college of science

Increasing toxicity of algal blooms tied to nutrient enrichment and climate change

CORVALLIS, Ore. – Nutrient enrichment and climate change are posing yet another concern of growing importance – an apparent increase in the toxicity of some algal blooms in freshwater lakes and estuaries around the world, which threatens aquatic organisms, ecosystem health and human drinking water safety.

As this nutrient enrichment, or “eutrophication” increases, so will the proportion of toxin-producing strains of cyanobacteria in harmful algal blooms, scientists said.

Researchers from Oregon State University and the University of North Carolina at Chapel Hill will outline recent findings in an analysis Friday in the journal Science.

Cyanobacteria are some of the oldest microorganisms on Earth, dating back about 3.5 billion years to a time when the planet was void of oxygen and barren of most life. These bacteria are believed to have produced the oxygen that paved the way for terrestrial life to evolve. They are highly adaptive and persistent, researchers say, and today are once again adapting to new conditions in a way that threatens some of the life they originally made possible.

A particular concern is Microcystis sp., a near-ubiquitous cyanobacterium that thrives in warm, nutrient-rich and stagnant waters around the world. Like many cyanobacteria, it can regulate its position in the water column, and often forms green, paint-like scums near the surface.

In a high-light, oxidizing environment, microcystin-producing cyanobacteria have a survival advantage over other forms of cyanobacteria that are not toxic. Over time, they can displace the nontoxic strains, resulting in blooms that are increasingly toxic.

“Cyanobacteria are basically the cockroaches of the aquatic world,” said Timothy Otten, a postdoctoral scholar in the OSU College of Science and College of Agricultural Sciences, whose work has been supported by the National Science Foundation. “They're the uninvited guest that just won't leave.”

“When one considers their evolutionary history and the fact that they've persisted even through ice ages and asteroid strikes, it's not surprising they're extremely difficult to remove once they’ve taken hold in a lake,” he said. “For the most part, the best we can do is to try to minimize the conditions that favor their proliferation.”

Researchers lack an extensive historical record of bloom events and their associated toxicities to put current observations into a long-term context.  However, Otten said, “If you go looking for toxin-producing cyanobacteria, chances are you won't have to look very long until you find some.”

There are more than 123,000 lakes greater than 10 acres in size spread across the United States, and based on the last EPA National Lakes Assessment, at least one-third may contain toxin-producing cyanobacteria. Dams; rising temperatures and carbon dioxide concentrations; droughts; and increased runoff of nutrients from urban and agricultural lands are all compounding the problem.

Many large, eutrophic lakes such as Lake Erie are plagued each year by algal blooms so massive that they are visible from outer space. Dogs have died from drinking contaminated water.

Researchers studying cyanobacterial toxins say it’s improbable that their true function was to be toxic, since they actually predate any predators. New research suggests that the potent liver toxin and possible carcinogen, microcystin, has a protective role in cyanobacteria and helps them respond to oxidative stress. This is probably one of the reasons the genes involved in its biosynthesis are so widespread across cyanobacteria and have been retained over millions of years.

Because of their buoyancy and the location of toxins primarily within the cell, exposure risks are greatest near the water's surface, which raises concerns for swimming, boating and other recreational uses.

Also, since cyanobacteria blooms become entrenched and usually occur every summer in impacted systems, chronic exposure to drinking water containing these compounds is an important concern that needs more attention, Otten said.

“Water quality managers have a toolbox of options to mitigate cyanobacteria toxicity issues, assuming they are aware of the problem and compelled to act,” Otten said. “But there are no formal regulations in place on how to respond to bloom events.

“We need to increase public awareness of these issues,” he said. “With a warming climate, rising carbon dioxide levels, dams on many rivers and overloading of nutrients into our waterways, the magnitude and duration of toxic cyanobacterial blooms is only going to get worse.”

