OREGON STATE UNIVERSITY

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New hydronium-ion battery presents opportunity for more sustainable energy storage

CORVALLIS, Ore. – A new type of battery developed by scientists at Oregon State University shows promise for sustainable, high-power energy storage.

It’s the world’s first battery to use only hydronium ions as the charge carrier.

The new battery provides an additional option for researchers, particularly in the area of stationary storage.

Stationary storage refers to batteries in a permanent location that store grid power – including power generated from alternative energy sources such as wind turbines or solar cells – for use on a standby or emergency basis.

Hydronium, also known as H3O+, is a positively charged ion produced when a proton is added to a water molecule. Researchers in the OSU College of Science have demonstrated that hydronium ions can be reversibly stored in an electrode material consisting of perylenetetracarboxylic dianhydridem, or PTCDA.

This material is an organic, crystalline, molecular solid. The battery, created in the Department of Chemistry at Oregon State, uses dilute sulfuric acid as the electrolyte.

Graduate student Xingfeng Wang was the first author on the study, which has been published in the journal Angewandte Chemie International Edition, a publication of the German Chemical Society.

“This may provide a paradigm-shifting opportunity for more sustainable batteries,” said Xiulei Ji, assistant professor of chemistry at OSU and the corresponding author on the research. “It doesn’t use lithium or sodium or potassium to carry the charge, and just uses acid as the electrolyte. There’s a huge natural abundance of acid so it’s highly renewable and sustainable.”

Ji points out that until now, cations – ions with a positive charge – that have been used in batteries have been alkali metal, alkaline earth metals or aluminum.

“No nonmetal cations were being considered seriously for batteries,” he said.

The study observed a big dilation of the PTCDA lattice structure during intercalation – the process of its receiving ions between the layers of its structure. That meant the electrode was being charged, and the PTCDA structure expanded, by hydronium ions, rather than extremely tiny protons, which are already used in some batteries.

“Organic solids are not typically contemplated as crystalline electrode materials, but many are very crystalline, arranged in a very ordered structure,” Ji said. “This PTCDA material has a lot of internal space between its molecule constituents so it provides an opportunity for storing big ions and good capacity.”

The hydronium ions also migrate through the electrode structure with comparatively low “friction,” which translates to high power.

“It’s not going to power electric cars,” Ji said. “But it does provide an opportunity for battery researchers to go in a new direction as they look for new alternatives for energy storage, particularly for stationary grid storage.”

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Simulated PTCDA unit cell

Marine ecologist offers suggestions for achieving a strong, lasting ‘blue economy’

BOSTON – Incentive-based solutions offer significant hope for addressing the myriad environmental challenges facing the world’s oceans – that’s the central message a leading marine ecologist delivered today in during a presentation at the annual meeting of the American Association for the Advancement of Science. 

Jane Lubchenco, a distinguished professor in the Oregon State University College of Science, shared lessons from around the world about ways “to use the ocean without using it up” as nations look to the ocean for new economic opportunities, food security or poverty alleviation.

Elizabeth Cerny-Chipman, a former postdoctoral scholar under Lubchenco who’s now a Knauss Fellow at the National Oceanic and Atmospheric Administration, co-authored the presentation, titled “Getting Incentives Right for Sustained Blue Growth: Science and Opportunities.”

In her presentation, Lubchenco pointed out that achieving the long-term potential of blue growth will require aligning short- and long-term economic incentives to achieve a diverse mix of benefits. Blue growth refers to long-term strategies for supporting sustainable growth in the marine and maritime sectors as a whole.

“If we harness human ingenuity and recognize that a healthy ocean is essential for long-term prosperity, we can tackle the enormous threats facing the ocean,” Lubchenco says, “and we can make a transition from vicious cycles to virtuous cycles.”

Lubchenco and her collaborators note that the world’s oceans are the main source of protein production for 3 billion people; are directly or indirectly responsible for the employment of more than 200 million people; and contribute $270 billion to the planet’s gross domestic product.

“The right incentives can drive behavior that aligns with both desired environmental outcomes and desirable social outcomes,” Lubchenco says.

The first step in building increased support for truly sustainable blue growth, she says, is highlighting its potential. That means working with decision-makers to promote win-win solutions with clear short-term environmental and economic benefits. Governments, industry and communities all have important roles to play, Lubchenco notes.

