OREGON STATE UNIVERSITY

college of science

Lionfish analysis reveals most vulnerable prey as invasion continues

CORVALLIS, Ore. – If you live in lionfish territory in the Atlantic Ocean, the last thing you want to be is a small fish with a long, skinny body, resting by yourself at night, near the bottom of the seafloor.

If so, your chances of being gobbled up by a lionfish increase by about 200 times.

Findings of a study on lionfish predation behavior, which may also apply to some other fish and animal species, have shed some new light on which types of fish are most likely to face attack by this invasive predator, which has disrupted ecosystems in much of the Caribbean Sea and parts of the Atlantic Ocean.

The research has been published in the Journal of Animal Ecology by scientists from Oregon State University and Simon Fraser University. It used the study of lionfish to gain broader insights into how predators select their prey, and developed a new method for predicting diet selection across various prey assemblages.

“With species now moving all over the world in both marine and terrestrial systems, we need to know who will eat whom when species encounter each other for the first time,” said Stephanie Green, the David H. Smith Conservation Research Fellow in the OSU College of Science, who has done extensive studies of lionfish.

“Normally, predator-prey experiments take a lot of effort and time,” Green said. “But there are mathematical techniques that can help us better understand what is happening when we observe animals hunting in the wild, and why some species get eaten and others don’t.”

Green said that researchers want to identify common features across the animal kingdom that make some species more vulnerable than others.

“We’re playing catch-up on this,” she said. “However, with the case of species invasions, a much better understanding of which native species are at risk can help us target management intervention. This could help avoid extirpations and, in the worst-case scenario, more outright extinctions.”

This study is one of the first to identify general traits of prey that predict vulnerability to predation, and examine diet selection at different spatial scales. Some of the findings may be relevant to other invasive species problems, such as expansion of the Burmese python in the Florida Everglades and the spread of Asian tiger prawn into the Gulf of Mexico.

The study also showed that although lionfish have a voracious appetite and will eat almost any fish smaller than they are, they do have their favorites.

They find it easier to stalk and attack solitary fish, rather than those in schools. They like to hunt at dusk, near the bottom, and for some reason tend to avoid fish that clean off parasites from other fish species that are common in a marine environment.

“Fish that clean parasites off of other fish appear to be avoided by lionfish,” Green said. “Those that don’t will be much harder hit.”

Having all the traits that make them vulnerable, for instance, raises a serious question about the ability of some species to survive the lionfish invasion, such as the Exuma Goby, a small fish native to one area of The Bahamas. It has many traits lionfish prefer.

OSU researchers are working with the International Union for Conservation of Nature to help identify some of the species and problem areas most at risk of extinction from the lionfish invasion, and where control of the invaders should be prioritized.

Lionfish are now established on coral reefs across the western Atlantic Ocean, Caribbean Sea and Gulf of Mexico, and the invasion continues to spread while reef biodiversity and biomass rapidly declines. The high rate of fish mortality also poses an additional threat to coral reefs themselves, which can become covered with algae if enough fish are not present to eat the algae and keep it under control.

The research was supported by the Natural Science and Engineering Research Council of Canada and the David H. Smith Conservation Research Program.

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Stephanie Green, 778-808-0758

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Reef research
Stephanie Green


Hunting lionfish
Hunting lionfish


Lionfish
Hunting at dusk


Algae on coral reef
Algae-covered corals


“Picky Eaters,” a Podcast about species diet preferences, is online at: http://bit.ly/1vpMcAA

“Eyespots” in butterflies shown to distract predatory attack

CORVALLIS, Ore. – Research has demonstrated with some of the first experimental evidence that coloration or patterns can be used to “deflect” attacks from predators, protecting an animal’s most vulnerable parts from the predators most likely to attack them.

The study, published today in Proceedings of the Royal Society B, in fact shows that one species of butterfly uses its “eyespots” not only for protection, but varies the color and intensity of them by season as the types of predators change.

The findings were made by researchers from Oregon State University, Yale University and four other institutions.

“Eyespots are conspicuous, they draw your attention and are thought to be used by many animal species to avoid death or attack, by either startling or confusing the predator,” said Katy Prudic, lead author on the study and a researcher with the Department of Integrative Biology in the College of Science at Oregon State University. “Many insects have eyespots, which suggests they are an important adaptation.”