Media Contact: 

Tim Otten, 541-737-1796

Multimedia Downloads
Green wake

Green wake

Toxic bacteria

Toxic bacteria

Lake sample

Toxic algal bloom

Beyond antibiotics: “PPMOs” offer new approach to bacterial infection

CORVALLIS, Ore. – Researchers at Oregon State University and other institutions today announced the successful use of a new type of antibacterial agent called a PPMO, which appears to function as well or better than an antibiotic, but may be more precise and also solve problems with antibiotic resistance.

In animal studies, one form of PPMO showed significant control of two strains of Acinetobacter, a group of bacteria of global concern that has caused significant mortality among military personnel serving in Middle East combat.

The new PPMOs offer a fundamentally different attack on bacterial infection, researchers say.

They specifically target the underlying genes of a bacterium, whereas conventional antibiotics just disrupt its cellular function and often have broader, unwanted impacts. As they are further developed, PPMOs should offer a completely different and more precise approach to managing bacterial infection, or conceptually almost any disease that has an underlying genetic component.

The findings were published today in the Journal of Infectious Diseases, by researchers from OSU, the University of Texas Southwestern Medical Center, and Sarepta, Inc., a Corvallis, Ore., firm.

“The mechanism that PPMOs use to kill bacteria is revolutionary,” said Bruce Geller, a professor of microbiology in the OSU College of Science and lead author on the study. “They can be synthesized to target almost any gene, and in that way avoid the development of antibiotic resistance and the negative impacts sometimes associated with broad-spectrum antibiotics.

“Molecular medicine,” Geller said, “is the way of the future.”

PPMO stands for a peptide-conjugated phosphorodiamidate morpholino oligomer – a synthetic analog of DNA or RNA that has the ability to silence the expression of specific genes. Compared to conventional antibiotics, which are often found in nature, PPMOs are completely synthesized in the laboratory with a specific genetic target in mind.

In animal laboratory tests against A. baumannii, one of the most dangerous Acinetobacter strains, PPMOs were far more powerful than some conventional antibiotics like ampicillin, and comparable to the strongest antibiotics available today. They were also effective in cases where the bacteria were resistant to antibiotics.

PPMOs have not yet been tested in humans. However, their basic chemical structure, the PMO, has been extensively tested in humans and found safe. Although the addition of the peptide to the PPMO poses an uncertain risk of toxicity, the potency of PPMOs reduces the risk while greatly improving delivery of the PMOs into bacterial cells, Geller said.

Geller said research is being done with Acinetobacter in part because this pathogen has become a huge global problem, and is often spread in hospitals. It can cause respiratory infection, sepsis, and is a special concern to anyone whose immune system is compromised. Wounds in military battle conditions have led to numerous cases in veterans, and A. baumannii is now resistant to many antibiotics. “Urgent new approaches to therapeutics are needed,” the scientists said in their report.

Continued research and eventually human clinical trials will be required before the new compounds are available for health care, the researchers said. This and continued studies have been supported by the National Institutes of Health, the other collaborators and the N.L. Tartar fund.


Editor’s Note: A scanning electron microscope image of A. baumannii is available online (please provide image credit as indicated at web site): http://bit.ly/GztejR

Media Contact: 

Bruce Geller, 541-737-1845

Red grapes, blueberries may enhance immune function

CORVALLIS, Ore. – In an analysis of 446 compounds for their the ability to boost the innate immune system in humans, researchers in the Linus Pauling Institute at Oregon State University discovered just two that stood out from the crowd – the resveratrol found in red grapes and a compound called pterostilbene from blueberries.

Both of these compounds, which are called stilbenoids, worked in synergy with vitamin D and had a significant impact in raising the expression of the human cathelicidin antimicrobial peptide, or CAMP gene, that is involved in immune function.

The findings were made in laboratory cell cultures and do not prove that similar results would occur as a result of dietary intake, the scientists said, but do add more interest to the potential of some foods to improve the immune response.

The research was published today in Molecular Nutrition and Food Research, in studies supported by the National Institutes of Health.

“Out of a study of hundreds of compounds, just these two popped right out,” said Adrian Gombart, an LPI principal investigator and associate professor in the OSU College of Science. “Their synergy with vitamin D to increase CAMP gene expression was significant and intriguing. It’s a pretty interesting interaction.”

