Categories
Disease Faculty Spotlight News Research

Linsey Marr shares airborne virus knowledge, COVID-19 tips during virtual conversation

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VT News | September 15, 2020

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Throughout much of her career, Linsey Marr found that her multi-disciplinary approach to science was more of a challenge than an asset.

“For the past 12 years I feel like I’ve toiled in total obscurity working on airborne viruses,” said Marr, the Charles P. Lunsford Professor of Civil and Environmental Engineering. “It’s an interdisciplinary topic that doesn’t fall neatly into one department or field of study. I’ve struggled at times to get funding and to get papers — except now over the period of a couple of months, it became one of the hottest topics around.”

When the COVID-19 pandemic erupted across the world, and as scientists collected evidence that the virus was transmitted through airborne aerosols, that “total obscurity” suddenly became a bright spotlight. As one of fewer than 12 worldwide experts on aerosol transmission of viruses, and one of only a few in America, Marr’s expertise and ability to communicate to the public became a hot commodity. Since March, she has given more than 300 interviews and been quoted more than 4,000 times in 79 countries.

 

 

“Most of us had never heard of aerosol science before the pandemic,” began a New York Times profile headlined, “The Scientist, the Air and the Virus.” “Then Virginia Tech’s Linsey Marr showed up and became our tour guide to the invisible world of airborne particles.”

“It’s been a bit of a spaceship ride,” Marr laughed in an hour-long conversation with Virginia Tech President Tim Sands on Tuesday.

Marr’s interdisciplinary background gives her a broad view of the COVID-19 pandemic, but also the ability to communicate knowledge through memorable analogies and visuals that help her students and the public to better understand the virus and how it moves through the air.

As Sands noted, Marr took an interdisciplinary approach from the beginning of her academic career, “and even broadened rather than narrowed down as you went forward.”

“I hated the idea of having to choose a major,” Marr said. “I loved and appreciated natural science and math and even social science. I tried to pick a major that was as broad as possible.”

Marr holds a B.S. in Engineering Science from Harvard College and a Ph.D. in Civil and Environmental Engineering from the University of California at Berkeley. At Virginia Tech, she leads the Applied Interdisciplinary Research in Air (AIR2) laboratory and teaches courses on air pollution and environmental engineering.

“Virginia Tech has a strong culture of promoting interdisciplinary research,” Marr said. “I felt free to pursue research that was interesting to me. I have great colleagues here. The culture of the university allows you to reach across departments. People are very friendly and open to collaboration. People aren’t trying to protect their turf as much.”

As COVID-19 emerged in Wuhan, China, and began to spread around the world, scientists debated how the virus was transmitted. Given her previous research on the spread of the flu and other diseases, as well as evidence that previous coronaviruses such as SARS spread through aerosols, Marr felt that COVID-19 would spread through aerosols as well.

In early March, Marr posted a thread on Twitter that began, “Let’s talk about #airborne transmission of #SARSCOV2 and other viruses. A discussion is needed to improve accuracy and reduce fear associated with the term.”

Marr told Sands she had posted that thread to bust some myths about airborne viruses and to replace them with more accurate information.

“As soon as people hear ‘airborne virus,’ there’s a tendency to panic,” Marr said. “I knew it was important to get the right information out there. We do know how this moves and there are things we can do to reduce transmission.”

The thread showcased Marr’s ability to communicate simply and effectively, and soon journalists came calling. She became an important voice in the public discourse. Marr used memorable images, describing large water droplets that are expelled by the mouth or nose as “cannonballs.” She compared the airborne transmission of the virus through clouds of microscopic droplets to being with a smoker: If one is indoors and the room is poorly ventilated, the smoke gets pretty thick, whereas if you’re in a car with the windows down, it’s not as bad.

Through the conversation, Sands leveraged Marr’s knowledge and descriptions to essentially walk through a how-to guide for students and the public to navigate this pandemic.

How to wear a mask:

Cover your nose and mouth, with no gaps around the edges.

How do masks work?

Marr described a horse and forest.

“What I like to think about is horse running full speed across a field, and at the edge of the field there’s a forest,” Marr said. “The trees are spaced closely, but they’re far enough apart that if the horse were moving slowly, the horse could get navigate through that forest. But the horse is going full speed, and it hits that the edge of the forest and it’s going to crash into the trees.

So that’s one way that the fibers in your mask trap particles that are coming at them. They [the particles] can’t make the turns that the airflow has to make around those fibers.”

Research shows that layering fabric improves a mask’s effectiveness. A single layer of fabric helps some, but two layers should block 95 percent of particles, Marr said.

How to gauge risk:

Remember the three Cs and the M.

  1. Avoid Close contact situations. Maintain distance from other people. Six feet doesn’t mark a magic barrier, but the particles do dilute with distance.
  2. Avoid Crowds. Being in large crowds increase the chances that one will be around someone infected with the virus, and that the virus will spread to others.
  3. Avoid Closed, poorly ventilated spaces. Imagine a cigarette smoker. In this room, will I take in any smoke?
  4. Wear Masks.

How to ride in a car:

Roll the windows down, even a few inches, and the air refreshes in a minute or two.

How to ride in an airplane:

The ventilation systems really help and are a point of pride for airlines. However, keep your mask on to reduce the risk of transmission from people in the row with you, in front of, and behind you.

How to socialize when it gets colder:

Marr suggested using blankets to tolerate cold temperatures outside, or indoors when all the windows are open. Another possibility for socializing outside would be to gather around a fire, if everyone is masked and keeping distance.

How to endure flu season:

Marr is optimistic.

“All the interventions that we’re taking for COVID-19 will also be effective for the flu, and so I expect we’ll see one of our mildest flu seasons ever,” Marr said. “The flu transmits largely in the in the same ways that COVID-19 transmits. There’s really a lot similarities, and I think we’ll see a lot fewer flus and other respiratory diseases this coming winter. But we need to remain vigilant.”

How to drink a beverage while wearing a mask:

Marr said she’d considered this at some length. Removing one’s mask to drink doesn’t really work. So she landed on the idea of combining a mask with a bendy straw — though Marr acknowledged with a laugh she hasn’t really tested this idea, either.