The butterfly species studied, Bycyclus anyana, produces about five generations a year during both wet and dry seasons in its native habitat. Through a process scientists call “phenotypic plasticity,” the same genes can produce two different eyespot patterns in the adults. Warm temperatures of the wet season create large and bright eyespots, while cool temperatures common in the dry season produce dull and small eyespots.

During the wet season, the large eyespots make a colorful target for attack, conceptually similar to a matador waving a cape that distracts a charging bull into attacking the wrong thing.

In this season, predatory insects such as the praying mantids are their greatest enemy, and the showy eyespots on the wings led the mantids to attack the butterfly wings rather than the more vulnerable body or head. The wings are badly damaged, but the insect can escape and live to reproduce.

During the dry season, most insect predators are dead but birds abound. For birds, the smaller, dull eyespots make the butterfly more difficult to detect and consume.

“Having the right type of eyespot in the right season allowed the butterflies to live long enough to lay eggs and have more offspring in the next generation,” Prudic said. “With the wrong eyespot at the wrong time, they were quickly annihilated by the mantids.”

Color pattern has always been a form of protection against predators in nature, Prudic said. It can take the form of camouflage, mimicry, delaying or redirecting attacks. But studies that observed and hypothesized about such changes have been difficult to document in controlled experiments such as this.

Eyespots are one of nature’s favorite forms of misdirection, shared by fish, frogs, birds, and many insects. Aside from deflecting attack, they can also be used as a “startle” mechanism, being flashed just long enough to delay attack briefly and allow a species to escape. Researchers also believe eyespots can play a role in sexual attraction and mate selection.

This research was supported by the Yale Institute for Biospheric Studies, the Donnelley family and the Singapore Ministry of Education.

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Kathleen Prudic, 541-737-5736

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Wet season
Wet season


Dry season
Dry season


Butterfly eyespots YouTube video http://youtu.be/0d9fzaxjvYs


Mantids attack YouTube video http://youtu.be/BObK3vzXf7g

Rivers recover natural conditions quickly following dam removal

 

The study this story is based on is available online: http://bit.ly/1rdQ4wL

CORVALLIS, Ore. – A study of the removal of two dams in Oregon suggests that rivers can return surprisingly fast to a condition close to their natural state, both physically and biologically, and that the biological recovery might outpace the physical recovery.

The analysis, published by researchers from Oregon State University in the journal PLOS One, examined portions of two rivers – the Calapooia River and Rogue River. It illustrated how rapidly rivers can recover, both from the long-term impact of the dam and from the short-term impact of releasing stored sediment when the dam is removed.

Most dams have decades of accumulated sediment behind them, and a primary concern has been whether the sudden release of all that sediment could cause significant damage to river ecology or infrastructure.

However, this study concluded that the continued presence of a dam on the river constituted more of a sustained and significant alteration of river status than did the sediment pulse caused by dam removal.

“The processes of ecological and physical recovery of river systems following dam removal are important, because thousands of dams are being removed all over the world,” said Desirée Tullos, an associate professor in the OSU Department of Biological and Ecological Engineering.

“Dams are a significant element in our nation’s aging infrastructure,” she said. “In many cases, the dams haven’t been adequately maintained and they are literally falling apart. Depending on the benefits provided by the dam, it’s often cheaper to remove them than to repair them.”

According to the American Society of Civil Engineers, the United States has 84,000 dams with an average age of 52 years. Almost 2,000 are now considered both deficient and “high hazard,” and it would take $21 billion to repair them. Rehabilitating all dams would cost $57 billion. Thus, the removal of older dams that generate only modest benefits is happening at an increasing rate.

In this study, the scientists examined the two rivers both before and after removal of the Brownsville Dam on the Calapooia River and the Savage Rapids Dam on the Rogue River. Within about one year after dam removal, the river ecology at both sites, as assessed by aquatic insect populations, was similar to the conditions upstream where there had been no dam impact.

Recovery of the physical structure of the river took a little longer. Following dam removal, some river pools downstream weren’t as deep as they used to be, some bars became thicker and larger, and the grain size of river beds changed. But those geomorphic changes diminished quickly as periodic floods flushed the river system, scientists said.

Within about two years, surveys indicated that the river was returning to the pre-removal structure, indicating that the impacts of the sediment released with dam removal were temporary and didn’t appear to do any long-term damage.