Resveratrol has been the subject of dozens of studies for a range of possible benefits, from improving cardiovascular health to fighting cancer and reducing inflammation. This research is the first to show a clear synergy with vitamin D that increased CAMP expression by several times, scientists said.

The CAMP gene itself is also the subject of much study, as it has been shown to play a key role in the “innate” immune system, or the body’s first line of defense and ability to combat bacterial infection. The innate immune response is especially important as many antibiotics increasingly lose their effectiveness.

A strong link has been established between adequate vitamin D levels and the function of the CAMP gene, and the new research suggests that certain other compounds may play a role as well.

Stilbenoids are compounds produced by plants to fight infections, and in human biology appear to affect some of the signaling pathways that allow vitamin D to do its job, researchers said. It appears that combining these compounds with vitamin D has considerably more biological impact than any of them would separately.

Continued research could lead to a better understanding of how diet and nutrition affect immune function, and possibly lead to the development of therapeutically useful natural compounds that could boost the innate immune response, the researchers said in their report.

Despite the interest in compounds such as resveratrol and pterostilbene, their bioavailability remains a question, the researchers said. Some applications that may evolve could be with topical use to improve barrier defense in wounds or infections, they said.

The regulation of the CAMP gene by vitamin D was discovered by Gombart, and researchers are still learning more about how it and other compounds affect immune function. The unique biological pathways involved are found in only two groups of animals – humans and non-human primates. Their importance in the immune response could be one reason those pathways have survived through millions of years of separate evolution of these species.

Media Contact: 

Adrian Gombart, 541-737-8018

Multimedia Downloads




Red grapes

Viruses associated with coral epidemic of “white plague”

CORVALLIS, Ore. – They call it the “white plague,” and like its black counterpart from the Middle Ages, it conjures up visions of catastrophic death, with a cause that was at first uncertain even as it led to widespread destruction – on marine corals in the Caribbean Sea.

Now one of the possible causes of this growing disease epidemic has been identified – a group of viruses that are known as small, circular, single-strand DNA (or SCSD) viruses. Researchers in the College of Science at Oregon State University say these SCSD viruses are associated with a dramatic increase in the white plague that has erupted in recent decades.

Prior to this, it had been believed that the white plague was caused primarily by bacterial pathogens. Researchers are anxious to learn more about this disease and possible ways to prevent it, because its impact on coral reef health has exploded.

“Twenty years ago you had to look pretty hard to find any occurrences of this disease, and now it’s everywhere,” said Nitzan Soffer, a doctoral student in the Department of Microbiology at OSU and lead author on a new study just published in the International Society for Microbial Ecology. “It moves fast and can wipe out a small coral colony in a few days.

“In recent years the white plague has killed 70-80 percent of some coral reefs,” Soffer said. “There are 20 or more unknown pathogens that affect corals and in the past we’ve too-often overlooked the role of viruses, which sometimes can spread very fast.”

This is one of the first studies to show viral association with a severe disease epidemic, scientists said. It was supported by the National Science Foundation.

Marine wildlife diseases are increasing in prevalence, the researchers pointed out. Reports of non-bleaching coral disease have increased more than 50 times since 1965, and are contributing to declines in coral abundance and cover.

White plague is one of the worst. It causes rapid tissue loss, affects many species of coral, and can cause partial or total colony mortality. Some, but not all types are associated with bacteria. Now it appears that viruses also play a role. Corals with white plague disease have higher viral diversity than their healthy counterparts, the study concluded.

Increasing temperatures that stress corals and make them more vulnerable may be part of the equation, because the disease often appears to be at its worst by the end of summer. Overfishing that allows more algae to grow on corals may help spread pathogens, researchers said, as can pollution caused by sewage outflows in some marine habitats.

Viral infection, by itself, does not necessarily cause major problems, the researchers noted. Many healthy corals are infected with herpes-like viruses that are persistent but not fatal, as in many other vertebrate hosts, including humans.