“Another key step is transforming the social norms that drive the behavior of the different actors, particularly in industry,” Lubchenco says. “Finally, it will be critical to take a cross-sector approach.

“Some nations, like the Seychelles, Belize and South Africa, are doing integrated, smart planning to deconflict use by different sectors while also growing their economies in ways that value the health of the ocean, which is essential to jobs and food security. They are figuring out how to be smarter about ocean uses, not just to use the ocean more intensively.”

Prior to her presentation, Lubchenco gave a related press briefing on how to create the right incentives for sustainable uses of the ocean.

In November 2016, Lubchenco, Cerny-Chipman, OSU graduate student Jessica Reimer and Simon Levin, the distinguished university professor in ecology and evolutionary biology at Princeton University, co-authored a paper on a related topic for the Proceedings of the National Academy of Sciences.

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Catch share

"Catch share" fisheries program

New protein could be key in fighting debilitating parasitic disease

CORVALLIS, Ore. – A naturally occurring protein has been discovered that shows promise as a biocontrol weapon against schistosomiasis, one of the world’s most prevalent parasitic diseases, Oregon State University researchers reported today in a new study.

Schistosomiasis is transmitted via flatworms shed by the freshwater snails that serve as the parasite’s non-human host. It’s a potentially life-threatening illness that affects more than 250 million people annually in tropical and subtropical countries, according to the World Health Organization.

The disease can cause frequent, painful or bloody urine; abdominal pain and bloody diarrhea; anemia; fever, chills and muscle aches; inflammation and scarring of the bladder; and enlargement of lymph nodes, the liver and the spleen.

While a drug called praziquantel is an effective treatment, there is no vaccination for schistosomiasis, and those who’ve had it develop no immunity.

But researchers in OSU’s College of Science have discovered a key new protein in a snail, Biomphalaria glabrata, that hosts and releases Schistosoma mansoni parasites that infect humans. Findings were published today in the journal PLOS Neglected Tropical Diseases.

Known as Grctm6, the protein seems to prevent the snails from shedding at least some of the parasites that could go on to infect people working or playing in the water where the snails live.

“Shedding none would be great, but shedding fewer could still feasibly make a difference,” said the study’s corresponding author, Euan Allan, a postdoctoral scholar in the college’s Department of Integrative Biology. “If snails are releasing a smaller number of parasites into the environment, people are less likely to be infected.”

Three variants of Grctm6 naturally occur, Allan said, and one of them confers more resistance to Schistosoma than the others.

“What’s interesting about that, from kind of an eye in the sky look, is that in the future we might be able to increase prevalence of the more resistant version and create a new population of more resistant snails without actually interfering with their biological function,” Allan said. “That’s the next step.”

Attempts to control schistosomiasis by focusing on the snail hosts date to the 1950s, but earlier efforts involved either molluscicides – poisons – or the introduction of non-host snail species to eat or compete with the hosts.

 “Those approaches bring their own slew of problems,” Allan said. “We’d anticipate far fewer ecological consequences from gene-driving one of these naturally occurring proteins into a population of snails, because they’d remain natural in pretty much every other way – just instead of being more susceptible to Schistosoma, they’d be more resistant.”

Allan says it’s not yet clear if the protein makes snails less likely to pick up the parasite in the first place, more likely to have their immune system kill it, or less likely to shed it.

“It’s speculative, but our best guess is the protein helps a snail’s immune system better recognize the parasite,” he said.

“The real take-home of the work is that we’ve discovered a completely new protein that’s never been discovered in any other species. And this protein is involved in the extent of infection in an intermediate species, and potentially involved in the extent of human infection.” 

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Euan Allan, 541-737-2993

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Schistosome mansoni Schistosome mansoni, center

Disease “superspreaders” were driving cause of 2014 Ebola epidemic

CORVALLIS, Ore. – A new study about the overwhelming importance of “superspreaders” in some infectious disease epidemics has shown that in the catastrophic 2014-15 Ebola epidemic in West Africa, about 3 percent of the people infected were ultimately responsible for infecting 61 percent of all cases.

The issue of superspreaders is so significant, scientists say, that it’s important to put a better face on just who these people are. It might then be possible to better reach them with public health measures designed to control the spread of infectious disease during epidemics.