Instead, it was the presence of the dam that appeared to have the most persistent impact on the river biology and structure – what scientists call a “press” disturbance that will remain in place so long as the dam is there.

This press disturbance of dams can increase water temperatures, change sediment flow, and alter the types of fish, plants and insects that live in portions of rivers.  But the river also recovered rapidly from those impacts once the dam was gone.

It’s likely, the researchers said, that the rapid recovery found at these sites will mirror recovery on rivers with much larger dams, but more studies are needed.

For example, large scale and rapid changes are now taking place on the Elwha River in Washington state, following the largest dam removal project in the world. The ecological recovery there appears to be occurring rapidly as well. In 2014, Chinook salmon were observed in the area formerly occupied by one of the reservoirs, the first salmon to see that spot in 102 years.

“Disturbance is a natural river process,” Tullos said. “In the end, most of these large pulses of sediment aren’t that big of a deal, and there’s often no need to panic. The most surprising finding to us was that indicators of the biological recovery appeared to happen faster than our indicators of the physical recovery.”

The rates of recovery will vary across sites, though. Rivers with steeper gradients, more energetic flow patterns, and non-cohesive sediments will recover more quickly than flatter rivers with cohesive sediments, researchers said.

This research was supported by the Oregon Watershed Enhancement Board, the National Oceanic and Atmospheric Association and the National Marine Fisheries Service. It was a collaboration of researchers from the OSU College of Agricultural Sciences, College of Engineering, and College of Science.

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Desirée Tullos, 541-737-2038

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Dam removal

Removing Savage Rapids Dam

Lionfish characteristics make them more “terminator” than predator

SACRAMENTO, Calif. – New research on the predatory nature of red lionfish, the invasive Pacific Ocean species that is decimating native fish populations in parts of the Caribbean Sea and Atlantic Ocean, seems to indicate that lionfish are not just a predator, but more like the “terminator” of movie fame.

The finding of behavior that was called “alarming” was presented today by Kurt Ingeman, a researcher from Oregon State University, at the annual meeting of the Ecological Society of America.

Most native predatory fish are attracted to prey when their numbers are high, when successful attacks are easy and when a minimum of energy is needed to catch and eat other fish, according to previous research done by Michael Webster, a fish ecologist who received his doctorate from OSU. As the population of prey diminishes, the native predators often move on to other areas where, literally, the fishing is better.

The new research concludes that lionfish, by comparison, appear to stay in one area even as the numbers of prey diminish, and in some cases can eat the population to local extinction. They have unique characteristics that make this possible, and like the terminator, they simply will not stop until the last of their prey is dead.

“Lionfish seem to be the ultimate invader,” said Ingeman, a doctoral candidate in the Department of Integrative Biology within the OSU College of Science. “Almost every new thing we learn about them is some characteristic that makes them a more formidable predator. And it’s now clear they will hunt successfully even when only a few fish are present. This behavior is unusual and alarming.”

This research was conducted on replicated natural reefs in the Bahamas, measuring prey mortality of the fairy basslet – a popular aquarium fish and a common prey of lionfish.

Predation rates were compared between reefs with the invasive lionfish and reefs with native predators alone, and across a range of population levels of the fairy basslet. Ingeman found that when prey fish were present at a low population density, the rate of mortality with lionfish present was four times higher than that caused by native predators alone, such as medium-sized groupers or trumpet fish.

The findings are of some importance, researchers said, because fairy basslet live in small local populations, which are most vulnerable to local extinction. It also shows that the mechanisms that ordinarily regulate population size can be altered.

“Reef fish usually hide in rocks and crevices for protection, and with high populations, there is a scramble for shelter,” Ingeman said. “Native predators take advantage of this situation by mostly eating when and where prey are abundant. As prey population levels decline, it takes a lot more energy to catch fish, so the predators often move on to other areas.”

Because of this process that scientists call “density-dependent” predation, populations of native prey fish tend to shrink when they get too large, grow when they get too small, and are rarely ever wiped out completely.

Lionfish, however, have such advantages as an invasive species that they apparently feel no need to move on for better or easier hunting. They may not be recognized as a predator by other fish, leading to high mortality even when shelter is abundant. Lionfish are also very efficient hunters, are well-defended themselves by poisonous spines, and can thrive at deep levels in the ocean. They tolerate a wide range of habitats and water conditions, reproduce rapidly most of the year, eat many different species of native fish and may overeat rare species.