Media Contact: 
Multimedia Downloads
Coral disease

Coral with white plague

Marine research

Taking samples

Debut of new pale ale to assist research on sea star wasting disease

NEWPORT, Ore. – Oregon State University and the Partnership for Interdisciplinary Studies of Coastal Oceans, or PISCO, have a new ally in their efforts to study and address sea star wasting disease, a serious epidemic that has hit the North American West Coast.

This partner is reported to be light and crisp, with a red or purplish hue and a unique flavor that comes from the purple corn nectar used to brew it. It’s sold in a tall, 22-ounce bottle, and best served cold.

As part of a larger effort to learn more about the deadly disease that has devastated sea stars in some places on the Oregon coast, a craft brewery in Newport, Ore., has announced the sale of Wasted Sea Star Purple Pale Ale. Rogue Ales and Spirits today will hold a celebration that includes a beer christening and discussion about this disease outbreak.

The Rogue Ale brewers, who are concerned about this disease in Oregon coastal waters, plan to donate a portion of the income from sales of this product to support research done by OSU and PISCO scientists.  More information on Rogue Ales and Spirits’ new ale is available online at www.rogue.com/roguenews

“We are extremely excited about this new partnership with Rogue to raise awareness about the importance of sea stars to healthy ocean ecosystems,” said Bruce Menge, the lead PISCO-OSU investigator. “Rogue’s new beer also recognizes the efforts of investigators across the country who are collaborating to understand this disease and its impacts.”

Kristen Milligan, PISCO program coordinator, said, “This is an excellent example of an industry-academia partnership that can help educate, at the same time as helping to support the necessary science.”

Last year there was an unprecedented outbreak of sea star wasting disease on the Oregon coast, causing sea stars to lose arms, disintegrate and die over the course of a week or less. Today in Oregon, adult ochre star populations in the rocky intertidal zone are down dramatically from a year ago - anywhere from 30-80 percent less, depending on the location.

Researchers are carefully monitoring the survival of young sea stars, which are appearing at most locations along the coast in great numbers and offer some hope for population recovery.

Sea stars are an important part of marine ecosystems, in part because they attack mussels and keep their populations under control. Without enough sea stars, mussel populations can expand and grow over algae and other small invertebrates. The very concept of a “keystone predator” came from work in 1969 that used the purple ochre sea star as a model.

OSU researchers and students are working both to monitor and address this problem, in collaboration with a number of Oregon public and private agencies, and their PISCO partners at the University of California/Santa Cruz, UC/Santa Barbara, and Stanford University.

Media Contact: 

Kristen Milligan, 541-737-8862

Multimedia Downloads
Dying sea star
Dying sea star

Wasted Sea Star Purple Pale Ale
Ale label

The art and science of color to be topic at Corvallis Science Pub

CORVALLIS, Ore. – From art to clothes to entertainment, color shapes modern life. At the Corvallis Science Pub on Monday, April 6, Oregon State University chemist Mas Subramanian will present the art and science of color as it has affected culture and even generated economic opportunity.

Subramanian’s lab discovered a brilliant blue pigment in 2009 and has continued to develop applications with artists, paint manufacturers and other companies. In addition to blue, his lab has developed purples, greens and oranges with durable, environmentally beneficial qualities.

Subramanian will describe the chemical and physical origins of color in pigments and light. He’ll span the uses of colors in nature such as geology (gems and metals), biology (butterflies, peacock, hummingbirds, flamingos, eyes) and botany (plants, flowers, berries), and explain the origin of color in pigments used in art and industry.

The Science Pub presentation is free and open to the public. It begins at 6 p.m. at the Old World Deli, 341 S.W. 2nd St. in Corvallis. Sponsors of Science Pub include Terra magazine at OSU, the Downtown Corvallis Association and the Oregon Museum of Science and Industry.

Media Contact: 

Mas Subramanian, 541-737-8235

Multimedia Downloads

Mas Subramanian

Mas Subramanian

OSU marine ecologist to share Tyler Prize for environmental achievements

LOS ANGELES – Jane Lubchenco, the University Distinguished Professor of Marine Biology at Oregon State University, today was named as one of two recipients of the 2015 Tyler Prize for Environmental Achievement, a prestigious award made for leadership in conservation and sustainability policies.

