'born' in Greenland according to a new geological study from the University of Copenhagen. The study helps us understand the origin of continents and why Earth is the only planet in our solar system with life.

 NEWS RELEASE 21-MAR-2024
UNIVERSITY OF COPENHAGEN - FACULTY OF SCIENCE

 

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IN A FINNISH OUTCROP NESTLED BETWEEN SOME OF NORTHERN EUROPE'S OLDEST MOUNTAINS, RESEARCHERS HAVE FOUND TRACES OF A PREVIOUSLY HIDDEN PART OF EARTH'S CRUST THAT POINTS MORE THAN THREE BILLION YEARS BACK IN TIME AND NORTH TOWARDS GREENLAND.

THESE TRACES WERE FOUND IN THE MINERAL ZIRCON, WHICH AFTER CHEMICAL ANALYSES, INDICATED TO RESEARCHERS FROM THE DEPARTMENT OF GEOSCIENCES AND NATURAL RESOURCE MANAGEMENT THAT THE "FOUNDATION" UPON WHICH DENMARK AND SCANDINAVIA REST, WAS PROBABLY 'BORN' FROM GREENLAND APPROXIMATELY 3.75 BILLION YEARS AGO.

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CREDIT: ANDREAS PETERSSON

In a Finnish outcrop nestled between some of Northern Europe's oldest mountains, researchers have found traces of a previously hidden part of Earth's crust that points more than three billion years back in time and north towards Greenland.

These traces were found in the mineral zircon, which after chemical analyses, indicated to researchers from the Department of Geosciences and Natural Resource Management that the "foundation" upon which Denmark and Scandinavia rest, was probably 'born' from Greenland approximately 3.75 billion years ago.

"Our data suggest that the oldest part of Earth's crust beneath Scandinavia originates in Greenland and is about 250 million years older than we previously thought," says Professor Tod Waight, a geologist at the Department of Geosciences and Natural Resource Management.

The researchers’ study of the zircon showed that, in several ways, its chemical fingerprint matches those of some of the oldest rocks on the planet found in West Greenland’s North Atlantic Craton.

"The zircon crystals we found in river sand and rocks from Finland have signatures that point towards them being much older than anything ever found in Scandinavia, while matching the age of Greenlandic rock samples. At the same time, the results of three independent isotope analyses confirm that Scandinavia's bedrock was most likely linked to Greenland," says Department of Geosciences and Natural Resource Management researcher Andreas Petersson.

A water world without oxygen

Denmark, Sweden, Norway and Finland rest atop a part of Earth's crust known as the Fennoscandian Shield, or the Baltic Shield. The researchers believe that it broke away from Greenland as a "seed" and shifted for hundreds of millions of years until it "took root" where Finland is today.

Here, the plate grew as new geological material accumulated around it, until it became Scandinavia. At the time of the crust’s detachment from Greenland, the planet looked very different than today.

"Earth was probably a watery planet, like in the movie Waterworld, but without any oxygen in the atmosphere and without emergent crust. But, because that’s so far back in time, we can’t be really be sure about what it actually looked like," says Tod Waight. 

According to the researchers, the fact that Earth even has a continental crust composed of granite is quite special when they look out into space and compare it with other planets in our galactic neighborhood.

"This is unique in our solar system. And, evidence of liquid water and a granite crust are key factors when trying to identify habitable exoplanets and the possibility of life beyond Earth," explains Andreas Petersson.

Continents are the key to life

The new study adds pieces to a primordial continental puzzle that began long before life on Earth truly blossomed, but which has largely paved the way for both human and animal life.

"Understanding how continents formed helps us understand why ours is the only planet in the solar system with life on it. Because without fixed continents and water in between them, we wouldn't be here. Indeed, continents influence both ocean currents and climate, which are crucial for life on Earth," says Andreas Petersson.

Furthermore, the new study contributes to a growing number of studies which reject the means used thus far to calculate how continents have grown – especially during the first billion years of Earth's history.

"The most commonly used models assume that Earth’s continental crust began to form when the planet was formed, about 4.6 billion years ago. Instead, our and several other recent studies suggest that the chemical signatures showing growth of the continental crust can only be identified about a billion years later. This means that we may need to revise much of what we thought about how early continents evolved," says Professor Waight. 