Still unclear, Ingeman said, is whether evolutionary pressures may allow native fish in the Atlantic Ocean to adapt new behaviors that provide better defense against lionfish.

“There’s a strong pressure here for natural selection to come into play eventually,” Ingeman said. “We know that fish can learn and change their behavior, sometimes over just a few generations. But we don’t have any studies yet to demonstrate this is taking place with native fish populations in the Atlantic.”

The lionfish invasion in the Atlantic Ocean is believed to have begun in the 1980s and now covers an area larger than the entirety of the United States. Ingeman’s adviser, Mark Hixon, and fellow graduate students have shown that lionfish can wipe out more than 90 percent of the native fish in some hard-hit areas.

The research was supported by the National Science Foundation and the Cape Eleuthera Institute of the Bahamas.

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Kurt Ingeman, 541-908-0805

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Fairy Basslet

Fairy basslet



Reef research

Reef research

Advantage Accelerator “graduates” moving toward successful new businesses, jobs

CORVALLIS, Ore. – Four promising startup companies in fields ranging from social media to chemical manufacturing are among the first “graduating class” of the Oregon State University Advantage Accelerator, upon completion of a program designed to help lead them toward commercial success.

Organizers of the new program say it’s off to a promising start in efforts to bring more university research and community ideas to the commercial marketplace. This and other elements of the OSU Advantage form partnerships with industry and work to boost the Oregon economy, while providing invaluable experiences for OSU students involved in many aspects of the program.

“Our program has unfolded as well or better than we had hoped, and we now plan to increase the output,” said John Turner, co-director of the Advantage Accelerator. “Completion of this program means that companies have an increased chance to succeed and have a step-by-step plan to approach the future.”

“Based on our experience in the first year of this program, we’ve decided to conduct two cohort groups each year rather than one,” Turner said. “The coming year will result in about 15-20 new startup companies.”

Success in a tough and competitive commercial marketplace is not automatic, however, and not all companies have the will and strength to complete the rigorous program.

The first graduates have completed a “portfolio” of accomplishments, Turner said, that included training to attract investors, a validated business model, a schedule for future steps, and an initial product to show prospective customers, investors or manufacturers. A few clients are already attracting attention through the sale of products and generating profit.

The OSU Advantage Accelerator provides mentoring with industry and entrepreneurial experts, consulting sessions, access to seed grants and the OSU Venture Fund, meetings with active investors, workshops on various topics, networking events and many other activities.

One of the early participants in the program, Onboard Dynamics of Bend, Ore., plans to market technology that could ultimately revolutionize the way America drives. It has developed systems that compress natural gas right in the vehicle and take advantage of the enormous current supplies of low-cost natural gas. The innovation is able to cut automobile fuel costs to the gasoline-equivalent of less than $1 a gallon.

“An intern working with the Advantage Accelerator performed a lot of tasks relating to market analysis and startup activities that were incredibly helpful to the company,” said CEO Rita Hansen.

“We’re in an excellent position right now, having been formally selected by the Department of Energy for a $2.88 million award, and our initial target markets are the underserved, small, light-duty commercial fleets,” Hansen said. “We’re very bullish about widespread adoption by these fleets of our products.”

A few other companies that have completed the program include:

  • Pikli, a student-based company based on social media that allows individuals to involve their friends and family in their shopping experiences;
  • Waste2Watergy, which is commercializing a microbial fuel cell technology to reduce or eliminate significant wastewater costs and produce electricity from the resultant effluence; and
  • Valliscor, a chemical manufacturing company that licensed technology developed at OSU to produce high-value chemicals for the pharmaceutical, agricultural, polymer and electronics industries.

“The OSU Advantage Accelerator program was very helpful and their mentorship was really first-rate,” said Rich Carter, professor and chair of the OSU Department of Chemistry, and CEO of Valliscor. “They helped us develop the necessary tools to become a functioning company, and whenever you needed advice all you had to do was pick up the phone.”

Carter said he’s “very optimistic” about the company going forward, which is already producing and selling its first products.

The OSU Advantage Accelerator is one component of the Oregon Regional Accelerator and Innovation Network, or Oregon RAIN. With support from the Oregon legislature, collaborators on the initiative include OSU, the University of Oregon, the cities of Eugene, Springfield, Corvallis and Albany, and other economic development organizations. All the participants are focused on creating new business, expanding existing business, creating jobs and helping to build the Oregon and national economy.