The award includes a gold medallion and $200,000 cash prize, which will be shared by Lubchenco and the other award recipient, Madhav Gadgil, a forestry and environmental leader at Goa University in India.

Since its inception in 1973 as one of the world’s first international environmental awards, the Tyler Prize has been the premier award for environmental science, environmental health and energy.

“Drs. Lubchenco and Gadgil represent the very best in bringing high-quality science to policymaking, to protect our environment and ensure the sustainability of natural resources in their respective countries and around the world,” said Owen T. Lind, chair of the Tyler Prize executive committee.

“Both of these laureates have bridged science with cultural and economic realities – like the impact on indigenous peoples in India or fishing communities in the United States – to advance the best possible conservation policies,” Lind said.

Lubchenco has served as administrator of the National Oceanic and Atmospheric Administration, and was recently named the first-ever U.S. Science Envoy for the Oceans by the U.S. Department of State. She is also a past-president of the American Association for the Advancement of Science, and has helped launch several programs to train scientists to engage more effectively with non-scientists.

“When I started my career, I was almost entirely focused on how ocean ecosystems work and the cool discovery part of science,” Lubchenco said. “Why do species live one place and not another? What are the dynamics between species, such as predators and their prey? But over time, I saw the ocean was changing, sometimes very dramatically, and nobody was paying attention.”

Many of those changes have now been linked to human causes, including overfishing, ocean acidification, invasive species and other disruptions. At NOAA, Lubchenco helped implement the “catch share” model that works with local communities and gives fishermen more of a stake in the future, and has helped restore healthy fisheries in several regions.

“Long term economic prosperity depends on a healthy ocean,” she said. “Policy changes that align conservation and economic incentives can have powerful outcomes.”

In her new role as a science envoy, Lubchenco will have a mandate to promote this focus on ocean science, marine ecology, climate change and smart policy to a global audience.

“This State Department position gives me a terrific platform to share what works in protecting and restoring the ocean and to promote more, and better, science to inform how we use fisheries and the other resources of the ocean,” Lubchenco said.

The Tyler Prize, established by John and Alice Tyler, is awarded annually, with administrative support from the University of Southern California. On April 23 at 2 p.m., Lubchenco and Gadgil will deliver public lectures on their work at The Forum at USC.

Media Contact: 

Nick Seaver, 301-280-5727

Multimedia Downloads
Jane Lubchenco
Jane Lubchenco

Starfish wasting disease focus of Corvallis Science Pub

CORVALLIS, Ore. – In less than a week, a healthy sea star can develop dark lesions, lose its arms and disintegrate into mush. The unprecedented die-off of these animals along the Oregon coast in 2014 took scientists by surprise.

At the Feb. 9 Corvallis Science Pub, Oregon State University’s Bruce Menge will discuss efforts to understand the likely causes and potential consequences of this disease.

Menge leads a multiyear research program known as the Partnership for Interdisciplinary Studies of Coastal Oceans, or PISCO. As he and his colleagues investigated waters in Yaquina Bay, Boiler Bay and other locations, they documented the progress of the disease. They had never seen such rapid disappearance of what scientists call a keystone species – an animal that exerts a strong influence over the structure of an ecosystem.

From Alaska to Baja, California, the disease has affected more than 20 species of sea stars and attracted the attention of scientists across the country. In November, researchers at Cornell University and the University of California, Santa Cruz, announced that they had isolated a virus that appeared to be the cause of wasting, but the factors making the sea stars susceptible to disease remain unclear.

Menge is the Wayne and Gladys Valley Professor of Marine Biology and an OSU distinguished professor in the OSU College of Science.

The Science Pub presentation is free and open to the public. It begins at 6 p.m. at the Old World Deli, 341 S.W. 2nd St. in Corvallis. Sponsors of Science Pub include Terra magazine at OSU, the Downtown Corvallis Association and the Oregon Museum of Science and Industry.