Findings were reported this week in Proceedings of the National Academy of Sciences.

The researchers concluded that Ebola superspreaders often fit into certain age groups and were based more in the community than in health care facilities. They also continued to spread the disease after many of the people first infected had been placed in care facilities, where transmission was much better controlled.

If superspreading had been completely controlled, almost two thirds of the infections might have been prevented, scientists said in the study. The researchers also noted that their findings were conservative, since they only focused on people who had been buried safely.

This suggests that the role of superspreaders may have been even more profound than this research indicates.

The research was led by Princeton University, in collaboration with scientists from Oregon State University, the London School of Hygiene and Tropical Medicine, the International Federation of Red Cross and Red Crescent Societies, the Imperial College London, and the National Institutes of Health.

The concept of superspreaders is not new, researchers say, and it has evolved during the 2000s as scientists increasingly appreciate that not all individuals play an equal role in spreading an infectious disease.

Superspreaders, for instance, have also been implicated in the spread of severe acute respiratory syndrome, or SARS, in 2003; and the more recent Middle East respiratory syndrome in 2012.

But there’s less understanding of who and how important these superspreaders are.

“In the recent Ebola outbreak it’s now clear that superspreaders were an important component in driving the epidemic,” said Benjamin Dalziel, an assistant professor of population biology in two departments of the College of Science at Oregon State University, and co-author of the study.

“We now see the role of superspreaders as larger than initially suspected. There wasn’t a lot of transmission once people reached hospitals and care centers. Because case counts during the epidemic relied heavily on hospital data, those hospitalized cases tended to be the cases we ‘saw.’

“However, it was the cases you didn’t see that really drove the epidemic, particularly people who died at home, without making it to a care center. In our analysis we were able to see a web of transmission that would often track back to a community-based superspreader.”

Superspreading has already been cited in many first-hand narratives of Ebola transmission. This study, however, created a new statistical framework that allowed scientists to measure how important the phenomenon was in driving the epidemic. It also allowed them to measure how superspreading changed over time, as the epidemic progressed, and as control measures were implemented.

The outbreak size of the 2014 Ebola epidemic in Africa was unprecedented, and early control measures failed. Scientists believe that a better understanding of superspreading might allow more targeted and effective interventions instead of focusing on whole populations.

“As we can learn more about these infection pathways, we should be better able to focus on the types of individual behavior and demographics that are at highest risk for becoming infected, and transmitting infection,” Dalziel said.

Researchers pointed out, for instance, that millions of dollars were spent implementing message strategies about Ebola prevention and control across entire countries. They suggest that messages tailored to individuals with higher risk and certain types of behavior may have been more successful, and prevented the epidemic from being so persistent.

Lead author on the study was Max Lau, a postdoctoral research associate at Princeton University focused on applying statistical methodology in epidemiological and ecological modelling. at Princeton University. Support and funding was provided by the Bill and Melinda Gates Foundation, the National Institutes of Health, and the UK Medical Research Council.

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Benjamin Dalziel, 541-737-1979

benjamin.dalziel@oregonstate.edu

Leading marine researcher says scientists must speak, reach out and integrate into society

CORVALLIS, Ore. – A leading global marine ecologist today called on scientists to increasingly engage the public by demonstrating the value of their research.

Jane Lubchenco, a distinguished university professor in the Oregon State University College of Science and advisor in marine studies for the university, urged this action during a time in which she said scientific facts are being called into question.

She made the points in a commentary titled “Environmental Science in a Post-Truth World” published today in Frontiers in Ecology and the Environment, the journal of the Ecological Society of America.

“Access to information, and critical thinking, are essential for an informed democracy,” Lubchenco says. “A post-truth world, a U.S. cabinet full of climate deniers, suppression of science and scientists all threaten – seriously threaten – our democracy. Resistance is appropriate, but now, more than ever, scientists also need to engage meaningfully with society to address intertwined environmental and societal problems.”

Lubchenco, an internationally recognized expert on marine ecology, environmental science and climate change, is urging researchers to act boldly and creatively to counteract what she called a “pervasive” dismissal of facts exemplified by President Trump’s labeling of climate change as a hoax.