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John Turner, 541-368-5204

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New company

Valliscor research

Lipoic acid helps restore, synchronize the “biological clock”

CORVALLIS, Ore. – Researchers have discovered a possible explanation for the surprisingly large range of biological effects that are linked to a micronutrient called lipoic acid: It appears to reset and synchronize circadian rhythms, or the “biological clock” found in most life forms.

The ability of lipoic acid to help restore a more normal circadian rhythm to aging animals could explain its apparent value in so many important biological functions, ranging from stress resistance to cardiac function, hormonal balance, muscle performance, glucose metabolism and the aging process.

The findings were made by biochemists from the Linus Pauling Institute at Oregon State University, and published in Biochemical and Biophysical Research Communications, a professional journal. The research was supported by the National Institutes of Health, through the National Center for Complementary and Alternative Medicine.

Lipoic acid has been the focus in recent years of increasing research by scientists around the world, who continue to find previously unknown effects of this micronutrient. As an antioxidant and compound essential for aerobic metabolism, it’s found at higher levels in organ meats and leafy vegetables such as spinach and broccoli.

“This could be a breakthrough in our understanding of why lipoic acid is so important and how it functions,” said Tory Hagen, the Helen P. Rumbel Professor for Healthy Aging Research in the Linus Pauling Institute, and a professor of biochemistry and biophysics in the OSU College of Science.

“Circadian rhythms are day-night cycles that affect the daily ebb and flow of critical biological processes,” Hagen said. “The more we improve our understanding of them, the more we find them involved in so many aspects of life.”

Almost one-third of all genes are influenced by circadian rhythms, and when out of balance they can play roles in cancer, heart disease, inflammation, hormonal imbalance and many other areas, the OSU researchers said.

Of particular importance is the dysfunction of circadian rhythms with age.

“In old animals, including elderly humans, it’s well-known that circadian rhythms break down and certain enzymes don’t function as efficiently, or as well as they should,” said Dove Keith, a research associate in the Linus Pauling Institute and lead author on this study.

“This is very important, and probably deserves a great deal more study than it is getting,” Keith said. “If lipoic acid offers a way to help synchronize and restore circadian rhythms, it could be quite significant.”

In this case the scientists studied the “circadian clock” of the liver. Lipid metabolism by the liver is relevant to normal energy use, metabolism, and when dysfunctional can help contribute to the “metabolic syndrome” that puts millions of people at higher risk of heart disease, diabetes and cancer.

Researchers fed laboratory animals higher levels of lipoic acid than might be attained in a normal diet, while monitoring proteins known to be affected by disruption of the circadian clock in older animals.

They found that lipoic acid helped remediate some of the liver dysfunction that’s often common in old age, and significantly improved the function of their circadian rhythms.

In previous research, scientists found that the amount of lipoic acid that could aid liver and normal lipid function was the equivalent of about 600 milligrams daily for a 150-pound human, more than could normally be obtained through the diet.

A primary goal of research in the Linus Pauling Institute and the OSU Center for Healthy Aging Research is to promote what scientists call “healthspan” – not just the ability to live a long life, but to have comparatively good health and normal activities during almost all of one’s life. Research on lipoic acid, at OSU and elsewhere, suggests it has value toward that goal.

Continued research will explore this process and its role in circadian function, whether it can be sustained, and optimal intake levels that might be needed to improve health.

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Tory Hagen, 541-737-5083

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Shifting rhythms

Rhythms decline with age

New assay to spot fake malaria drugs could save thousands of lives

CORVALLIS, Ore. – Chemists and students in science and engineering at Oregon State University have created a new type of chemical test, or assay, that’s inexpensive, simple, and can tell whether or not one of the primary drugs being used to treat malaria is genuine – an enormous and deadly problem in the developing world.

The World Health Organization has estimated that about 200,000 lives a year may be lost due to the use of counterfeit anti-malarial drugs. When commercialized, the new OSU technology may be able to help address that problem by testing drugs for efficacy at a cost of a few cents.

When broadly implemented, this might save thousands of lives every year around the world, and similar technology could also be developed for other types of medications and diseases, experts say.

Findings on the new technology were just published in Talanta, a professional journal.

