Antibiotic use is not the only driver of superbugs

Researchers have analysed the rise of antibiotic resistance over the last 20 years in the UK and Norway, highlighting that antibiotic use is not the only factor in the increase.

Peer-Reviewed Publication

WELLCOME TRUST SANGER INSTITUTE

For the first time, researchers have analysed the impact of antibiotic use on the rise of treatment-resistant bacteria over the last 20 years in the UK and Norway. They show that while the increase in drug use has amplified the spread of superbugs, it is not the only driver.

Researchers from the Wellcome Sanger Institute, the University of Oslo, the University of Cambridge, and collaborators, conducted a high-resolution genetic comparison of bacteria. They compared over 700 new blood samples with nearly 5,000 previously sequenced bacterial samples to answer questions about what factors influence the spread of antibiotic-resistant Escherichia coli (E. coli).

The study, published today (11 January) in the Lancet Microbe, shows that greater antibiotic use does drive an increase in treatment-resistant bacteria in some instances. However, researchers confirmed that this varies depending on the type of broad-spectrum antibiotic used. They also found that the success of antibiotic-resistance genes depends on the genetic makeup of the bacteria carrying them.

Recognising all the main factors behind antibiotic resistance can help build a deeper knowledge of how these bacteria spread and what hinders them. This could then better inform public health interventions that use a complete view of the environment to help stop the spread of treatment-resistant infections.

The bacterium, E. coli is a common cause of bloodstream infections worldwide.1 The type of E. coli responsible for these infections is commonly found in the gut, where it does not cause harm. However, if it gets into the bloodstream due to a weakened immune system it can cause severe and life threatening infections.

As an added challenge for healthcare providers, antibiotic resistance, in particular multi-drug resistance (MDR), has become a frequent feature of such infections. In the UK, over 40 per cent of E. coli bloodstream infections are resistant to a key antibiotic used in the treatment of serious infections in hospital.2  

Rates of antibiotic resistance in E. coli vary globally. For example, the rate of resistance to a different antibiotic, one commonly used to treat urinary tract infections caused by E. coli, ranged from 8.4 per cent to 92.9 per cent depending on the country.3

Antibiotic resistance has been a topic of research for decades, and the surveillance data from previous studies have consistently shown an association between antibiotic use and an increased frequency of MDR in bacteria worldwide, including in the UK.  

Previous studies have suggested a stable coexistence of resistant and non-resistant E. coli strains and in some cases, the non-resistant bacteria are more successful. However, previously it was not possible to assess the role of the genetic drivers of this due to the lack of unbiased large-scale longitudinal data sets.  

This new study, from the Wellcome Sanger Institute, the University of Oslo, and collaborators, is the first time it has been possible to directly compare the success of the different strains of E. coli between two countries — Norway and the UK — and explain differences based on country-wide antibiotic usage levels.

By analysing data that spanned almost 20 years, they found that the use of antibiotics was linked to increased resistance in some instances, depending on the type of antibiotic. One class of antibiotics, non-penicillin beta-lactams, were used three to five times more on average per person in the UK compared to Norway. This has led to a higher incidence of infections by a certain multi-drug resistant E. coli strain.

However, the UK also uses the antibiotic trimethoprim more often, but analysis did not uncover higher levels of resistance in the UK when comparing the common E. coli strains found in both countries.   

The study found that the survival of MDR bacteria depended on what strains of E. coli were in the surrounding environment. Due to this and other selective pressures in an area, researchers concluded that it is not possible to assume that the widespread use of one type of antibiotic will have the same effect on antibiotic-resistant bacteria spread in different countries.

The scientists stress that their results warrant sustained research efforts to identify what else drives the spread of E. coli and other clinically important bacteria across a range of ecological settings. Further research is needed to fully understand the combined effect of antibiotics, travel, food production systems and other factors shaping the levels of drug resistance in a country.

Understanding more about the strains that can outcompete antibiotic-resistant E. coli can lead to new ways to help stop the spread. For example, attempts that increase the amount of non-resistant, non-harmful bacteria in an area.

Dr Anna Pöntinen, co-first author from the University of Oslo, Norway and visiting scientist at the Wellcome Sanger Institute, said: “Our large-scale study allowed us to start to answer some of the long-standing questions about what causally drives multidrug-resistant bacteria in a population. This research was only possible due to the national systematic surveillance of bacterial pathogens that occurred in the UK and Norway. Without such systems in place, scientists would be considerably more limited in terms of what can be learnt using the power of genomics.” 