She outlines three parallel approaches for scientists to “rise to the occasion, find solutions and help create a better world”:

1)    Demonstrate the merits of science by making it accessible, which includes eschewing jargon in favor of plain language and acting in such a way that shows scientists are warm, caring human beings;

2)    Provide hope by highlighting successes, creating even more successes, and figuring out how to bring them to a meaningful scale;

3)    Modify academic reward structures to incentivize public engagement as a core responsibility.

Lubchenco, a former administrator of the National Oceanic and Atmospheric Administration (2009-13) and the first U.S. Science Envoy for the Ocean (2014-16), makes those points and others in her invited editorial.

She says facts are losing ground to appeals to emotion and personal belief in the shaping of public opinion. Lubchenco sounds a clarion call for the scientific community to do everything in its power to stand up for science and also to make research findings understandable, credible, relevant and accessible.

That includes, Lubchenco says, “getting off our lofty perches and being more integrated into society.”

“Fortunately, many politicians and other citizens still believe that decisions based on science are better decisions than those not based on science,” says Lubchenco, past president of the Ecological Society of America, the nation’s largest professional society of ecologists.

The challenges of the post-truth era demand that scientists serve in a way that responds to needs through interactions with citizens based on humility, transparency and respect, she says.

“Now’s the time for all scientists to take a quantum leap into greater relevance by helping people to understand how important our work really is,” Lubchenco says. “For example, the world has finally begun to make tangible progress in addressing climate change. We can’t let a post-truth mentality derail that or the other things we do to improve people’s lives.”

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Jane Lubchenco

Globe-trotting pollutants raise some cancer risks four times higher than predicted

CORVALLIS, Ore. -- A new way of looking at how pollutants ride through the atmosphere has quadrupled the estimate of global lung cancer risk from a pollutant caused by combustion, to a level that is now double the allowable limit recommended by the World Health Organization.

The findings, published this week in the Proceedings of the National Academy of Sciences Early Edition online, showed that tiny floating particles can grow semi-solid around pollutants, allowing them to last longer and travel much farther than what previous global climate models predicted.

Scientists said the new estimates more closely match actual measurements of the pollutants from more than 300 urban and rural settings.

The study was done by scientists at Oregon State University, the Department of Energy’s Pacific Northwest National Laboratory, or PNNL, and Peking University. The research was primarily supported by PNNL.

"We developed and implemented new modeling approaches based on laboratory measurements to include shielding of toxics by organic aerosols, in a global climate model that resulted in large improvements of model predictions," said PNNL scientist and lead author Manish Shrivastava.

"This work brings together theory, lab experiments and field observations to show how viscous organic aerosols can largely elevate global human exposure to toxic particles, by shielding them from chemical degradation in the atmosphere."

Pollutants from fossil fuel burning, forest fires and biofuel consumption include air-polluting chemicals known as polycyclic aromatic hydrocarbons, or PAHs. In the United States, the Environmental Protection Agency has identified several PAHs as cancer-causing agents.

But PAHs have been difficult to represent in past climate models. Simulations of their degradation process fail to match the amount of PAH that is actually measured in the environment.

To look more closely at how far PAHs can travel while riding shielded on a viscous aerosol, the researchers compared the new model's numbers to PAH concentrations actually measured by Oregon State University scientists at the top of Mount Bachelor in the central Oregon Cascade Range.

“Our team found that the predictions with the new shielded models of PAHs came in at concentrations similar to what we measured on the mountain,” said Staci Simonich, a toxicologist and chemist in the College of Agricultural Sciences and College of Science at OSU, and international expert on the transport of PAHs.

“The level of PAHs we measured on Mount Bachelor was four times higher than previous models had predicted, and there’s evidence the aerosols came all the way from the other side of the Pacific Ocean.”

These tiny airborne particles form clouds, cause precipitation and reduce air quality, yet they are the most poorly understood aspect of the climate system.

A smidge of soot at their core, aerosols are tiny balls of gases, pollutants, and other molecules that coalesce around the core. Many of the molecules that coat the core are what's known as "organics." They arise from living matter such as vegetation -- leaves and branches, for example, or even the molecule responsible for the pine smell that wafts from forests.

Other molecules such as pollutant PAHs also stick to the aerosol. Researchers long thought that PAHs could move freely within the organic coating of an aerosol. This ease of movement allowed the PAH to travel to the surface where ozone -- a common chemical in the atmosphere -- can break it down.