“There are laboratory methods to analyze medications such as this, but they often are not available or widely used in the developing world where malaria kills thousands of people every year,” said Vincent Remcho, a professor of chemistry and Patricia Valian Reser Faculty Scholar in the OSU College of Science, a position which helped support this work.

“What we need are inexpensive, accurate assays that can detect adulterated pharmaceuticals in the field, simple enough that anyone can use them,” Remcho said. “Our technology should provide that.”

The system created at OSU looks about as simple, and is almost as cheap, as a sheet of paper. But it’s actually a highly sophisticated “colorimetric” assay that consumers could use to tell whether or not they are getting the medication they paid for – artesunate - which is by far the most important drug used to treat serious cases of malaria. The assay also verifies that an adequate level of the drug is present.

In some places in the developing world, more than 80 percent of outlets are selling counterfeit pharmaceuticals, researchers have found. One survey found that 38-53 percent of outlets in Cambodia, Laos, Myanmar, Thailand and Vietnam had no active drug in the product that was being sold. Artesunate, which can cost $1 to $2 per adult treatment, is considered an expensive drug by the standards of the developing world, making counterfeit drugs profitable since the disease is so prevalent.

Besides allowing thousands of needless deaths, the spread of counterfeit drugs with sub-therapeutic levels of artesunate can promote the development of new strains of multi-drug resistant malaria, with global impacts. Government officials could also use the new system as a rapid screening tool to help combat the larger problem of drug counterfeiting.

The new technology is an application of microfluidics, in this instance paper microfluidics, in which a film is impressed onto paper that can then detect the presence and level of the artesunate drug. A single pill can be crushed, dissolved in water, and when a drop of the solution is placed on the paper, it turns yellow if the drug is present. The intensity of the color indicates the level of the drug, which can be compared to a simple color chart.

OSU undergraduate and graduate students in chemistry and computer science working on this project in the Remcho lab took the system a step further, and created an app for an iPhone that could be used to measure the color, and tell with an even higher degree of accuracy both the presence and level of the drug.

The technology is similar to what can be accomplished with computers and expensive laboratory equipment, but is much simpler and less expensive. As a result, use of this approach may significantly expand in medicine, scientists said.

“This is conceptually similar to what we do with integrated circuit chips in computers, but we’re pushing fluids around instead of electrons, to reveal chemical information that’s useful to us,” Remcho said.  “Chemical communication is how Mother Nature does it, and the long term applications of this approach really are mind-blowing.”

Colorimetric assays have already been developed for measurement of many biomarker targets of interest, Remcho said, and could be expanded for a wide range of other medical conditions, pharmaceutical and diagnostic tests, pathogen detection, environmental analysis and other uses.

With a proof of concept of the new technology complete, the researchers may work with the OSU Advantage to commercialize the technology, ultimately with global application. As an incubator for startup and early stage organizations, OSU Advantage connects business with faculty expertise and student talent to bring technology such as this to market.

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Vincent Remcho, 541-737-8181

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Paper assay

Drug assay

SAR11, oceans’ most abundant organism, has ability to create methane

CORVALLIS, Ore. – The oxygen-rich surface waters of the world’s major oceans are supersaturated with methane – a powerful greenhouse gas that is roughly 20 times more potent than carbon dioxide – yet little is known about the source of this methane.

Now a new study by researchers at Oregon State University demonstrates the ability of some strains of the oceans’ most abundant organism – SAR11 – to generate methane as a byproduct of breaking down a compound for its phosphorus.

Results of the study are being published this week in Nature Communications. It was funded by the National Science Foundation and the Gordon and Betty Moore Foundation.

“Anaerobic methane biogenesis was the only process known to produce methane in the oceans and that requires environments with very low levels of oxygen,” said Angelicque “Angel” White, a researcher in OSU’s College of Earth, Ocean, and Atmospheric Sciences and co-author on the study. “In the vast central gyres of the Pacific and Atlantic oceans, the surface waters have lots of oxygen from mixing with the atmosphere – and yet they also have lots of methane, hence the term ‘marine methane paradox.’

“We’ve now learned that certain strains of SAR11, when starved for phosphorus, turn to a compound known as methylphosphonic acid,” White added. “The organisms produce enzymes that can break this compound apart, freeing up phosphorus that can be used for growth – and leaving methane behind.”

The discovery is an important piece of the puzzle in understanding the Earth’s methane cycle, scientists say. It builds on a series of studies conducted by researchers from several institutions around the world over the past several years.