Media Contact: 

Bruce Menge, 541-737-5358

OSU names Karplus, Lewis as 2015 Distinguished Professors

CORVALLIS, Ore. – Oregon State University has named Andrew Karplus and Jon Lewis as its 2015 Distinguished Professor recipients – the highest honor the university can give to faculty members.

They will carry the title as long as they are actively engaged as faculty members  at Oregon State.

“Andy Karplus and Jon Lewis exemplify excellence, collaboration and leadership,” said Sabah Randhawa, OSU provost and executive vice president. “In addition to making significant contributions in their respective fields, they are constantly engaging and challenging students and providing them with experiential learning opportunities. They also are caring mentors – to newer faculty as well as students.”

Karplus is a professor in the College of Science, where he has earned a reputation as one of the best structural biologists in the world – a description cited in his selection as a fellow of the American Association for the Advancement of Science in 2014. His research, which focuses on enzyme catalysis, protein evolution and structure, and crystallography, has been cited more than 15,000 times by other scientists.

He is known for his high standards in teaching, yet consistently gets top ratings from student evaluators. Karplus teaches a range of courses, from core offerings in the Department of Biochemistry and Biophysics, to a course on protein evolution – his department’s most influential advanced elective.

Karplus also has been praised for his work as an academic adviser, research mentor and collaborator.

An OSU faculty member since 1999, Karplus has received numerous awards include a National Research Service Award from the National Institutes of Health, three Alexander von Humboldt fellowships, and a Guggenheim Fellowship.

Lewis is a professor in the College of Liberal Arts who has written a dozen books on film studies, including two new books coming out this summer. He also is the editor of a ground-breaking 10-volume series of academic books on the history of the U.S. film craft that was underwritten by the Academy of Motion Picture Arts and Sciences.

He has been editor and advisory board member for the field’s leading peer-reviewed academic journal – the Cinema Journal – and has served as a juror for the American Academy of Motion Pictures Arts and Sciences in the student film category. Lewis excels at taking students behind the scenes of the film industry and was executive producer for a video production series on major figures in the U.S. industry.

An OSU faculty member since 1983, Lewis has received numerous awards for his books, including the New York Times New and Noteworthy Paperback for “Hollywood v. Hard Core”; the Booklist Medal for “For Whom God Wishes to Destroy” and the Choice Outstanding Academic Book Award for “Romance and Ruin.”

Both professors will give public lectures on campus this May 21 on topics related to their expertise.

Media Contact: 

Sabah Randhawa, 541-737-2111; sabah.randhawa@oregonstate.edu

Lubchenco receives World Academy of Sciences Medal

MUSCAT, Oman - Jane Lubchenco, the University Distinguished Professor and Advisor in Marine Studies at Oregon State University and former NOAA administrator, yesterday received The World Academy of Sciences Medal at the annual meeting of this organization in Muscat, Sultanate of Oman.

This international academy of sciences was founded by Abdus Salam, a physicist and Pakistani Nobel laureate, and the medal recognizes outstanding achievements in science. The organization, with about 1,100 members, promotes science and the development of scientific capacity in the developing world.

Lubchenco was first elected a member of the group in 2004, in recognition of her discoveries in marine ecology and efforts to strengthen science in the developing world. She served three years as president of the International Council for Science, a non-governmental organization that is the voice for international, interdisciplinary science.

Lubchenco presented an award lecture in Oman on Oct. 26 on “Delivering on Science’s Social Contract,” which will outline new advances that are transforming attitudes, behavior, management and policies that affect ocean health.

Lubchenco is an environmental scientist and marine ecologist whose research interests include biodiversity, climate change, sustainable use of oceans and the planet, and interactions between the environment and human well-being. She currently is a distinguished professor in the OSU College of Science and advisor in marine studies at OSU, and recently served for four years as the administrator for the National Oceanic and Atmospheric Administration.

Media Contact: 

Jane Lubchenco, 541-737-5337

Multimedia Downloads
Jane Lubchenco

Jane Lubchenco