At the same time, results of the study add to previous research that found similar "seeds" from ancient crusts in other parts of the world.

"Our study provides us with another important clue in the mystery of how continents formed and spread across Earth – especially in the case of the Fennoscandian Shield. But there is still plenty that we don't know. In Australia, South Africa and India, for example, similar seeds have been found, but we’re unsure of whether they all come from the same "birthplace", or whether they originated independently of one another in several places on Earth. This is something that we would like to investigate more using the method we used in this study," concludes Professor Waight.

 

About the study

• The study demonstrates that the oldest part of Earth's crust beneath Scandinavia comes from Greenland and is about 250 million years older than once thought.
• Therefore, Denmark and Scandinavia’s geologic foundation was most likely connected to Greenland approximately 3.75 billion years ago.
• The researchers analysed zircons from modern river sand and rock samples from the remote Pudasjärvi and Suomujärvi regions of Finland, whose geological origins have been little studied.
• The zircon crystals found in the Finnish river sand originally crystallized in granitic magmas deep within the crust. These granites were then lifted to the surface and eroded to eventually form sand.
• The researchers used isotopic compositions of lead, hafnium and oxygen to trace the chemical fingerprint from the Fennoscandian Shield back to Greenland. 
• The study has been published in the scientific journal Geology.

 

The zircon crystals we found in river sand and rocks from Finland have signatures that point towards them being much older than anything ever found in Scandinavia, while matching the age of Greenlandic rock samples. At the same time, the results of three independent isotope analyses confirm that Scandinavia's bedrock was most likely linked to Greenland

CREDIT

Andreas Petersson

• The researchers analysed zircons from modern river sand and rock samples from the remote Pudasjärvi and Suomujärvi regions of Finland, whose geological origins have been little studied.
• The zircon crystals found in the Finnish river sand originally crystallized in granitic magmas deep within the crust. These granites were then lifted to the surface and eroded to eventually form sand.

CREDIT

Tod Waight

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JOURNAL

Geology

DOI

10.1130/G51658.1 

ARTICLE TITLE

An Eoarchean continental nucleus for the Fennoscandian Shield and a link to the North Atlantic craton

 

Researchers take major step toward developing next-generation solar cells

UNIVERSITY OF COLORADO AT BOULDER

The solar energy world is ready for a revolution. Scientists are racing to develop a new type of solar cell using materials that can convert electricity more efficiently than today’s panels. 

In a new paper published February 26 in the journal Nature Energy, a University of Colorado Boulder researcher and his international collaborators unveiled an innovative method to manufacture the new solar cells, known as perovskite cells, an achievement critical for the commercialization of what many consider the next generation of solar technology.

Today, nearly all solar panels are made from silicon, which boast an efficiency of 22%. This means silicon panels can only convert about one-fifth of the sun’s energy into electricity, because the material absorbs only a limited proportion of sunlight’s wavelengths. Producing silicon is also expensive and energy intensive.

Enter perovskite. The synthetic semiconducting material has the potential to convert substantially more solar power than silicon at a lower production cost.

“Perovskites might be a game changer,” said Michael McGehee, a professor in the Department of Chemical and Biological Engineering and fellow with CU Boulder’s Renewable & Sustainable Energy Institute. 

Scientists have been testing perovskite solar cells by stacking them on top of traditional silicon cells to make tandem cells. Layering the two materials, each absorbing a different part of the sun’s spectrum, can potentially increase the panels’ efficiency by over 50%.

“We're still seeing rapid electrification, with more cars running off electricity. We’re hoping to retire more coal plants and eventually get rid of natural gas plants,” said McGehee.  “If you believe that we're going to have a fully renewable future, then you're planning for the wind and solar markets to expand by at least five to ten- fold from where it is today.” 

To get there, he said, the industry must improve the efficiency of solar cells.

But a major challenge in making them from perovskite at a commercial scale is the process of coating the semiconductor onto the glass plates which are the building blocks of panels. Currently, the coating process has to take place in a small box filled with non-reactive gas, such as nitrogen, to prevent the perovskites from reacting with oxygen, which decreases their performance.  