But scientists' understanding of aerosols has changed in the last five years or so.

Recent experiments led by PNNL coauthor Alla Zelenyuk show that, depending on the conditions, the aerosol coatings can actually be quite viscous. If the atmosphere is cool and dry, the coating can become as viscous as tar, trapping PAHs and other chemicals. By preventing their movement, the viscous coating shields the PAHs from degradation.

Researchers developed a new way of representing PAHs in a global climate model, and ran it to simulate PAH concentrations from 2008 to 2010. They examined one of the most carcinogenic PAHs in particular, called BaP. Simulations were compared to data from 69 rural sites and 294 urban sites worldwide, and showed that predictions from shielded PAHs were far more accurate than previous, unshielded ones.

Scientists also analyzed how far the protected PAHs could travel, using both old and new models. In all cases, the shielded PAHs traveled across oceans and continents, whereas in the previous version they barely moved from their country of origin.

To look at the impact globe-trotting PAHs might have on human health, Shrivastava combined a global climate model, running either the shielded PAH scenario or the previous unshielded one, with a lifetime cancer risk assessment model developed by coauthors Huizhong Shen and Shu Tao, both then at Peking University.

Globally, the previous model predicted half a cancer death out of every 100,000 people, which is half the limit outlined by the World Health Organization (WHO) for PAH exposure. But using the new model, which showed that shielded PAHs actually travel great distances, the global risk was four times that, or two cancer deaths per 100,000 people, which exceeds WHO standards.

The WHO standards were not exceeded everywhere. It was higher in China and India and lower in the United States and Western Europe. The extent of shielding was also much lower over the tropics compared to the mid- and high-latitudes. As the aerosols traversed the warm and humid tropics, ozone could get access to the PAHs and oxidize them.

"We don't know what implications more PAH oxidation products over the tropics have for future human or environmental health risk assessments,” said Shrivastava. “We need to better understand how the shielding of PAHs varies with the complexity of aerosol composition, atmospheric chemical aging of aerosols, temperature and relative humidity. I was initially surprised to see so much oxidation over the tropics."

Other supporters of this research included the National Institute of Environmental Health Sciences, the National Science Foundation, the Ministry of Education, Youth and Sports of the Czech Republic, and the Department of Energy Office of Science.

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Staci Simonich, 541-737-9194

staci.simonich@oregonstate.edu

Mary Beckman, 509-375-3688

mary.beckman@pnnl.gov

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Pollutant transport to regions


Aerosol formation
Aerosol formation and transport

New technique could lead to safer, more efficient uranium extraction, aid environmental cleanup

CORVALLIS, Ore. – The separation of uranium, a key part of the nuclear fuel cycle, could potentially be done more safely and efficiently through a new technique developed by chemistry researchers at Oregon State University.

The technique uses soap-like chemicals known as surfactants to extract uranium from an aqueous solution into a kerosene solution in the form of hollow clusters. Aside from fuel preparation, it may also find value in legacy waste treatment and for the cleanup of environmental contamination.

The research at OSU involves a unique form of uranium discovered in 2005, uranyl peroxide capsules, and how those negatively charged clusters form in alkaline conditions. Results were recently published in the European Journal of Inorganic Chemistry.

“This is a very different direction,” said study lead author Harrison Neal, a graduate student in Oregon State’s College of Science. “A lot of the work done now is in acid, and we’re at the other end of the pH scale in base. It’s a very different approach, overall using less harmful, less toxic chemicals.”

Throughout the nuclear fuel cycle, many separations are required – in mining, enrichment and fuel fabrication, and then after fuel use, for the recovery of usable spent isotopes and the encapsulation and storage of unusable radioactive components.

“When you use nuclear fuel, the radioactive decay products poison the fuel and make it less effective,” said May Nyman, professor of chemistry at Oregon State and corresponding author on the research. “You have to take it, dissolve it, get the good stuff out and make new fuel.”

Nyman notes the work represents significant fundamental research in the field of cluster chemistry because it allows for the study of uranyl clusters in the organic phase and can pave the way to improved understanding of ion association.

“With extracting these clusters into the organic phase, the clusters themselves are hollow, so when we get them into the organic solution, they’re still containing other atoms, molecules, other ions,” Neal added. “We can study how these ions interact with these cages that they’re in. The fundamental research is understanding how the ions get inside and what they do once they’re inside because they’re stuck there.”