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CONTACT:

Suzanne Irby

Michael Stowe
540-392-4218

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Categories
Announcements Disease Global Change Research

Researchers co-located to Steger Hall at the FLSI to tackle infectious diseases and rapid environmental change

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VT News | August 27 2020

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The COVID-19 pandemic has shined a spotlight on the importance of bringing together innovative scientific minds to tackle infectious diseases and the need to forecast future threats at the human-environment interface.

The Fralin Life Sciences Institute is co-locating researchers from across three colleges at Virginia Tech to Steger Hall to make an impact at the interface of infectious disease and the environment.

“We are building upon the launch of our newly formed Center for Emerging, Zoonotic, and Arthropod-borne Pathogens and Fralin’s existing centers to support synergies among faculty who are working to tackle some of the grand life-science challenges of our time and improve the human condition. We are excited to have an impact on the community and to develop new leaders at the intersection of environmental changes and infectious disease, while building on our strengths in computational modeling and data analysis,” said Matt Hulver, executive director of the Fralin Life Sciences Institute.

A group of Virginia Tech professors who focus on vector-borne disease, disease ecology, pathogen transmission, ecological forecasting, and data analysis and computational modeling have just moved their research programs to Steger Hall and are looking forward to collaborating:

Clément Vinauger, assistant professor, biochemistry, College of Agriculture and Life Sciences. The Vinauger lab aims to understand the mechanisms that allow blood-feeding insects to be efficient disease vectors and identify and characterize factors that modulate their host-seeking behavior with the goal of developing new modes of mosquito control. The Vinauger lab leverages interdisciplinary tools to study the genetic and neural basis of mosquito behavior by combining methods from biochemistry, neuroscience, engineering, and chemical ecology.

Chloé Lahondère, assistant professor, biochemistry, College of Agriculture and Life Sciences. The Lahondère lab studies the effects of temperature and climate change on the eco-physiology and behavior of mosquitoes, kissing bugs, and tsetse flies. Her lab also has an interest in sugar feeding behavior in mosquitoes as well as in monitoring pathogens in local mosquito populations. The main goal is to better understand the ecology and biology of disease vector arthropods to develop new control tools using a multidisciplinary approach involving genetics, behavioral analyses, and field observations. These tools can be exploited to control mosquito populations and reduce the spread of disease.

Kate Langwig, assistant professor, biological sciences, College of Science. Langwig is a quantitative field ecologist, and uses mathematical models parameterized by field and experimental data to provide insights at the host-pathogen-environment interface. Langwig’s research program focuses on the role of disease in determining population dynamics and community structure. As part of this research, she explores how variation among hosts influences epidemiological dynamics, population impacts, and the effectiveness of vaccines. Langwig’s lab also studies the impact of infectious disease on ecological communities, the importance of disease in determining species extinctions, and the long-term persistence of populations affected by invasive pathogens.

Joseph Hoyt, assistant professor, biological sciences, College of Science. Hoyt’s research interests lie at the intersection of disease ecology and conservation biology. His lab works on basic and applied research questions, primarily in emerging infectious diseases of wildlife. His current research program is focused on understanding how pathogens are transmitted through multi-host communities, spanning individual to landscape scales. He is particularly interested in disentangling the relative importance of environmental transmission and free-living pathogen stages to help facilitate the control of future disease outbreaks and provide a deeper ecological understanding of infectious diseases.

Brandon Jutras, assistant professor, biochemistry, College of Agriculture and Life Sciences. Lyme disease is now the most reported vector-borne disease in the United States. In Virginia, it is estimated that the incidence has increased more than 6,000 percent in the past 10 years. Four major species of ticks can transmit the bacteria that causes Lyme disease, but only one of them, the blacklegged, or deer tick (Ixodes scapularis), is found in Virginia. The Jutras lab is using cutting-edge quantitative microscopy and molecular techniques to discover new targets for the diagnosis and treatment of Lyme disease. In addition, the Jutras lab is studying closely-related bacteria that cause syphilis, tickborne relapsing fever, and leptospirosis.

Dana Hawley, professor, biological sciences, College of Science. Pathogens are colonizing novel host populations with increasing frequency, underscoring the need to understand what factors drive infectious disease spread and the evolution of more harmful pathogens. The Hawley lab investigates the ecological and evolutionary mechanisms that underlie host susceptibility, pathogen virulence (i.e., the amount of harm that pathogens cause their hosts), and infectious disease transmission. The Hawley lab approaches disease ecology from a multi-disciplinary perspective to understand how individual physiology and pathogen characteristics, such as virulence, social behavior, and environmental context, interact to influence infectious disease dynamics. Ultimately, these studies will improve the understanding of the broader processes that underlie pathogen evolution and spread in wild animal, domestic animal, and human populations.

“Infectious diseases don’t follow disciplinary boundaries – their spread results from the convergence of molecular interactions within cells and tissues and ecological interactions between organisms and with their environment. We really have to break out of our departmental silos to effectively study the complexity of infectious disease emergence and spread,” said Hawley.

The Global Change Center, an arm of the Fralin Life Sciences Institute, is also moving and will be administratively housed in Steger Hall.

“Big problems require innovative collaborations and bold strategies to find solutions. Co-locating faculty from different colleges working on some of the most ‘wicked’ societal challenges of our time, will generate new collaborations, foster interdisciplinary student training, and promote efficiency. I am excited to make the move and help support the vibrant community in Steger Hall,” said William Hopkins, associate executive director of the Fralin Life Sciences Institute and director of the Global Change Center.

Hopkins’ research program at Virginia Tech, which focuses on physiological ecology, conservation, and wildlife ecotoxicology, will also be moving to Steger Hall.

“The Fralin Life Sciences Institute is removing barriers, both physical and disciplinary, and is positioning our faculty to advance Virginia Tech’s work in infectious diseases and its impact on a global community,” said Cyril Clarke, executive vice president and provost of Virginia Tech. “Working together across a range of disciplinary interests, I anticipate that new ways of thinking about the linkages between human, animal, and environmental health will better prepare us to manage pandemics such as COVID-19.”