“This is fine at the research stage. But when you start coating large pieces of glass, it gets harder and harder to do this in a nitrogen filled box,” McGehee said. 

McGehee and his collaborators set off to find a way to prevent that damaging reaction with the air. They found that adding dimethylammonium formate, or DMAFo, to the perovskite solution before coating could prevent the materials from oxidizing. This discovery enables coating to take place outside the small box, in ambient air. Experiments showed that perovskite cells made with the DMAFo additive can achieve an efficiency of nearly 25% on their own, comparable to the current efficiency record for perovskite cells of 26%. 

The additive also improved the cells’ stability. 

Commercial silicon panels can typically maintain at least 80% of their performance after 25 years, losing about 1% of efficiency per year. Perovskite cells, however, are more reactive and degrade faster in the air. The new study showed that the perovskite cell made with DMAFo retained 90% of its efficiency after the researchers exposed them to LED light that mimicked sunlight for 700 hours. In contrast, cells made in the air without DMAFo degraded quickly after only 300 hours. 

While this is a very encouraging result, there are 8,000 hours in one year, he noted. So longer tests are needed to determine how these cells hold up overtime. 

“It’s too early to say that they are as stable as silicon panels, but we're on a good trajectory toward that,” McGehee said. 

The study brings perovskite solar cells one step closer to commercialization. At the same time, McGehee’s team is actively developing tandem cells with a real-world efficiency of over 30% that have the same operational lifetime as silicon panels. 

McGehee leads a U.S. academic–industry partnership called Tandems for Efficient and Advanced Modules using Ultrastable Perovskites (TEAMUP). Together with researchers from three other universities, two companies and a national laboratory, the consortium received $9 million funding from the U.S. Department of Energy last year to develop stable tandem perovskites that can feasibly be used in the real world and are commercially viable. The goal is to create tandem more efficient than conventional silicon panels and equally stable over a 25-year period. 

With higher efficiency and potentially lower price tags, these tandem cells could have broader applications than existing silicon panels, including potential installation on the roofs of electric vehicles. They could add 15 to 25 miles of range per day to a car left out in the sun, enough to cover many people’s daily commutes. Drones and sailboats could also be powered by such panels.  

After a decade of research in perovskites, engineers have built perovskite cells that are as efficient as silicon cells, which were invented 70 years ago, McGehee said. “We are taking perovskites to the finish line.  If tandems work out well, they certainly have the potential to dominate the market and become the next generation of solar cells,” he said. 
 

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JOURNAL

Nature Energy

DOI

10.1038/s41560-024-01471-4 

ARTICLE TITLE

Inhibition of halide oxidation and deprotonation of organic cations with dimethylammonium formate for air-processed p–i–n perovskite solar cells

PALEONTOLOGY

Researchers name prehistoric amphibian ancestor discovered in Smithsonian collection after Kermit the Frog

Discovery sheds light on the origin of living frogs and other amphibians and pays homage to the iconic muppet

SMITHSONIAN

 

IMAGE: 

THE FOSSIL SKULL OF KERMITOPS.

THE SKULL POSSESSES A MISHMASH OF TRAITS THAT WERE DIFFERENT FROM FEATURES SEEN IN THE SKULLS OF OLDER TETRAPODS, THE ANCIENT ANCESTORS OF AMPHIBIANS AND OTHER LIVING FOUR-LEGGED VERTEBRATES. FOR EXAMPLE, THE REGION OF THE SKULL BEHIND THE ANIMAL’S EYES WAS MUCH SHORTER THAN ITS ELONGATED, CURVED SNOUT. THESE SKULL PROPORTIONS HELPED THE ANIMAL, WHICH LIKELY RESEMBLED A STOUT SALAMANDER, SNAP UP TINY GRUB-LIKE INSECTS.