When the clusters form, each contains 20 to 60 uranium atoms, “so we can extract them in whole bunches instead of one at a time,” Nyman said. “It’s an atom-efficient approach.”

Existing separation techniques require two extraction molecules for every uranium ion, whereas the OSU technique requires less than one extraction molecule per ion.

Scientists from the University of Notre Dame collaborated on the research, which was supported by the U.S. Department of Energy.

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uranyl peroxide capsules

Uranyl peroxide capsules

Ancient, scary and alien-looking specimen forms a rarity in the insect world – a new order

CORVALLIS, Ore. – Researchers at Oregon State University have discovered a 100-million-year-old insect preserved in amber with a triangular head, almost-alien and “E.T.-like” appearance and features so unusual that it has been placed in its own scientific “order” – an incredibly rare event.

There are about 1 million described species of insects, and millions more still to be discovered, but every species of insect on Earth has been placed in only 31 existing orders. Now there’s one more.

The findings have been published in the journal Cretaceous Research and describe this small, wingless female insect that probably lived in fissures in the bark of trees, looking for mites, worms or fungi to feed on while dinosaurs lumbered nearby. It was tiny, but scary looking.

“This insect has a number of features that just don’t match those of any other insect species that I know,” said George Poinar, Jr., an emeritus professor of entomology in the OSU College of Science and one of the world’s leading experts on plant and animal life forms found preserved in the semi-precious stone amber.

“I had never really seen anything like it. It appears to be unique in the insect world, and after considerable discussion we decided it had to take its place in a new order.”

Perhaps most unusual, Poinar said, was a triangular head with bulging eyes, with the vertex of the right triangle located at the base of the neck. This is different from any other known insect, and would have given this species the ability to see almost 180 degrees by turning its head sideways.

The insect, probably an omnivore, also had a long, narrow, flat body, and long slender legs. It could have moved quickly, and literally seen behind itself. It also had glands on the neck that secreted a deposit that scientists believe most likely was a chemical to repel predators.

The insect has been assigned to the newly created order Aethiocarenodea, and the species has been named Aethiocarenus burmanicus, in reference to the Hukawng Valley mines of Myanmar – previously known as Burma – where it was found. Only one other specimen of this insect has been located, also preserved in Burmese amber, Poinar said.

Those two specimens, which clearly belong to the same species, now comprise the totality of the order Aethiocarenodea. The largest order of insects, by comparison, is Coleoptera, the beetles, with hundreds of thousands of known species.

Needless to say, this species from such ancient amber is long extinct. It obviously had special features that allowed it to survive in the forests of what is now Burma, 100 million years ago, but for some unknown reason it disappeared. Loss of its preferred habitat is a likely possibility.

“The strangest thing about this insect is that the head looked so much like the way aliens are often portrayed,” Poinar said. “With its long neck, big eyes and strange oblong head, I thought it resembled E.T. I even made a Halloween mask that resembled the head of this insect. But when I wore the mask when trick-or-treaters came by, it scared the little kids so much I took it off.”

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George Poinar, Jr.

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New order of insect


Strange head

Strange head


Neck glands
Neck glands

Molecule shows ability to thwart pathogens’ genetic resistance to antibiotic

CORVALLIS, Ore. – Oregon State University researchers have developed a new weapon in the battle against antibiotic-resistant germs - a molecule that neutralizes the bugs’ ability to destroy the antibiotic.

Scientists at OSU were part of an international collaboration that demonstrated the molecule’s ability to inhibit expression of an enzyme that makes bacteria resistant to a wide range of penicillins.

The molecule is a PPMO, short for peptide-conjugated phosphorodiamidate morpholino oligomer. The enzyme it combats is known as New Delhi metallo-beta-lactamase, or NDM-1, and it’s accompanied by additional genes that encode resistance to most if not all antibiotics.

“We’re targeting a resistance mechanism that’s shared by a whole bunch of pathogens,” said Bruce Geller, professor of microbiology in OSU’s College of Science and College of Agricultural Sciences, who’s been researching molecular medicine for more than a decade. “It’s the same gene in different types of bacteria, so you only have to have one PPMO that’s effective for all of them, which is different than other PPMOs that are genus specific.”