A group of scientists with cutting-edge skills in data analysis, computer modeling, and ecological forecasting are also joining Steger Hall to tackle multiple problem spaces including those related to global change:

Leah Johnson, associate professor, statistics, College of Science. Johnson is a statistical ecologist working at the intersection of statistics, mathematics, and biology. She focuses on understanding how differences between individuals in a population result from external heterogeneity and stochasticity, and how this variability influences population level patterns, especially in the space of infectious disease epidemiology. She leads the Quantitative Ecological Dynamics Lab (QED Lab). The lab currently focuses on understanding how climate impacts transmission of vector-borne diseases, and how to predict changes in where disease is likely to be transmitted as climate changes. She also examines how environment and human changes to the landscape can impact energetics, foraging behavior, and population dynamics of animals. Her approach is to use theoretical models to understand how systems behave generally, while simultaneously seeking to confront and validate models with data and make predictions. Thus, a significant portion of her research focuses on methods for statistical — particularly Bayesian — inference and validation for mechanistic mathematical models of biological and ecological systems.

Lauren Childs, assistant professor, mathematics, College of Science. Childs develops and analyzes mathematical and computational models to examine biologically motivated questions. A main focus of her research program is understanding the pathogenesis and spread of infectious diseases, such as malaria and dengue. There is an emphasis on the interactions within an organism, such as between an invading pathogen and the host immune response. In addition, she also examines how these within-host interactions impact transmission of disease throughout a population. Construction and analysis of the models utilizes mathematics ranging from differential equations, dynamical systems, to stochastic analysis.

Luis Escobar, assistant professor, fish and wildlife conservation, College of Natural Resources and Environment. Ongoing global change projects in the Escobar lab include the role of aquatic and terrestrial invasive species in disease transmission, effects of climate change on the burden of vector-borne and water-borne diseases, and the development of analytical methods to assess the impacts of global change on biodiversity and diseases. Escobar’s lab focuses on the distribution of biodiversity, including parasites and pathogens at global scales, and under past, current, and future environmental conditions. Escobar is particularly interested in the use of ecoinformatics to study infectious diseases of fish and wildlife origin.

Quinn Thomas, associate professor, forest resources and environmental conservation, College of Natural Resources and Environment. Thomas’ research group studies the forest and freshwater ecosystems upon which society depends. They use quantitative models to simulate how ecosystems change over time in response to land-use, climate change, atmospheric deposition, and management. Additionally, they measure carbon, water, and energy exchange between ecosystems and the atmosphere using eddy-covariance and biometeorology sensors.  Finally, they forecast the future of ecosystems by combining observations and ecosystem models using Bayesian statistical techniques. Thomas leads an NSF-funded effort to galvanize the field of ecological forecasting using data from the National Ecological Observatory Network, an effort that includes Leah Johnson on the leadership team.

Johnson, Childs, Escobar, and Thomas will focus on mathematic and computational modeling across multiple problem spaces related to infectious disease, climate change, invasive species, and other aspects of rapid environmental change.

“I’m excited at this point in my career to expand the group of people I work with across campus while still representing my home department in the College of Natural Resources and Environment. A career is a set of chapters, and this chapter’s move to Steger Hall will enable me to create new collaborations with quantitative and computational scientists from different departments who are interested in solving problems at the environment-human interface,” Thomas said.

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Categories
Blog Disease Faculty Spotlight

VT researchers establish a reverse genetics system to facilitate COVID-19 research

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From VT News  |  June 4, 2020

The novel coronavirus, or SARS-CoV-2, is currently causing a worldwide pandemic that has infected more than 5 million human beings, and the number continues to climb. Vaccines and antivirals are urgently needed to combat this threat, and the viral genetics that resulted in this outbreak must be identified.

With funding from the Fralin Life Sciences Institute at Virginia Tech, researchers James Weger-Lucarelli and Nisha Duggal, from the Virginia-Maryland College of Veterinary Medicine, are establishing a reverse genetics system for SARS-CoV-2 that will serve as the basis for vaccine design and for studying viral mutations associated with COVID-19 severity and viral transmission.

“The reverse genetics system is the basis for all future studies, including vaccine studies. It will allow us to manipulate the SARS-CoV-2 viral genome so that we can discover weaknesses in the virus to exploit,” said Weger-Lucarelli, a research assistant professor in the Department of Biomedical Sciences and Pathobiology in the Virginia-Maryland College of Veterinary Medicine.

Having studied Zika and mosquito-borne viruses in the past using reverse genetics systems, Weger-Lucarelli and Duggal, who are both affiliated faculty of the Fralin Life Sciences Institute, will create a new reverse genetics system for SARS-CoV-2 that will provide a blueprint for making vaccines and reporter viruses.

SARS-CoV-2 stores its genetic material in ribonucleic acid (RNA), as opposed to deoxyribonucleic acid (DNA), making it difficult for scientists to study and manipulate the viral genome. With a reverse genetics system, scientists can convert the virus’s RNA back into DNA through a process called reverse transcription.

James Weger Lucarelli (left) and Nisha Duggal (right) conducting research in the lab. Lucarelli is wearing a rainbow colored mask while using a laptop. Duggal watches on with a yellow face mask. Ray Meese for Virginia Tech.
James Weger Lucarelli (left) and Nisha Duggal (right) conducting research in the lab. Ray Meese for Virginia Tech.

 

“With Zika virus, we were able to use a lot of the existing animal models that we already had, and we could use the templates from previous reverse genetics systems. This time, we are working with a novel respiratory pathogen; thus, there is a lack of available animal models, and we’re building a new reverse genetics system,” said Duggal, an assistant professor of molecular and cellular biology in the Department of Biomedical Sciences and Pathobiology.

Recent studies have shown that SARS-CoV-2 does not infect wild-type mice; the researchers will eventually study transgenic mice that are susceptible to the virus, but they are not readily available at this time. In the meantime, Weger-Lucarelli and Duggal will modify the virus to a mouse-adapted strain so that they can conduct research effectively. This model will recapitulate human disease for in vivo studies of vaccine efficacy and antiviral therapeutics.