Previous research has shown that adding methylphosphonic acid, or MPn, to seawater produces methane, though no one knew exactly how. Then a laboratory study led by David Karl of the University of Hawaii and OSU’s White found that an organism called Trichodesmium could break down MPn and thus it could be a potential source of phosphorus, which is a critical mineral essential to every living organism.

However, Trichodesmium are rare in the marine environment and unlikely to be the only source for vast methane deposits in the surface waters.

So White turned to Steve Giovannoni, a distinguished professor of microbiology at OSU, who not only maintains the world’s largest bank of SAR11 strains, but who also discovered and identified SAR11 in 1990. In a series of experiments, White, Giovannoni, and graduate students Paul Carini and Emily Campbell tested the capacity of different SAR11 strains to consume MPn and cleave off methane.

“We found that some did produce a methane byproduct, and some didn’t,” White said. “Just as some humans have a different capacity for breaking down compounds for nutrition than others, so do these organisms. The bottom line is that this shows phosphate-starved bacterioplankton have the capability of producing methane and doing so in oxygen-rich waters.”

SAR11 is the smallest free-living cell known and also has the smallest genome, or genetic structure, of any independent cell. Yet it dominates life in the oceans, thrives where most other cells would die, and plays a huge role in the cycling of carbon on Earth.

These bacteria are so dominant that their combined weight exceeds that of all the fish in the world's oceans, scientists say. In a marine environment that's low in nutrients and other resources, they are able to survive and replicate in extraordinary numbers – a milliliter of seawater, for instance, might contain 500,000 of these cells.

"The ocean is a competitive environment and these bacteria apparently won the race," said Giovannoni, a professor in OSU’s College of Science. "Our analysis of the SAR11 genome indicates that they became the dominant life form in the oceans largely by being the simplest.”

“Their ability to cleave off methane is an interesting finding because it provides a partial explanation for why methane is so abundant in the high-oxygen waters of the mid-ocean regions,” Giovannoni added. “Just how much they contribute to the methane budget still needs to be determined.”

Since the discovery of SAR11, scientists have been interested in their role in the Earth’s carbon budget. Now their possible implication in methane creation gives the study of these bacteria new importance.

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Angel White, 541-737-6397; awhite@coas.oregonstate.edu; Steve Giovannoni, 541-737-1835, steve.giovannoni@oregonstate.edu

“Molecular movie” technology may enable big gains in bioimaging, health research

CORVALLIS, Ore. – Researchers today announced the creation of an imaging technology more powerful than anything that has existed before, and is fast enough to observe life processes as they actually happen at the molecular level.

Chemical and biological actions can now be measured as they are occurring or, in old-fashioned movie parlance, one frame at a time. This will allow creation of improved biosensors to study everything from nerve impulses to cancer metastasis as it occurs.

The measurements, created by the use of short pulse lasers and bioluminescent proteins, are made in femtoseconds, which is one-millionth of one-billionth of a second. A femtosecond, compared to one second, is about the same as one second compared to 32 million years.

That’s a pretty fast shutter speed, and it should change the way biological research and physical chemistry are being done, scientists say.

Findings on the new technology were published today in Proceedings of the National Academy of Sciences, by researchers from Oregon State University and the University of Alberta.

“With this technology we’re going to be able to slow down the observation of living processes and understand the exact sequences of biochemical reactions,” said Chong Fang, an assistant professor of chemistry in the OSU College of Science, and lead author on the research.

“We believe this is the first time ever that you can really see chemistry in action inside a biosensor,” he said. “This is a much more powerful tool to study, understand and tune biological processes.”

The system uses advanced pulse laser technology that is fairly new and builds upon the use of “green fluorescent proteins” that are popular in bioimaging and biomedicine. These remarkable proteins glow when light is shined upon them. Their discovery in 1962, and the applications that followed, were the basis for a Nobel Prize in 2008.

Existing biosensor systems, however, are created largely by random chance or trial and error. By comparison, the speed of the new approach will allow scientists to “see” what is happening at the molecular level and create whatever kind of sensor they want by rational design. This will improve the study of everything from cell metabolism to nerve impulses, how a flu virus infects a person, or how a malignant tumor spreads.

“For decades, to create the sensors we have now, people have been largely shooting in the dark,” Fang said. “This is a fundamental breakthrough in how to create biosensors for medical research from the bottom up. It’s like daylight has finally come.”