Professor Julian Parkhill, co-author from the University of Cambridge, said: “Our study suggests that antibiotics are modulating factors in the success of antibiotic-resistant E. coli, instead of the only cause. Our research traced the impact of several different broad-spectrum antibiotics and shows that the influence of these varies by country and area. Overall, our comprehensive genetic analysis shows that it is not always possible to predict how the use of antibiotics will impact an area without knowing the genetic makeup of the bacterial strains in that environment.” 

Professor Jukka Corander, senior author from the Wellcome Sanger Institute and the University of Oslo, Norway, said: “Treatment-resistant E. coli is a major global public health issue. While it has long been accepted that the overuse of antibiotics plays a role in the rise and spread of superbugs, our study highlights that the level of drug resistance in widespread E. coli strains can vary substantially. Antibiotic use will be one selective pressure, and our study shows that it is not the only factor that impacts the success of these bacteria. Continuing to use genomics to gain a detailed understanding of the underlying drivers of bacterial success is crucial if we are to control the spread of superbugs.”

ENDS

Contact details:
Rachael Smith

Press Office
Wellcome Sanger Institute
Cambridge, CB10 1SA

Email: press.office@sanger.ac.uk

Notes to Editors:

1. Kern WV, Rieg S. (2020) Burden of bacterial bloodstream infection – A brief update on epidemiology and significance of multidrug-resistant pathogens. Clin Microbiol Infect. DOI: 10.1016/j.cmi.2019.10.031
2. UK Health Security Agency. New data shows 148 severe antibiotic-resistant infections a day in 2021. Available at: https://www.gov.uk/government/news/new-data-shows-148-severe-antibiotic-resistant-infections-a-day-in-2021#:~:text=Over%20two%2Dfifths%20of%20E,as%20cefiderocol%20to%20identify%20resistance.
3. Wang. S, Zhao. S, Zhou, et al. (2023) Antibiotic resistance spectrum of E. coli strains from different samples and age-grouped patients: a 10-year retrospective study. BMJ Open. DOI: 10.1136/bmjopen-2022-067490

Publication:

Anna Pöntinen, et al. (2024) Modulation of multi-drug resistant clone success in Escherichia coli populations: a longitudinal multi-country genomic and antibiotic usage cohort study. Lancet Microbe. DOI: 10.1016/ S2666-5247(23)00292-6

Funding:

This research was funded by the Trond Mohn Foundation, Marie Skłodowska–Curie Actions, European Research Council, the Royal Society, and Wellcome. A full acknowledgement list can be found on the publication.   

Selected websites:

About the Faculty of Medicine at the University of Oslo

Founded in 1814, the Faculty of Medicine at the University of Oslo is the oldest medical faculty in Norway. The Faculty's core activities are research, education, dissemination and innovation for the best of patients and society. https://www.med.uio.no/english/

About the University of Cambridge

The University of Cambridge is one of the world’s top ten leading universities, with a rich history of radical thinking dating back to 1209. Its mission is to contribute to society through the pursuit of education, learning and research at the highest international levels of excellence.

The University comprises 31 autonomous Colleges and 150 departments, faculties and institutions. Its 24,450 student body includes more than 9,000 international students from 147 countries. In 2020, 70.6% of its new undergraduate students were from state schools and 21.6% from economically disadvantaged areas.

Cambridge research spans almost every discipline, from science, technology, engineering and medicine through to the arts, humanities and social sciences, with multi-disciplinary teams working to address major global challenges. Its researchers provide academic leadership, develop strategic partnerships and collaborate with colleagues worldwide.

The University sits at the heart of the ‘Cambridge cluster’, in which more than 5,300 knowledge-intensive firms employ more than 67,000 people and generate £18 billion in turnover. Cambridge has the highest number of patent applications per 100,000 residents in the UK. www.cam.ac.uk

The Wellcome Sanger Institute

The Wellcome Sanger Institute is a world leader in genomics research. We apply and explore genomic technologies at scale to advance understanding of biology and improve health.  Making discoveries not easily made elsewhere, our research delivers insights across health, disease, evolution and pathogen biology. We are open and collaborative; our data, results, tools, technologies and training are freely shared across the globe to advance science.

Funded by Wellcome, we have the freedom to think long-term and push the boundaries of genomics. We take on the challenges of applying our research to the real world, where we aim to bring benefit to people and society.