However, Weger-Lucarelli and Duggal’s research won’t stop there. With the novelty of SARS-CoV-2, there are many factors that can contribute to the severity of COVID-19 disease that have yet to be explored in depth, such as obesity and the possibility of fetal transmission.

The Weger-Lucarelli lab is tasked with producing molecular tools to study SARS-CoV-2 and for testing antivirals. The lab is also working with Irving Coy Allen, an associate professor of inflammatory disease in the Department of Biomedical Sciences and Pathobiology, as they investigate the role of obesity and diabetes in COVID-19 severity.

According to estimates, around 43 percent of the United States population is obese, around 10 percent are diabetic, and 35 percent are pre-diabetic. Individuals with these conditions might be more prone to contracting severe diseases, such as COVID-19, because they have an irregular immune response.

“Obesity and diabetes limit a proper immune response to the virus,” said Weger-Lucarelli. “We are trying to figure out how and why the immune system is limited by these conditions so that we can produce therapeutics to prevent the severe disease that these individuals experience.”

Weger-Lucarelli’s $300,000 NSF proposal to study obesity, coronavirus disease, and transmission was just recommended for funding.

In addition to developing the mouse-adapted strain of SARS-CoV-2, the Duggal lab will study how COVID-19 infections differ in males and females and whether newborns of COVID-19 positive mothers may have an acquired immunity to infection through antibodies that are passed to the fetus in utero.

“With our Zika research, we have been looking at the transmission of the virus to fetuses. Based on the few reports that have been published so far for SARS-Cov-2, it looks like transmission of the virus to the fetus is unlikely to be happening. We want to find out how exposure can possibly protect the neonates from subsequent infections,” said Duggal.

Ultimately, Weger-Lucarelli and Duggal hope to share their genetic tools with researchers at Virginia Tech and at other universities around the country. They plan to submit a joint proposal on their reverse genetics system to the National Institutes of Health.

“I think we were lucky to get this COVID-19 seed funding. We are going to use it to help generate tools that everyone can use, which will be really helpful for anyone who wants to study any aspect of the virus or disease,” said Duggal.

In immediate response to the COVID-19 pandemic, Virginia Tech faculty, staff, and students have initiated numerous research projects with local and global salience. Learn more from the Office of the Vice President for Research and Innovation.

– Written by Kendall Daniels and Kristin Rose Jutras

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Categories
Air Blog Disease Faculty Spotlight

Researcher Linsey Marr evaluates efficacy of sterilized N95 respirators, alternative mask materials in filtering particles

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From VT News  |  May 19, 2020

Since March, Virginia Tech civil and environmental engineering professor Linsey Marr, an expert in the airborne transmission of infectious disease, has been testing the efficacy of sterilized N95 respirators and alternative mask materials in filtering out particles.

The rapid science experiments conducted by Marr’s team aim to help quantify how well these forms of personal protective equipment shield their wearers against COVID-19, especially in the face of shortages.

Dealing with sluggish PPE supply chains, the medical community and the wider public have turned to improvisation. Some hospitals have worked to extend the use of their stores of N95 respirators by sterilizing them. Members of the public, advised by the Centers of Disease Control and Prevention to wear masks in places like grocery stores and pharmacies, are also exploring creative problem-solving by sourcing off-the-shelf materials for homemade masks. As these groups adapt, Marr’s team is working to supply them with insights grounded in science.

When testing sterilized N95 respirators, Marr and graduate students Jin Pan and Charbel Harb, members of Applied Interdisciplinary Research in Air (AIR2) Laboratory and fellow civil and environmental engineering professor Hosein Foroutan’s Applied Interdisciplinary Research on Flow Systems (AIRFlowS) Laboratory, found that the respirators retained their ability to filter particles after up to 10 cycles of sterilization by hydrogen peroxide vapor and by ethylene oxide.

“Since I understand how the coronavirus moves around in air, I knew how important it was for health care workers to have proper respiratory protection,” said Marr, the Charles P. Lunsford Professor of Civil and Environmental Engineering. “I knew my lab could help by testing N95s after sterilization to ensure that they could be reused safely. I quickly wrote up a procedure, and my students reconfigured our equipment to start running experiments.”

Marr’s research looks more broadly at the sources, transformations, and fate of air pollutants. Over the years, she’s focused on engineered nano-materials and viral aerosols — mainly those of the flu for the latter — and how they can be physically and chemically transformed in the environment. As she’s pivoted in recent months to apply her insights to the novel coronavirus, Marr, a GCC affiliate, has weighed in on subjects that have captured national media attention, such as the possibility of transmission by inhalation, the 6-foot distance recommendation for running outside, and how virus particles may or may not land on a person’s clothes or other surfaces.

In their look at homemade mask materials, Marr’s team has tested items that have emerged in the public eye in recent months. So far, they’ve tested materials that include Shop-Vac bags, HVAC filters, T-shirts, microfiber cloth, felt, auto shop rags and towels, and coffee filters.

A few top performers and busts emerged from their tests. Microfiber cloth, a material used to clean eyeglasses, filtered out at least 80 percent of particles under optimal conditions, while a heavyweight cotton t-shirt, a shop towel, and a shop rag filtered out only about 10 percent of the hardest particles to remove, and about 50 percent of the larger ones. HVAC filters removed a low of 20 percent of particles; Shop-Vac bags removed at least 60 percent.

The experiments are ongoing, but Marr has been releasing the results in real time on Twitter. She also shared the procedure behind the tests on Twitter, and other aerosol science labs around the country have since adopted these methods to help test materials in their regions.

Linsey Marr
Photo by Ryan Young for Virginia Tech

Reuse as a last resort: Testing sterilized N95 respirators 

The team’s experiments on sterilized N95 respirators were fueled largely by requests from local medical professionals, like Anthony Baffoe-Bonnie, Carilion Clinic’s medical director of infection control and an epidemiologist for the hospital, and infection preventionist Maimuna Jatta.