The technology, for instance, can follow the proton transfer associated with the movement of calcium ions – one of the most basic aspects of almost all living systems, and also one of the fastest. This movement of protons is integral to everything from respiration to cell metabolism and even plant photosynthesis.  Scientists will now be able to identify what is going on, one step at a time, and then use that knowledge to create customized biosensors for improved imaging of life processes.

“If you think of this in photographic terms,” Fang said, “we now have a camera fast enough to capture the molecular dance of life. We’re making molecular movies. And with this, we’re going to be able to create sensors that answer some important, new questions in biophysics, biochemistry, materials science and biomedical problems.”

The research was supported by OSU, the University of Alberta, the Natural Sciences and Engineering Research Council of Canada, and the Canadian Institutes of Health Research.

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Chong Fang, 541-737-6704

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Molecular movies

Molecular movies

Findings point toward one of first therapies for Lou Gehrig’s disease

CORVALLIS, Ore. – Researchers have determined that a copper compound known for decades may form the basis for a therapy for amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease.

In a new study just published in the Journal of Neuroscience, scientists from Australia, the United States (Oregon), and the United Kingdom showed in laboratory animal tests that oral intake of this compound significantly extended the lifespan and improved the locomotor function of transgenic mice that are genetically engineered to develop this debilitating and terminal disease.

In humans, no therapy for ALS has ever been discovered that could extend lifespan more than a few additional months. Researchers in the Linus Pauling Institute at Oregon State University say this approach has the potential to change that, and may have value against Parkinson’s disease as well.

“We believe that with further improvements, and following necessary human clinical trials for safety and efficacy, this could provide a valuable new therapy for ALS and perhaps Parkinson’s disease,” said Joseph Beckman, a distinguished professor of biochemistry and biophysics in the OSU College of Science.

“I’m very optimistic,” said Beckman, who received the 2012 Discovery Award from the OHSU Medical Research Foundation as the leading medical researcher in Oregon.

ALS was first identified as a progressive and fatal neurodegenerative disease in the late 1800s and gained international recognition in 1939 when it was diagnosed in American baseball legend Lou Gehrig. It’s known to be caused by motor neurons in the spinal cord deteriorating and dying, and has been traced to mutations in copper, zinc superoxide dismutase, or SOD1. Ordinarily, superoxide dismutase is an antioxidant whose proper function is essential to life.

When SOD1 is lacking its metal co-factors, it “unfolds” and becomes toxic, leading to the death of motor neurons. The metals copper and zinc are important in stabilizing this protein, and can help it remain folded more than 200 years.

“The damage from ALS is happening primarily in the spinal cord and that’s also one of the most difficult places in the body to absorb copper,” Beckman said. “Copper itself is necessary but can be toxic, so its levels are tightly controlled in the body. The therapy we’re working toward delivers copper selectively into the cells in the spinal cord that actually need it. Otherwise, the compound keeps copper inert.”

“This is a safe way to deliver a micronutrient like copper exactly where it is needed,” Beckman said.

By restoring a proper balance of copper into the brain and spinal cord, scientists believe they are stabilizing the superoxide dismutase in its mature form, while improving the function of mitochondria. This has already extended the lifespan of affected mice by 26 percent, and with continued research the scientists hope to achieve even more extension.

The compound that does this is called copper (ATSM), has been studied for use in some cancer treatments, and is relatively inexpensive to produce.

“In this case, the result was just the opposite of what one might have expected,” said Blaine Roberts, lead author on the study and a research fellow at the University of Melbourne, who received his doctorate at OSU working with Beckman.

“The treatment increased the amount of mutant SOD, and by accepted dogma this means the animals should get worse,” he said. “But in this case, they got a lot better. This is because we’re making a targeted delivery of copper just to the cells that need it.

“This study opens up a previously neglected avenue for new disease therapies, for ALS and other neurodegenerative disease,” Roberts said.

Other collaborators on this research include OSU, the University of Melbourne, University of Technology/Sydney, Deakin University, the Australian National University, and the University of Leeds in the United Kingdom.

Funding has been provided by the Australian National Health and Medical Research Council, the U.S. National Institutes of Health, the Linus Pauling Institute and other groups in Australia and Finland.

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Joseph Beckman, 541-737-8867