Find out more at www.sanger.ac.uk or follow us on Twitter, Instagram, Facebook, LinkedIn and on our Blog.

About Wellcome
Wellcome supports science to solve the urgent health challenges facing everyone. We support discovery research into life, health and wellbeing, and we’re taking on three worldwide health challenges: mental health, infectious disease and climate and health. https://wellcome.org/

 

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JOURNAL

The Lancet Microbe

DOI

10.1016/S2666-5247(23)00292-6 

ARTICLE TITLE

Modulation of multi-drug resistant clone success in Escherichia coli populations: a longitudinal multi-country genomic and antibiotic usage cohort study

ARTICLE PUBLICATION DATE

11-Jan-2024

 

Thermal vision shows endangered numbats feel the heat of warming climate

Peer-Reviewed Publication

CURTIN UNIVERSITY

 

IMAGE: 

A BABY NUMBAT OBSERVED DURING THE STUDY

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CREDIT: CURTIN UNIVERSITY

Curtin University research using thermal imaging of numbats in Western Australia has found that during hot weather the endangered animals are limited to as little as ten minutes of activity in the sun before they overheat to a body temperature of greater than 40°C.

Lead author Dr Christine Cooper, from Curtin’s School of Molecular and Life Sciences, said despite using techniques such as raising or flattening their fur to regulate body temperature, numbats were prone to overheating, which was an important consideration for future conservation efforts, particularly given our warming climate.

“Active only during the day and with an exclusive diet of termites, numbats are often exposed to high temperatures and gain heat from direct sunlight. Even when in the shade they gain heat from radiation from the ground, rocks and trees,” Dr Cooper said.

“We found when it is cold, numbats keep warm by raising their fur to provide better insulation and to allow more radiation to penetrate. When it is hot, they depress their fur to facilitate heat loss and shield the skin from solar radiation. In this way their body functions as a thermal window that allows heat exchange.

“The numbats’ distinctive stripes do not have a role in heat balance, rather their most likely function is for camouflage.”

Dr Cooper said numbats used to be found across southern Australia but were now restricted to two remaining natural populations at Dryandra Woodland, near Narrogin, where the study was done, and Perup Nature Reserve, near Manjimup, with some additional re-introduced populations.

“With an estimated population of only about 2000, numbats are under threat from habitat loss and introduced predators like foxes and feral cats,” Dr Cooper said.

“In terms of habitat requirements, our findings show the importance of considering temperature and shade availability when planning translocations for the conservation of this endangered species, particularly given our warming climate.

“Even with shade available, higher temperatures will reduce how long numbats can forage during the day, and because they have limited capacity to become more nocturnal, heat may become problematic for numbats.

“Understanding how the numbat responds to and manages heat is essential to understanding its ecology and has particular relevance for the future conservation and management of the species in the face of global warming.”

Published in Journal of Experimental Biology, the research is titled ‘Implications of heat exchange for a free-living endangered marsupial determined by non-invasive thermal imaging’.

thermal vision of numbat from study (VIDEO)

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JOURNAL

Journal of Experimental Biology

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Implications of heat exchange for a free-living endangered marsupial determined by non-invasive thermal imaging’

ARTICLE PUBLICATION DATE

11-Jan-2024

 

A single-celled microbe is helping corals survive climate change, study finds

New research highlights the role of microorganisms in protecting corals from heat-stress

Peer-Reviewed Publication

UNIVERSITY OF MIAMI ROSENSTIEL SCHOOL OF MARINE, ATMOSPHERIC, AND EARTH SCIENCE

 

IMAGE: 

THE VIOLESCENT SEA-WHIP (PARAMURICEA CLAVATA) IS AN IMPORTANT ARCHITECT OF THE MEDITERRANEAN TEMPERATE REEFS THAT IS CURRENTLY THREATENED BY MASS MORTALITY EVENTS RELATED TO GLOBAL WARMING.

 

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CREDIT: PARENT GÉRY, VIA WIKIPEDIA CREATIVE COMMONS ATTRIBUTION-SHARE ALIKE 3.0

A Single-Celled Microbe is Helping Corals Survive Climate Change, Study Finds

New research highlights the role of microorganisms in protecting corals from heat-stress

Researchers discovered for the first time a single-celled microbe that can help corals survive ocean-warming events like bleaching. The new study, led by scientists at the University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Science and the Institute of Evolutionary Biology (IBE: CSIC-UPF) in Barcelona, offers new information on the role microbes might play in helping corals withstand end-of-century warming projections.