Baffoe-Bonnie’s team wanted to know if the hospital’s N95 respirators retained their filtration efficacy after up to 10 cycles of sterilization using hydrogen peroxide vapor, a common technique among hospitals. There was added uncertainty in that the Carilion team’s machines use a stronger concentration of hydrogen peroxide than the methodology referenced in the publications they read for guidance.

Marr’s tests showed that the N95 respirators retained their efficacy post-sterilization with the technique, helping the team solidify their procedure. “With that, we knew we could use what we had,” said Baffoe-Bonnie. He said he was grateful to have Marr and her testing resources close by. “I think she’s a godsend in that regard,” Baffoe-Bonnie said. “We had a student drive the stuff over to her, and we had our results back — it couldn’t have been faster.”

Marr’s lab is set up to evaluate filtration efficacy of porous media for particles ranging in size from 0.04 to 1.0 microns. Within that capacity, the team can assess how well a form of PPE meets the standard for N95 respirators, which are required to block at least 95 percent of particles 0.3 microns in diameter.

To test materials, the team sprays sodium chloride particles from a liquid salt solution into a large bag and measures the number and sizes of the particles in the bag. They then use a vacuum pump to pull air containing the particles through the respirator, mask, or material they’re testing, and measure the number and sizes of particles that made it through to the other side.

“The mask or filter removes particles, and we measure hopefully much less than what’s in the big bag,” explained Marr.

In a sea of homemade mask materials, learning which options sink or float

Some of the alternative mask materials arrived in Marr’s lab for testing via Matt Hull, a research scientist at the Institute for Critical Technology and Applied Scienceand Marr’s colleague on the institute’s NanoEarth team. Hull, who earned his master’s and doctoral degrees from Virginia Tech, has worked extensively with Marr and other researchers to understand how nanoscale materials move through the environment and what happens when we’re exposed to them.

Hull recognized that amid the COVID-19 pandemic, there would be a strain on supply chains for protective materials with specialized properties, including materials that the medical community might eye for last-resort use in PPE. He searched for products that might reproduce some of the functionality of certified PPE materials, but could be bought off the shelf.

Hull dropped off potential candidates at the Kelly Hall headquarters of the Institute for Critical Technology and Applied Science, where a conference room that, under normal circumstances, would be booked for committee meetings and thesis defenses was transformed into a staging area for piles of material destined for testing in Marr’s lab down the hall. Hull and the other researchers would exchange text messages when materials were ready for pickup, cobbling together a socially distanced courier service.

“As a scientist, you work your whole life and you go home a lot of nights, and you think, ‘What did I do today?’” said Hull. “‘I maybe edited a paper, sent a few emails.’ You rarely get the chance to contribute so directly to solving a problem.”

Marr’s team has also begun testing several leading, open-source 3D-printed mask designs submitted by Chris Williams, a mechanical engineering professor who has helped coordinate a campus-wide effort to test, design, and produce PPE, ventilator components, and other COVID-19 medical supplies. His lab will base their next steps in PPE production on Marr’s tests.

Her team will continue to run experiments as new ideas for mask materials surface. “We’ll keep testing materials as long as what we’re doing hasn’t been done by other people,” Marr said.

In immediate response to the COVID-19 pandemic, Virginia Tech faculty, staff, and students have initiated numerous research projects with local and global salience. Learn more from the Office of the Vice President for Research and Innovation.

– Written by Suzanne Irby and Eleanor Nelsen

 

CONTACT:
Suzanne Irby

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Categories
Disease Evolution Research

Viruses don’t have a metabolism, but some have the building blocks for one

[vc_row][vc_column][vc_column_text]From VT News | April 6, 2020

In satellite photos of the Earth, clouds of bright green bloom across the surface of lakes and oceans as algae populations explode in nutrient-rich water. From the air, the algae appear to be the primary players in the ecological drama unfolding below.

But those single-celled organisms we credit for influencing the aquatic environment at the base of the food chain may be under the influence of something else: viruses whose genes can reconfigure their hosts’ metabolism.

In a new study published in Nature Communications, a research team from Virginia Tech reported that they had found a substantial collection of genes for metabolic cycles — a defining characteristic of cellular life — in a wide range of “giant viruses.”

Giant viruses disrupt the familiar narrative about viruses — that they’re the tiniest denizens of the microbiome, little more than a stripped-down husk of an organism, just a few genes’ worth of DNA or RNA folded into a shell so small you need an electron microscope to see it. In fact, the giant viruses, 10 times the size of their more compact cousins and with hundreds or even thousands of genes, are so unlike the rest of the family that when the first species was discovered in 1992, researchers dismissed it as bacteria.

They were eventually correctly classified, but even then considered an isolated curiosity. Frank Aylward, an assistant professor of biological sciences in the College of Science who led the research, explained that routine surveys of viral diversity often missed them for a prosaic reason: They’re so big that they get caught in the filters researchers use to separate viruses from bacteria and other larger organisms.

But gradually, it became clear that these oversized viruses were everywhere and were especially plentiful in aquatic environments, where they infect single-celled organisms like algae and protozoans. That’s important, because the metabolism of those comparatively complex organisms — what nutrients they consume, what waste they produce — heavily influences the health of the oceans and lakes they live in and, ultimately, the planet’s carbon cycle.

“They’re all over the biosphere. It’s just we haven’t really paid attention to them,” Aylward said.

Aylward started paying attention after postdoctoral researcher Monir Moniruzzaman, the lead author of the new study,  joined the lab in 2018.

“Monir is the giant virus expert,” Aylward laughed. “He just wouldn’t stop talking about giant viruses, so finally I said, okay, we’ll start working on them.”

Working from publicly available metagenome databases, which house jumbles of genetic data from the vast array of organisms in a variety of environments, Moniruzzaman began to tease out genomes that belonged to giant viruses. Using known giant-virus genes as markers and patterns in the data as clues, he pieced together genomes for 501 giant viruses, mostly from marine and freshwater environments. Those genomes contained the standard features you’d expect — genes that direct the construction of the virus’ protective shell, and that allow it to infect and kill its host.