 

SCIENTISTS HAVE UNCOVERED THE FOSSILIZED SKULL OF A 270-MILLION-YEAR-OLD ANCIENT AMPHIBIAN ANCESTOR IN THE COLLECTION OF THE Smithsonian’s National Museum of Natural History. IN A PAPER PUBLISHED TODAY, MARCH 21, IN THE Zoological Journal of the Linnean Society, THE TEAM OF RESEARCHERS DESCRIBED THE FOSSIL AS A NEW SPECIES OF PROTO-AMPHIBIAN, WHICH THEY NAMED KERMITOPS GRATUS IN HONOR OF THE ICONIC MUPPET, KERMIT THE FROG.

NOTE: USNM PAL 407585, DEPARTMENT OF PALEOBIOLOGY, SMITHSONIAN INSTITUTION.

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CREDIT: BRITTANY M. HANCE, SMITHSONIAN.

Scientists have uncovered the fossilized skull of a 270-million-year-old ancient amphibian ancestor in the collection of the Smithsonian’s National Museum of Natural History. In a paper published today, March 21, in the Zoological Journal of the Linnean Society, the team of researchers described the fossil as a new species of proto-amphibian, which they named Kermitops gratus in honor of the iconic Muppet, Kermit the Frog.

According to Calvin So, a doctoral student at the George Washington University and the lead author on the new paper, naming the new creature after the beloved frog character, who was created by puppeteer Jim Henson in 1955, is an opportunity to get people excited about the discoveries scientists make using museum collections.

“Using the name Kermit has significant implications for how we can bridge the science that is done by paleontologists in museums to the general public,” So said. “Because this animal is a distant relative of today’s amphibians, and Kermit is a modern-day amphibian icon, it was the perfect name for it.”

The fossilized skull—which measures just over an inch long and possesses large, oval-shaped eye sockets—was originally unearthed by the late paleontologist Nicholas Hotton III, who served as a curator in the museum’s paleobiology department for nearly 40 years. Hotton spent several field seasons excavating fossils from rock outcrops in north central Texas known as the Red Beds. The area’s rust-colored rocks date back to the early Permian period more than 270 million years ago and contain the fossilized remains of ancient reptiles, amphibians and sail-backed synapsids, the precursors to modern mammals.

Hotton and his team collected so many fossils that they were not able to study all of them in detail. This included a small proto-amphibian skull, which the team had unearthed in a rock layer known as the Clear Fork Formation in 1984. The skull was deposited in the Smithsonian’s National Fossil Collection, where it spent decades waiting for a researcher to take a closer look.

In 2021, Arjan Mann, a postdoctoral paleontologist at the museum and a former Peter Buck Fellow, was sifting through Hotton’s trove of Texas fossils when one specimen labeled as an early amphibian caught his eye.

“One fossil immediately jumped out at me—this really well preserved, mostly prepared skull,” said Mann, who serves as So’s mentor and is also a co-author on the new paper.

Mann and So teamed up to determine what kind of prehistoric creature the fossil belonged to. The skull possessed a mishmash of traits that were different from features seen in the skulls of older tetrapods, the ancient ancestors of amphibians and other living four-legged vertebrates. For example, the region of the skull behind the animal’s eyes was much shorter than its elongated, curved snout. These skull proportions helped the animal, which likely resembled a stout salamander, snap up tiny grub-like insects.

The researchers identified the fossil as a temnospondyl, a diverse group of primitive amphibian relatives that lived for over 200 million years from the Carboniferous to the Triassic periods. But because the animal’s skull sported such unique features, the scientists concluded that it belonged in an entirely new genus, which they named Kermitops. The moniker is a play on the creature’s cartoonishly wide-eyed face and is derived from a mashup of the words “Kermit” and the Greek suffix “-ops,” which means face. The researchers also christened the new animal with the species name gratus to represent their gratitude for Hotton and the rest of the team that originally unearthed the fossil.

Kermitops is notable for more than just its namesake puppet persona. The early fossil record of amphibians and their ancestors is largely fragmentary, which makes it difficult to understand how frogs, salamanders and their kin originated. Adding relatives like Kermitops into the fold is essential for fleshing out the early branches of the amphibian family tree.

“Kermitops offers us clues to bridge this huge fossil gap and start to see how frogs and salamanders developed these really specialized traits,” So said.