They found that the abundance of certain protists within the coral microbiome — the diverse microorganisms that live within corals — can inform scientists as to whether a coral will survive heat stress. These findings have important implications for corals across the globe as they face more frequent ocean warming events especially those without zooxanthellae, the symbiotic algae that is expelled from a coral during warm water-induced bleaching.

“This is the first time that a non-algae microbe has been shown to influence the ability of corals to survive a heat-stress event,” said the study’s senior author Javier del Campo, an adjunct assistant professor at the Rosenstiel School and principal investigator of the IBE, a joint center of the Spanish National Research Council (CSIC) and University Pompeu Fabra (UPF). “As corals face more and more heat-stress events due to climate change, a better understanding of all the microbes that may influence survivability can inform conservation practitioners as to which corals they should prioritize for intervention.”

To conduct the study, the international team of researchers collected coral samples from across the Mediterranean to analyze their microbiome and conduct heat-stress experiments. They amplified and sequenced two types of rRNA to look at the bacteria and protists found in the microbiome of one species of soft coral, the violescent sea-whip (Paramuricea clavata), before subjecting them to a natural heat-stress in the lab to examine signs of mortality.

Paramuricea clavata is an important architect of the Mediterranean temperate reefs that is currently threatened by mass mortality events related to global warming.

They found that a group of parasitic single-celled protists — called Syndiniales —are more common in corals that survive heat-stress, while Corallicolids, a group of protist closely related to the parasite that causes malaria in humans is more common in corals that die from heat-stress.

Protists, or single-cell eukaryotes, are less studied than bacteria in most host organisms but may have a major influence on the health of their coral host, according to the researchers

“The microbiome is a vital component of coral host health and we should study all members of it from the bacteria to the protists,” said del Campo.

The study, titled “Differential apicomplexan presence predicts thermal stress mortality in the Mediterranean coral Paramuricea clavata" was recently published in the journal Environmental Microbiology.

The study’s authors include: Anthony Bonacolta and Javier del Campo from the Rosenstiel School and the Institute of Evolutionary Biology (IBE: CSIC-UPF);  Jordi Miravall, Paula López-Sendino, Joaquim Garrabou, and Ramon Massana from the Institut de Ciències del Mar-CSIC in Barcelona, Spain; Daniel Gómez-Gras from the University of Hawai‘i at Mānoa; and Jean-Baptiste Ledoux from the Universidade do Porto in Portugal.

The study was supported by grant from the University of Miami, Agencia Estatal de Investigación (PID2020-118836GA-I00), Departament de Recerca i Universitats de la Generalitat de Catalunya (Project 2021 SGR 00420), Severo Ochoa Centre de Excellence (CEX2019-000928-S), Ministério da Educação e Ciência, Fundação para a Ciência e a Tecnologia (2021.00855) and European Union Futuremares (SEP-210597628).

About the University of Miami

The University of Miami is a private research university and academic health system with a distinct geographic capacity to connect institutions, individuals, and ideas across the hemisphere and around the world. The University’s vibrant and diverse academic community comprises 12 schools and colleges serving more than 17,000 undergraduate and graduate students in more than 180 majors and programs. Located within one of the most dynamic and multicultural cities in the world, the University is building new bridges across geographic, cultural, and intellectual borders, bringing a passion for scholarly excellence, a spirit of innovation, a respect for including and elevating diverse voices, and a commitment to tackling the challenges facing our world. Founded in the 1940’s, the Rosenstiel School of Marine, Atmospheric, and Earth Science has grown into one of the world’s premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life. www.earth.miami.edu.