They didn’t expect to see so many metabolic genes. Metabolism, the collection of processes cells use to extract energy from nutrients, is a hallmark of cellular life, absent from viruses almost by definition. Nevertheless, these giant viruses seemed to have genes linked to several key metabolic pathways in living cells.

These weren’t the first metabolic genes that had turned up in viral genomes, but they included many functions that had never been seen in viruses. Other examples had been isolated viral genes that were virtually identical to their cellular counterparts, suggesting they had been acquired from the host by chance during an infection and pasted into the virus’ genome relatively recently: vestigial artifacts of invasions past rather than functional tools.

The genes Moniruzzaman and Aylward found, on the other hand, comprised large portions of familiar metabolic pathways but had their own unique signature.

“It implies that the viruses have had these genes for millions of years, even billions of years, and they’re virus-specific metabolic genes,” Aylward explained.

That suggests that these genes aren’t just genetic flotsam, but working components the virus deploys as it commandeers its host. In this case, the researchers say, the implication is that the virus is altering the cell’s metabolism.

“Once viruses infect a cell, we can’t think of the cell as being its own autonomous entity anymore,” Aylward says. “The fundamental aspects of cellular physiology are being rewired by these viruses upon infection.”

Changes in the host’s metabolism can shift the balance of nutrients being consumed and released into the environment, giving viruses sway over aquatic biogeochemistry. Even though viruses aren’t alive, Aylward explained, “they are significantly altering the course of life every day in the environment.”

The next step is figuring out how by using experimental studies that can help uncover how these genes function and interact with the host’s native metabolism. The team will also probe the evolution of these genes to determine how they slipped into the viral genome, and when.

Discovering these genes, which stretch our ideas about how giant viruses influence their environment, has broader implications for virology. Finding the building blocks for metabolism in something that’s not alive blurs the distinction between what’s alive and what isn’t.

“I think of these Venn diagrams, where it used to be that there was very little overlap, and the more we learn, the more they continue to overlap,” Aylward said. “Now it’s gotten to the point where there are actually very few genes that are only found in cells, and very few genes that are only found in viruses. In terms of the genomic repertoires, they have much more in common than we would actually expect.”

Moniruzzaman suspects that there are more surprises lurking in these genomes, which are stuffed with what he describes as “viral dark matter” — genes that keep surfacing in studies of giant viruses but whose functions are still unknown.

“Don’t you think they’re fascinating? I just think they’re fascinating,” Moniruzzaman marvels. “They’re just a bag of mystery. They’re like a big forest and you are standing in front of the forest and you don’t know what’s in it. And I think this is the right time to understand it. I think they’re mysterious, that’s what I think.”

This research was supported in part by a Junior Faculty Award from the Institute for Critical Technology and Applied Science. Aylward is an affiliated faculty member of the Global Change Center, housed under the Fralin Life Sciences Institute.

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Biodiversity Conservation Disease Faculty Spotlight Global Change Research

Pathogen levels in the environment drive disease outbreaks in bats

[vc_row][vc_column][vc_column_text]From VT News | March 16, 2020

Since 2005, millions of bats have perished from white-nose syndrome, a disease caused by the fungus Pseudogymnoascus destructans. Although the disease has been found throughout much of the world, severe population declines have only occurred in North America — and now researchers at Virginia Tech know why.

In a new study led by Joseph Hoyt, an assistant professor in the Department of Biological Sciences in the College of Science, researchers have found that the pathogen levels in the environment play a major role in whether bat populations are stable or experience severe declines from white-nose syndrome.

Hoyt and his international team of researchers published their findings in the Proceedings of the National Academy of Sciences on March 16.

“This study shows that more contaminated environments, or potential ‘hot spots,’ are going to result in higher disease impacts. By understanding the relationship between how much pathogen is present in the environment and the size of an outbreak, we can know exactly how much environmental sanitization is needed to reduce the epidemic potential,” said Hoyt.

When infectious diseases first arise, it is crucial to understand how the disease is being transmitted. With a pathogen like Pseudogymnoascus destructans, which can exist outside of the host, researchers looked to the environmental pathogen reservoir — or the habitat in which a pathogen persists or grows in the absence of hosts.

Pseudogymnoascus destructans is a cold-loving fungus, which resides on the walls of caves, mines, and other subterranean environments. Every year, as the cold and debilitating winter draws near, bats hibernate in these infected sites until they can return to the landscape in spring. And it is during this time that bats contract white-nose syndrome.

As Hoyt and his team journeyed out to find the historical origin of this disease, they were the first to find that the pathogen has already been present in Asia for thousands of years. In an even more astounding discovery, they found that European and Asian bat populations face little to no impacts from white-nose syndrome compared to bats in North America.

A cluster of greater horseshoe bats (Rhinolophus ferrumequinum) roosting in a cave at the end of winter in Jilin province, China. They are tightly packed, and one bat is flying away from the cluster and towards the camera.
A cluster of greater horseshoe bats (Rhinolophus ferrumequinum) roosting in a cave at the end of winter in Jilin province, China. Photograph courtesy of Joseph R Hoyt.

This unprecedented study revealed that the environmental pathogen reservoir in European and Asian sites decayed over the summer months, which left a smaller amount of pathogen in the environment for bats to come into contact with the following winter. In contrast, there was no decay of the pathogen in sites over the summer in North America, which resulted in widespread infection and mortality.

“The fact is that bats are experiencing much less severe infections at the beginning of the hibernation season across Europe and Asia. As a result, they are still getting infected but the process of infection is delayed relative to North American bats. So, they are experiencing far lower transmission from the environment than bats experience here in North America,” said Kate Langwig, the second author of this paper and an assistant professor in the Department of Biological Sciences in the College of Science and an affiliated faculty member of the Global Change Center, housed under the Fralin Life Sciences Institute. “The differences in the environmental reservoir are really important for driving the dynamics of the disease across space.”

With lower transmission of the pathogen and some time on their side, bats will be able to emerge from their infected roosts in just enough time to escape certain death.