Mann agrees and hopes that the discovery of a previously unknown amphibian ancestor hiding in plain site will inspire other paleontologists to take a closer look at their own museum’s fossil collections.

“This is an active area of research that a lot more paleontologists need to dive back into,” Mann said. “Paleontology is always more than just dinosaurs, and there are lots of cool evolutionary stories and mysteries still waiting to be answered. We just need to keep looking.”

The new project is the latest example of the Smithsonian’s history of collaboration with  George Washington University. This collaboration provides the university’s students with access to the collections and resources of the world’s largest museum and research complex. The new paper also includes a coauthor from the Field Museum of Natural History.

About the National Museum of Natural History

            The National Museum of Natural History is connecting people everywhere with Earth’s unfolding story. It is one of the most visited natural history museums in the world. Opened in 1910, the museum is dedicated to maintaining and preserving the world’s most extensive collection of natural history specimens and human artifacts. The museum is open daily, except Dec. 25, from 10 a.m. to 5:30 p.m. Admission is free. For more information, visit the museum on its website, blog, Facebook, Twitter and Instagram.

The fossil skull of Kermitops (left) alongside a modern frog skull (Lithobates palustris, right).

Kermitops is notable for more than just its namesake puppet persona. The early fossil record of amphibians and their ancestors is largely fragmentary, which makes it difficult to understand how frogs, salamanders and their kin originated. Adding relatives like Kermitops into the fold is essential for fleshing out the early branches of the amphibian family tree.

Scientists have uncovered the fossilized skull of a 270-million-year-old ancient amphibian ancestor in the collection of the Smithsonian’s National Museum of Natural History. In a paper published today, March 21, in the Zoological Journal of the Linnean Society, the team of researchers described the fossil as a new species of proto-amphibian, which they named Kermitops gratus in honor of the iconic Muppet, Kermit the Frog.

Note: USNM PAL 407585, Department of Paleobiology (left), and USNM 230961, Division of Amphibians and Reptiles (right), Smithsonian Institution.

CREDIT

Brittany M. Hance, Smithsonian.

Arjan Mann (right), a Smithsonian postdoctoral paleontologist and former Peter Buck Fellow, and Calvin So (left), a doctoral student at George Washington University, holding the fossil skull of Kermitops in front of the Kermit the Frog puppet display in the “Entertainment Nation” exhibition at the National Museum of American History.

Scientists have uncovered the fossilized skull of a 270-million-year-old ancient amphibian ancestor in the collection of the Smithsonian’s National Museum of Natural History. In a paper published today, March 21, in the Zoological Journal of the Linnean Society, the team of researchers described the fossil as a new species of proto-amphibian, which they named Kermitops gratus in honor of the iconic Muppet, Kermit the Frog.

Note: Fossil skull of Kermitops; USNM PAL 407585, Department of Paleobiology, Smithsonian Institution.

Note: Kermit the Frog puppet; 1994.0037.01, Gift of Jim Henson Productions. From the collections at National Museum of American History, Smithsonian Institution.

CREDIT

James D. Tiller and James Di Loreto, Smithsonian.

Calvin So (left), a doctoral student at George Washington University, and Arjan Mann (right), a Smithsonian postdoctoral paleontologist and former Peter Buck Fellow, with the fossil skull of Kermitops in the Smithsonian’s National Museum of Natural History fossil collection.

“Using the name Kermit has significant implications for how we can bridge the science that is done by paleontologists in museums to the general public,” So said. “Because this animal is a distant relative of today’s amphibians, and Kermit is a modern-day amphibian icon, it was the perfect name for it.”

“This is an active area of research that a lot more paleontologists need to dive back into,” Mann said. “Paleontology is always more than just dinosaurs, and there are lots of cool evolutionary stories and mysteries still waiting to be answered. We just need to keep looking.”

Note: USNM PAL 407585, Department of Paleobiology, Smithsonian Institution.