 

 

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JOURNAL

Environmental Microbiology

DOI

10.1111/1462-2920.16548 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

Differential apicomplexan presence predicts thermal stress mortality in the Mediterranean coral Paramuricea clavata

Catalytic combo converts CO2 to solid carbon nanofibers

Tandem electrocatalytic-thermocatalytic conversion could help offset emissions of potent greenhouse gas by locking carbon away in a useful material

Peer-Reviewed Publication

DOE/BROOKHAVEN NATIONAL LABORATORY

 

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SCIENTISTS HAVE DEVISED A STRATEGY FOR CONVERTING CARBON DIOXIDE (CO2) FROM THE ATMOSPHERE INTO VALUABLE CARBON NANOFIBERS. THE PROCESS USES TANDEM ELECTROCATALYTIC (BLUE RING) AND THERMOCATALYTIC (ORANGE RING) REACTIONS TO CONVERT THE CO2 (TEAL AND SILVER MOLECULES) PLUS WATER (PURPLE AND TEAL) INTO "FIXED" CARBON NANOFIBERS (SILVER), PRODUCING HYDROGEN GAS (H2, PURPLE) AS A BENEFICIAL BYPRODUCT. THE CARBON NANOFIBERS COULD BE USED TO STRENGTHEN BUILDING MATERIALS SUCH AS CEMENT AND LOCK AWAY CARBON FOR DECADES.

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CREDIT: (ZHENHUA XIE/BROOKHAVEN NATIONAL LABORATORY AND COLUMBIA UNIVERSITY; ERWEI HUANG/BROOKHAVEN NATIONAL LABORATORY)

UPTON, NY—Scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and Columbia University have developed a way to convert carbon dioxide (CO2), a potent greenhouse gas, into carbon nanofibers, materials with a wide range of unique properties and many potential long-term uses. Their strategy uses tandem electrochemical and thermochemical reactions run at relatively low temperatures and ambient pressure. As the scientists describe in the journal Nature Catalysis, this approach could successfully lock carbon away in a useful solid form to offset or even achieve negative carbon emissions.

“You can put the carbon nanofibers into cement to strengthen the cement,” said Jingguang Chen, a professor of chemical engineering at Columbia with a joint appointment at Brookhaven Lab who led the research. “That would lock the carbon away in concrete for at least 50 years, potentially longer. By then, the world should be shifted to primarily renewable energy sources that don’t emit carbon.”

As a bonus, the process also produces hydrogen gas (H2), a promising alternative fuel that, when used, creates zero emissions.

Capturing or converting carbon

The idea of capturing CO2 or converting it to other materials to combat climate change is not new. But simply storing CO2 gas can lead to leaks. And many CO2 conversions produce carbon-based chemicals or fuels that are used right away, which releases CO2 right back into the atmosphere.

“The novelty of this work is that we are trying to convert CO2 into something that is value-added but in a solid, useful form,” Chen said.

Such solid carbon materials—including carbon nanotubes and nanofibers with dimensions measuring billionths of a meter—have many appealing properties, including strength and thermal and electrical conductivity. But it’s no simple matter to extract carbon from carbon dioxide and get it to assemble into these fine-scale structures. One direct, heat-driven process requires temperatures in excess of 1,000 degrees Celsius.

“It’s very unrealistic for large-scale CO2 mitigation,” Chen said. “In contrast, we found a process that can occur at about 400 degrees Celsius, which is a much more practical, industrially achievable temperature.”

The tandem two-step 

The trick was to break the reaction into stages and to use two different types of catalysts—materials that make it easier for molecules to come together and react.

“If you decouple the reaction into several sub-reaction steps you can consider using different kinds of energy input and catalysts to make each part of the reaction work,” said Brookhaven Lab and Columbia research scientist Zhenhua Xie, lead author on the paper.

The scientists started by realizing that carbon monoxide (CO) is a much better starting material than CO2 for making carbon nanofibers (CNF). Then they backtracked to find the most efficient way to generate CO from CO2.

Earlier work from their group steered them to use a commercially available electrocatalyst made of palladium supported on carbon. Electrocatalysts drive chemical reactions using an electric current. In the presence of flowing electrons and protons, the catalyst splits both CO2 and water (H2O) into CO and H2.

For the second step, the scientists turned to a heat-activated thermocatalyst made of an iron-cobalt alloy. It operates at temperatures around 400 degrees Celsius, significantly milder than a direct CO2-to-CNF conversion would require. They also discovered that adding a bit of extra metallic cobalt greatly enhances the formation of the carbon nanofibers.

“By coupling electrocatalysis and thermocatalysis, we are using this tandem process to achieve things that cannot be achieved by either process alone,” Chen said.

Catalyst characterization

To discover the details of how these catalysts operate, the scientists conducted a wide range of experiments. These included computational modeling studies, physical and chemical characterization studies at Brookhaven Lab’s National Synchrotron Light Source II (NSLS-II)—using the Quick X-ray Absorption and Scattering (QAS) and Inner-Shell Spectroscopy (ISS) beamlines—and microscopic imaging at the Electron Microscopy facility at the Lab’s Center for Functional Nanomaterials (CFN).