“Because the pathogen decays in the environment over summer in Europe and Asia, most bats don’t become infected until mid- to late- winter, which is too late for the infections to manifest into mortality. If you have delayed transmission, then bats are able to emerge in the spring and clear infection before it can ever result in death,” said Hoyt.

This is one of the first papers to link the extent of the environmental reservoir to the size of an outbreak, the number of individuals that become infected, the severity of those infections, and population impacts.

Hoyt hopes that this paper will highlight the importance of environmental pathogen reservoirs in driving infectious disease outbreaks.

“The environmental pathogen reservoir has the potential to be really important. The idea that as you get a more contaminated environment, that scales with the degree of population impacts, is something that hasn’t really been demonstrated before,” said Hoyt.

Hoyt and his team are now trying to use findings from Eurasian bat populations to help North American bats. More specifically, they are trying to reduce the amount of pathogen in the environment in North America over summer when bats are absent from these sites.

“We are trying to replicate the pathogen decay that is happening in Europe and Asia, and delay transmission. If we can push bats to not get infected until later in the winter, then they might be able to survive until spring,” said Hoyt.

This project received a majority of funding from the National Science Foundation and the U.S. Fish and Wildlife Service. Additional funding was provided by the National Natural Science Foundation of China, Program for Introducing Talents to Universities, Jilin Provincial Natural Science Foundation, Mongolian State University of Education, and the Japan Society for the Promotion of Science KAKENHI.

– Written by Kendall Daniels

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Blog Disease Food & Agriculture Global Change Research

Wuhan coronavirus has linkages with wild animals, says GCC affiliate Luis Escobar

[vc_row][vc_column][vc_column_text]From VT News | January 31, 2020

The consumption of wildlife in China may be the main driver of the country’s coronavirus outbreak, says a Virginia Tech expert.

“It’s not surprising that the coronavirus first identified in Wuhan has linkages with animals, especially wildlife,” said wildlife epidemiology expert Luis Escobar. “China has important traditions related to the consumption of wildlife products, which elevates the risks for emerging diseases. While other countries and cities have high population densities and massive amounts of tourists, we do not see epidemics like the SARS or Wuhan coronaviruses that emerged in China.”

Escobar explains that 75 percent of emerging infectious organisms known to be pathogenic to humans have their origin in animals.

Escobar says “a recent study predicts that severe traveler restrictions from and to Wuhan would likely have minor impact on reducing the spread of the epidemic to other regions. Surveillance is very important now for those with and without symptoms to better understand groups at risk.”

As global health authorities work to prevent further spread of the coronavirus, Escobar says this is a great example of how authorities and researchers should respond to epidemics.

“Compared to previous epidemics of emerging illnesses, Chinese authorities and researchers working on the Wuhan coronavirus epidemic have been open. Data associated with the epidemic have been shared broadly and openly, which has allowed for immediate assessments of the plausible origins and potential transmission risks by research teams around the world.”

“For the first time, China shows signs of being serious about banning wildlife trade to reduce emerging disease outbreaks, which is a good indication that authorities are using scientific evidence to prevent new epidemics in the future,” says Escobar.

About Escobar

Luis Escobar is an assistant professor of disease ecology in the Department of Fish and Wildlife Conservation in Virginia Tech’s College of Natural Resources and Environment. His research focuses on the distribution of wildlife diseases and emerging pathogens at global scales. He uses ecological, biogeographic, and modeling approaches for the understanding of diseases spread under diverse land use and climate change conditions. He is particularly interested in global health and One Health. More here.

Interview

To secure an interview with Escobar, contact Shannon Andrea in the media relations office at sandrea@vt.edu or 703-399-9494.

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Blog Climate Change Conservation Disease Drinking water Evolution Faculty Spotlight Food & Agriculture Global Change Research

The GCC welcomes seven new faculty affiliates

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Meet our newest faculty affiliates:

 

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Dr. Cully Hession

Professor, Department of Biological Systems Engineering

Research focus: His lab focuses stream channel structure and sediment dynamics, influence of human activities on streams, techniques for measuring and improving in-stream habitat, and development of technologies and strategies for successful stream restoration.  Current research focuses on using drones and drone-based lidar to map riverscapes and tracer studies to better understand sediment transport and fate. Dr. Hession is also PI/co-Director of an interdisciplinary research and extension training program called “Training Future Leaders to Solve Resource Challenges at the Confluence of Water and Society.”[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_separator style=”shadow”][/vc_column][/vc_row][vc_row][vc_column width=”1/2″][vc_single_image image=”47579″ img_size=”275×355″ style=”vc_box_border”][/vc_column][vc_column width=”1/2″][vc_column_text]

Dr. Florian Zach

Assistant Professor, Deparment of Hospitality & Tourism Management

Research interests:  Dr. Zach is interested in strategic issues that support the sustainable development of tourism destinations. He has investigated the inter-organizational collaboration and networks to understand how destination stakeholders collectively develop tourism innovations. Additionally, he works with colleagues to understand human-computer interaction issues stemming from the use of cutting-edge technologies in the context of tourism. Current projects include exploring the effects of summer adventure parks built by ski resorts in the Austrian Alps as a response to shorter winter and longer summer seasons and also the impacts of the 2018 Florida Red Tide on hotel & short-term rentals (Airbnb & similar).[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_separator style=”shadow”][/vc_column][/vc_row][vc_row][vc_column width=”1/2″][vc_single_image image=”47688″ img_size=”275×355″ style=”vc_box_border”][/vc_column][vc_column width=”1/2″][vc_column_text]

Dr. J. Leighton Reid

Assistant Professor, School of Plant & Environmental Sciences

Research interests: Dr. Reid’s research interests encompass tropical forest restoration in Latin America and Madagascar as well as temperate forest, woodland, and grassland restoration in the eastern United States. Specifically, he investigates how local restoration interventions interact with their surrounding landscape to affect biodiversity recovery, how keystone plant species can be used to catalyze ecological succession, why some restored ecosystems persist much longer than others, and what soil and environmental factors limit the recolonization of rare plants in regenerating ecosystems.[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_separator style=”shadow”][/vc_column][/vc_row][vc_row][vc_column width=”1/2″][vc_single_image image=”47595″ img_size=”275×355″ style=”vc_box_border”][/vc_column][vc_column width=”1/2″][vc_column_text]