CREDIT

Phillip R. Lee

JOURNAL

Zoological Journal of the Linnean Society

DOI

10.1093/zoolinnean/zlae012 

METHOD OF RESEARCH

Observational study

ARTICLE TITLE

A new amphibamiform from the Early Permian of Texas elucidates patterns of cranial diversity among terrestrial amphibamiforms

ARTICLE PUBLICATION DATE

21-Mar-2024

Rays were more diverse 150 million years ago than previously thought

New fossil ray species discovered in Bavarica, Germany: Aellopobatis bavarica from the Late Jurassic

Peer-Reviewed Publication

UNIVERSITY OF VIENNA

 

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AELLOPOBATIS BAVARICA: THE NEWLY DISCOVERED SPECIES, COMPLETE FOSSILS ARE ONLY KNOWN FROM GERMANY. THIS SPECIES IS ALSO THE LARGEST SPECIES OF ALL AND CAN GROW UP TO 170 CM IN SIZE.

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CREDIT: TÜRTSCHER ET AL. (2024, FIGURE 4)

In a new study recently published in the journal Papers in Palaeontology, an international team of scientists led by palaeobiologist Julia Türtscher from the University of Vienna has explored the puzzling world of rays that lived 150 million years ago and discovered a previously hidden diversity – including a new ray species. This study significantly expands the understanding of these ancient cartilaginous fish and provides further insights into a past marine ecosystem.

In her new study, palaeobiologist Julia Türtscher from the Institute of Palaeontology at the University of Vienna examined 52 fossil rays from the Late Jurassic period. These rays are 150 million years old, from a time when Europe was largely covered by the sea, except for a few islands, comparable to today's Caribbean. The Late Jurassic specimens are particularly valuable to scientists because they are among the oldest known fully preserved ray specimens. As only the teeth of fossilised rays are usually preserved, such rare skeletal finds provide exciting insights into the early evolution of this group. Although the exceptionally well-preserved fossils (from Germany, France, and the UK) have been known for some time, they have been largely unexplored. Türtscher's study is the first comprehensive analysis of the variation in body shape in these rays.

The results show a greater diversity of holomorphic (fully preserved) rays in the Late Jurassic than previously thought. "Until now, only three holomorphic ray species have been confirmed from the Late Jurassic, but thanks to this study, a total of five species have now been identified," says Türtscher. Based on their analyses, the researchers were able to confirm a fourth species that had been discussed for some time, as well as documenting and introducing a new, previously undiscovered ray species: Aellopobatis bavarica. This species, which can grow up to 170 cm long, was previously thought to be a large form of the much smaller French Spathobatis bugesiacus, which is 60 cm long. However, by analysing the skeletal structures and body shapes in detail, the scientists were able to show that Aellopobatis bavarica is a separate species.

The new results also suggest that the five species occurred in very restricted areas, but the authors are reluctant to jump to conclusions about possible endemisms: "Further studies on the tooth morphology of the specimens and subsequent comparisons with isolated teeth from other sites may help to reconstruct the palaeogeographic distribution of Late Jurassic rays," explains Türtscher.

Insight into past marine ecosystems

The results of this new study not only contribute to the understanding of the biodiversity and evolution of rays in the Upper Jurassic, but also have direct implications on the identification of fossil ray species that are known from isolated teeth solely. Continual new discoveries about these fascinating animals provide insights into the dynamics of past marine ecosystems and highlight the importance of well-preserved fossils in the reconstruction of our geological past. "We can only draw accurate conclusions about living species if we also understand the past of a group, including its evolution, its adaptations to changing environmental factors over time, and the extinction this group has faced during its evolutionary history. Palaeobiological knowledge enables us to better understand the dynamics behind evolution and extinction of species and thus aids to develop more effective conservation measures for today's endangered species" says second author Patrick L. Jambura from the Institute of Palaeontology at the University of Vienna.

Palaeobiologist Julia Türtscher in the Bavarian State Collection of Palaeontology and Geology in Munich, where several specimens of the new ray species are on display.

CREDIT

Patrick L. Jambura

JOURNAL

Papers in Palaeontology

DOI

10.1002/spp2.1552 

ARTICLE TITLE

Rostral and Body shape analyses reveal cryptic diversity of Late Jurassic batomorphs (Chondrichthyes, Elasmobranchii) from Europe.