On the modeling front, the scientists used “density functional theory” (DFT) calculations to analyze the atomic arrangements and other characteristics of the catalysts when interacting with the active chemical environment.

“We are looking at the structures to determine what are the stable phases of the catalyst under reaction conditions,” explained study co-author Ping Liu of Brookhaven’s Chemistry Division who led these calculations. “We are looking at active sites and how these sites are bonding with the reaction intermediates. By determining the barriers, or transition states, from one step to another, we learn exactly how the catalyst is functioning during the reaction.”

X-ray diffraction and x-ray absorption experiments at NSLS-II tracked how the catalysts change physically and chemically during the reactions. For example, synchrotron x-rays revealed how the presence of electric current transforms metallic palladium in the catalyst into palladium hydride, a metal that is key to producing both H2 and CO in the first reaction stage.

For the second stage, “We wanted to know what’s the structure of the iron-cobalt system under reaction conditions and how to optimize the iron-cobalt catalyst,” Xie said. The x-ray experiments confirmed that both an alloy of iron and cobalt plus some extra metallic cobalt are present and needed to convert CO to carbon nanofibers.

“The two work together sequentially,” said Liu, whose DFT calculations helped explain the process.

“According to our study, the cobalt-iron sites in the alloy help to break the C-O bonds of carbon monoxide. That makes atomic carbon available to serve as the source for building carbon nanofibers. Then the extra cobalt is there to facilitate the formation of the C-C bonds that link up the carbon atoms,” she explained.

Recycle-ready, carbon-negative

“Transmission electron microscopy (TEM) analysis conducted at CFN revealed the morphologies, crystal structures, and elemental distributions within the carbon nanofibers both with and without catalysts,” said CFN scientist and study co-author Sooyeon Hwang.

The images show that, as the carbon nanofibers grow, the catalyst gets pushed up and away from the surface. That makes it easy to recycle the catalytic metal, Chen said.

“We use acid to leach the metal out without destroying the carbon nanofiber so we can concentrate the metals and recycle them to be used as a catalyst again,” he said.

This ease of catalyst recycling, commercial availability of the catalysts, and relatively mild reaction conditions for the second reaction all contribute to a favorable assessment of the energy and other costs associated with the process, the researchers said.

“For practical applications, both are really important—the CO2 footprint analysis and the recyclability of the catalyst,” said Chen. “Our technical results and these other analyses show that this tandem strategy opens a door for decarbonizing CO2 into valuable solid carbon products while producing renewable H2.”

If these processes are driven by renewable energy, the results would be truly carbon-negative, opening new opportunities for CO2 mitigation.

This research was supported by the DOE Office of Science (BES). The DFT calculations were performed using computational resources at CFN and at the National Energy Research Scientific Computing Center (NERSC) at DOE’s Lawrence Berkeley National Laboratory. NSLS-II, CFN, and NERSC are DOE Office of Science user facilities.

Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov.

Follow @BrookhavenLab on social media. Find us on Instagram, LinkedIn, Twitter, and Facebook.

catalytic process schematic 

The electrocatalytic-thermocatalytic tandem strategy for CNF production circumvents thermodynamic constraints by combining the co-electrolysis of CO2 and water into syngas (CO and H2) with a subsequent thermochemical process under mild conditions (370-450 °C, ambient pressure). This yields a high CNF production rate. The optimal synergy of iron-cobalt (FeCo) alloy and extra metallic Co enhanced the dissociative activation of syngas, promoting carbon-carbon bond formation for CNF production. 

CREDIT

(Zhenhua Xie/Brookhaven National Laboratory and Columbia University)

microscopic images of carbon nanofibers  

CAPTION

High-resolution transmission electron microscopy (TEM) shows the tip of the resulting carbon nanofiber (left) on the iron-cobalt/cerium oxide (FeCo/CeO2) thermocatalyst. Scientists mapped the structure and chemical composition of newly formed carbon nanofibers (right) using scanning transmission electron microscopy (STEM), high-angle annular dark field (HAADF) imaging, and energy-dispersive x-ray spectroscopy (EDS) (scale bar represents 8 nanometers). The images show that the nanofibers are made of carbon (C), and reveal that the catalytic metals, iron (Fe) and cobalt (Co), are pushed away from the catalytic surface and accumulate at the tip of the nanofiber.