The Oregon State study showed that in vitro the new PPMO restored the ability of an antibiotic -- in this case meropenem, an ultra-broad-spectrum drug of the carbapenem class -- to fight three different genera of bacteria that express NDM-1. The research also demonstrated that a combination of the PPMO and meropenem was effective in treating mice infected with a pathogenic strain of E. coli that is NDM-1 positive.

Results of the study, supported by a grant from the National Institutes of Health, were recently published in the Journal of Antimicrobial Chemotherapy.

Geller says the PPMO will likely be ready for testing in humans in about three years.

“We’ve lost the ability to use many of our mainstream antibiotics,” Geller said. “Everything’s resistant to them now. That’s left us to try to develop new drugs to stay one step ahead of the bacteria, but the more we look the more we don’t find anything new. So that’s left us with making modifications to existing antibiotics, but as soon as you make a chemical change, the bugs mutate and now they’re resistant to the new, chemically modified antibiotic.”

That progression, Geller explains, made the carbapenems, the most advanced penicillin-type antibiotic, the last line of defense against bacterial infection.

“The significance of NDM-1 is that it is destroys carbapenems, so doctors have had to pull out an antibiotic, colistin, that hadn’t been used in decades because it’s toxic to the kidneys,” Geller said. “That is literally the last antibiotic that can be used on an NDM-1-expressing organism, and we now have bacteria that are completely resistant to all known antibiotics. But a PPMO can restore susceptibility to antibiotics that have already been approved, so we can get a PPMO approved and then go back and use these antibiotics that had become useless.”

In addition to Geller, the research team included Oregon State postdoctoral scholars Erin Sully and Lixin Li and OSU undergraduate student Christina Moody, as well as scientists from Sarepta Therapeutics, Harvard Medical School, the University of Fribourg, and the University of Texas Southwestern.

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Scientists discover a molecular motor has a “gear” for directional switching

CORVALLIS, Ore. – A study published today offers a new understanding of the complex cellular machinery that animal and fungi cells use to ensure normal cell division, and scientists say it could one day lead to new treatment approaches for certain types of cancers.

The research revealed a totally unexpected behavior about a “motor” protein that functions as chromosomes are segregated during cell division. The findings were published in Nature Communications.

The work was led by Weihong Qiu, an assistant professor of physics in the College of Science at Oregon State University, in collaboration with researchers from Henan University in China and the Uniformed Services University of the Health Sciences in Maryland.

Motor proteins are tiny molecular machines that convert chemical energy into mechanical work. They are the miniature “vehicles” of a cell, and move on a network of tracks commonly referred to as the cytoskeleton. They shuttle cellular cargos between locations and generate forces to position chromosomes. But in spite of intensive research efforts over many years, mechanisms underlying the actions of many motor proteins are still unclear.

In this study, researchers focused on a particular motor protein, called KlpA, and used a high-sensitivity light microscopy method to directly follow the movement of individual KlpA molecules on the cytoskeleton track. They discovered that KlpA is able to move in opposite directions - an unusual finding. KlpA-like motor proteins are thought to be exclusively one-way vehicles.

The researchers also discovered that KlpA contains a gear-like component that enables it to switch direction of movement. This allows it to localize to different regions inside the cell so it can help ensure that chromosomes are properly divided for normal cell division.  

“In the past, KlpA-like motor proteins were thought to be largely redundant, and as a result they haven’t been studied very much,” Qiu said.

“It’s becoming clear that KlpA-like motors in humans are crucial to cancer cell proliferation and survival. Our results help better understand other KlpA-like motor proteins including the ones from humans, which could eventually lead to novel approaches to cancer treatment.”

Qiu and colleagues say they are excited about their future research, which may uncover the design principle at the atomic level that allows KlpA to move in opposite directions. And there may be other applications.

“KlpA is a fascinating motor protein because it is the first of its kind to demonstrate bidirectional movement,” Qiu said. “It provides a golden opportunity for us to learn from Mother Nature the rules that we can use to design motor protein-based transport devices.  Hopefully in the near future, we could engineer motor protein-based robotics for drug delivery in a more precise and controllable manner.”

The work was done with partial support from the National Science Foundation.

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Weihong Qiu, 541-737-7377

weihong.qiu@physics.oregonstate.edu

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