ARTICLE PUBLICATION DATE

19-Mar-2024

 

New vaccine against a highly fatal tropical disease – and potential bioterror weapon – demonstrates efficacy in animal studies

UNIVERSITY OF CALIFORNIA - LOS ANGELES HEALTH SCIENCES

 

IMAGE: 

BURKHOLDERIA PSEUDOMALLEI INFECTING A HUMAN CELL. THE BACTERIA (RED) ARE POLYMERIZING ACTIN (GREEN).

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CREDIT: PHOTO COURTESY OF CHRISTOPHER T. FRENCH

In a mouse study, UCLA researchers tested a vaccine against the bacterium that causes melioidosis and found it was highly protective against the disease, which is endemic in many tropical areas, causing approximately 165,000 cases with 89,000 fatalities around the world each year. 

The bacterium, called Burkholderia pseudomallei, is spread through contact with contaminated soil and water through inhalation, ingestion or broken skin. It is so dangerous that it is categorized as a Tier 1 Select Agent of bioterrorism, and it can cause rapidly fatal pneumonia when inhaled in low doses. If aerosolized and unleashed in a terror attack, it could lead to widespread death.

To date there are no licensed vaccines against the bacterium, said senior author Dr. Marcus Horwitz, Distinguished Professor of Medicine, in the division of infectious diseases, and of Microbiology, Immunology and Molecular Genetics at the David Geffen School of Medicine at UCLA.

“A safe and effective vaccine is needed to prevent this disease as melioidosis is often difficult to diagnose, requires very lengthy treatment lasting three to six months, and has a high fatality rate even in high resource settings,” Horwitz said. “Such a vaccine would be of great benefit to people living in endemic regions, travelers, and military personnel stationed in these areas, and it would also reduce the risk from an intentional release of B. pseudomallei in a bioterrorist attack.” 

The study is published in the peer-reviewed journal mBio.

The researchers developed the vaccine using a bacterial vector called LVS ΔcapB as a platform to express highly immunogenic proteins from B. pseudomallei that are able to induce an immune response that later protects the host from illness and death when infected with the pathogen.  LVS ΔcapB, derived from a weakened form of a vaccine against tularemia, or “rabbit fever,” had been developed in Horwitz’s lab as a vector platform for creation of vaccines against other diseases caused by Tier 1 Select Agents such as anthrax and plague as well as tularemia.

They administered the new vaccine through both skin injection and intranasal delivery in a strain of mice that is particularly sensitive to B. pseudomallei lung infection. The researchers found that the vaccine was not only safe and non-toxic, but effective even against a highly lethal strain of the melioidosis bacteria. Intranasal administration provided better protection than skin injection, with just a single dose proving effective with long-lasting protection.

The next steps are to test the vaccine for protection against pneumonic melioidosis in a second animal model, which the Food and Drug Administration requires in the case of vaccines for which human efficacy studies cannot be conducted. If it passes that test, the vaccine would then become eligible for testing in humans for safety and immunogenicityS. The researchers will also evaluate the vaccine’s effectiveness against subcutaneous infection with B. pseudomallei, which is the way most cases of melioidosis are thought to be acquired naturally, and test it for efficacy against the closely related Tier 1 Select Agent pathogen Burkholderia mallei, which causes glanders in humans and animals.

Study co-authors are Michael Tullius, Peter Back, Saša Masleša-Galić, and Susana Nava of UCLA, and Richard Bowen of Colorado State University.

The study was funded by the National Institutes of Health (AI141390). Flow cytometry was performed in the UCLA Jonsson Comprehensive Cancer Center (JCCC) and Center for AIDS Research Flow Cytometry Core Facility that is supported by National Institutes of Health awards P30 CA016042 and 5P30 AI028697, and by the JCCC, the UCLA AIDS Institute, the David Geffen School of Medicine at UCLA, the UCLA Chancellor's Office, and the UCLA Vice Chancellor's Office of Research.

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JOURNAL

mBio

DOI

10.1128/mbio.00186-24 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

LVS ΔcapB-vectored multiantigenic melioidosis vaccines protect against lethal respiratory Burkholderia pseudomallei challenge in highly sensitive BALB/c mice

ARTICLE PUBLICATION DATE

21-Mar-2024