CREDIT

(Center for Functional Nanomaterials/Brookhaven National Laboratory)

Related Links

• Scientific paper: "CO2 fixation into carbon nanofibers using electrochemical-thermochemical tandem catalysis"

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JOURNAL

Nature Catalysis

ARTICLE TITLE

CO2 fixation into carbon nanofibres using electrochemical–thermochemical tandem catalysis

ARTICLE PUBLICATION DATE

11-Jan-2024

 

Study uncovers potential origins of life in ancient hot springs

Peer-Reviewed Publication

NEWCASTLE UNIVERSITY

Newcastle University research turns to ancient hot springs to explore the origins of life on Earth.

The research team, funded by the UK’s Natural Environmental Research Council, investigated how the emergence of the first living systems from inert geological materials happened on the Earth, more than 3.5 billion years ago. Scientists at Newcastle University found that by mixing hydrogen, bicarbonate, and iron-rich magnetite under conditions mimicking relatively mild hydrothermal vent results in the formation of a spectrum of organic molecules, most notably including fatty acids stretching up to 18 carbon atoms in length.

Published in the journal Communications Earth & Environment, their findings potentially reveal how some key molecules needed to produce life are made from inorganic chemicals, which is essential to understanding a key step in how life formed on the Earth billions of years ago. Their results may provide a plausible genesis of the organic molecules that form ancient cell membranes, that were perhaps selectively chosen by early biochemical processes on primordial Earth.

Fatty acids in the early stages of life

Fatty acids are long organic molecules that have regions that both attract and repel water that will automatically form cell-like compartments in water naturally and it is these types of molecules that could have made the first cell membranes. Yet, despite their importance, it was uncertain where these fatty acids came from in the early stages of life. One idea is that they might have formed in the hydrothermal vents where hot water, mixed with hydrogen-rich fluids coming from underwater vents mixed with seawater containing CO2.

The group replicated crucial aspects of the chemical environment found in early Earth's oceans and the mixing of the hot alkaline water from around certain types of hydrothermal vents in their laboratory. They found that when hot hydrogen-rich fluids were mixed with carbon dioxide-rich water in the presence of iron-based minerals that were present on the early Earth it created the types of molecules needed to form primitive cell membranes.

Lead author, Dr Graham Purvis, conducted the study at Newcastle University and is currently a Postdoctoral Research Associate at Durham University.

He said: “Central to life's inception are cellular compartments, crucial for isolating internal chemistry from the external environment. These compartments were instrumental in fostering life-sustaining reactions by concentrating chemicals and facilitating energy production, potentially serving as the cornerstone of life's earliest moments.

The results suggest that the convergence of hydrogen-rich fluids from alkaline hydrothermal vents with bicarbonate-rich waters on iron-based minerals could have precipitated the rudimentary membranes of early cells at the very beginning of life. This process might have engendered a diversity of membrane types, some potentially serving as life's cradle when life first started. Moreover, this transformative process might have contributed to the genesis of specific acids found in the elemental composition of meteorites.”

Principal Investigator Dr Jon Telling, Reader in Biogeochemistry, at School of Natural Environmental Sciences, added:

“We think that this research may provide the first step in how life originated on our planet. Research in our laboratory now continues on determining the second key step; how these organic molecules which are initially ‘stuck’ to the mineral surfaces can lift off to form spherical membrane-bounded cell-like compartments; the first potential ‘protocells’ that went on to form the first cellular life.”

Intriguingly, the researchers also suggest that membrane-creating reactions similar reactions, could still be happening in the oceans under the surfaces of icy moons in our solar system today. This raises the possibility of alternative life origins in these distant worlds.

Reference

Purvis, G., Šiller, L., Crosskey, A. et al. Generation of long-chain fatty acids by hydrogen-driven bicarbonate reduction in ancient alkaline hydrothermal vents. Commun Earth Environ 5, 30 (2024). https://doi.org/10.1038/s43247-023-01196-4

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JOURNAL

Communications Earth & Environment

DOI

10.1038/s43247-023-01196-4 

METHOD OF RESEARCH

Computational simulation/modeling

ARTICLE TITLE

Generation of long-chain fatty acids by hydrogen-driven bicarbonate reduction in ancient alkaline hydrothermal vents

ARTICLE PUBLICATION DATE

10-Jan-2024

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