Dr. Rachel Reid

Research Scientist, Department of Geosciences

Research interests: Dr. Reid is a paleoecologist interested in how disturbances, such as climate and environmental change, impact species, ecosystems, and their interactions over a range of timescales. As a Research Scientist at Virginia Tech, Dr. Reid runs the Stable Isotope Laboratory.[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_separator style=”shadow”][/vc_column][/vc_row][vc_row][vc_column width=”1/2″][vc_single_image image=”47396″ img_size=”275×355″ style=”vc_box_border”][/vc_column][vc_column width=”1/2″][vc_column_text]

Dr. Theo Lim

Assistant Professor, Department of Urban Affairs & Environmental Planning

Research interests: Dr. Lim’s research focuses on the environmental planning of linked land, water, infrastructure, and social systems. His interests include urban hydrology, distributed stormwater practices, community green infrastructure, energy planning in agricultural and rural settings, land development impacts on the hydrological cycle, and applications of data science in urban & environmental planning.[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_separator style=”shadow”][/vc_column][/vc_row][vc_row][vc_column width=”1/2″][vc_single_image image=”47637″ img_size=”275×355″ style=”vc_box_border”][/vc_column][vc_column width=”1/2″][vc_column_text]

Dr. Ben Gill

Associate Professor, Department of Geosciences

Research interests: Dr. Gill specializes in reconstructing the present and past chemical cycles on our planet. He leads the Biogeochemistry Laboratory Group at Virginia Tech. The main research focus of his group concerns understanding the connections between major changes in the environment (oxygenation/deoxygenation oceans, climatic warming and cooling, etc.) and major events in the history of life (originations, diversifications and mass extinctions).[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_separator style=”shadow”][/vc_column][/vc_row][vc_row][vc_column width=”1/2″][vc_single_image image=”47465″ img_size=”275×355″ style=”vc_box_border”][/vc_column][vc_column width=”1/2″][vc_column_text]

Dr. James Weger-Lucarelli

Research Assistant Professor, Department of Biomedical Sciences & Pathology

Research interests: Dr. Weger-Lucarelli’s research focuses on understanding viral and host determinants that mediate disease severity, transmission, evolution, and protection against mosquito-borne viruses. The Weger-Lucarelli lab uses molecular, virological, and computational methods to study these interactions, with the goal to recognize and study emerging viral threats before they product massive outbreaks.  He is also working to produce innovative vaccines to prevent mosquito-borne viral disease.[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][vc_separator style=”shadow” border_width=”5″][/vc_column][/vc_row]

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Blog Disease Faculty Spotlight Food & Agriculture Global Change Research

Researchers combine technologies to resolve plant pathogen genomes

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From VT News | January 27, 2020

With the help of new genomic sequencing and assembly tools, plant scientists can learn more about the function and evolution of highly destructive plant pathogens that refuse to be tamed by fungicides, antibacterial, and antivirals.

But using these genomic technologies is not an easy task. The process not only requires time, but also money. In a recent paper published in Molecular Plant-Microbe Interactions, David Haak and John McDowell, from the School of Plant and Environmental Sciences in the College of Agriculture and Life Sciences, proved that these costly processes can be improved by combining two generations of technology.

What used to take a year-and-a-half and $2 million to complete can now be done within nine days for $1,000 – and the technology performs with greater accuracy and field applicability than ever before.

“Think of it as analogous to a library full of books that are two-thirds or three-quarters completely written. What David has developed is a technology through which he could go to the library and finish those books really quickly and really accurately for a really low price point,” said McDowell, the J. B. Stroobants Professor of Biotechnology.

Before this project began, Haak, an assistant professor and affiliate with the Global Change Center, and his team had been trying to prove that it was possible to generate a completed assembly in a relatively short period of time – but they needed a relatively complex genome to test their theory. A few hallway conversations later, Haak and his students joined forces with McDowell and his team to unravel the complex genome of Phytophthora capsici.

“P. capsici is a representative of a really destructive group of pathogens. Its evolutionary cousin is the pathogen that caused the Irish Potato Famine in the 19th century, which killed at least a million people and caused at least a million more to relocate. These pathogens are still causing difficulty today,” said McDowell. “One of the reasons for that is because their genomes are exquisitely configured to enable them to evolve ways around interventions that farmers put in place in the field.”

A microscopic image of a large root, which divides the photo into two diagonal sections. On each side of the root, there are many P. capsici spores, which resemble lollipops.
An image of P. capsici spores that are attached to an Arabidopsis root and initiating the process of penetration. John Herlihy for Virginia Tech.

 

In this species of pathogen, virulence genes are often located in gene-poor regions interspersed with repetitive regions within the genome. These repetitive regions are prone to rapid evolution and are the key to understanding its pathogenicity, or its ability to cause disease.

To better understand the inner workings of P. capsici, scientists must extract a DNA sample from the pathogen and perform genetic sequencing. Genetic sequencing is a process that determines the order of the nitrogenous bases – or the As, Cs, Gs, and Ts – that make up an organism’s DNA.

However, genomic sequencing can read only a certain amount of DNA segments at one time. Scientists must then take these small sequences and re-assemble them so that the DNA is presented in the right order.

“Generating the sequence data, isn’t really the problem. It’s assembling that data. It’s putting together the sequence information in the right order. The repeat-rich regions make us sometimes put two genes together that don’t belong together or separate a full gene into two halves because we think a repeat goes right in the middle,” said Haak.

All in all, resolving the genome of an organism requires powerful technology – and patience. And although bioinformatic technology has made great leaps and bounds over the years, each generation isn’t necessarily better than the last. Each generation of technology has its own forte.

Using first-generation technology, it would take one-and-a-half years and around $2 million to sequence the P. capsici genome. But with Haak’s technology, it will take just nine days from DNA extraction to a polished assembly – and only cost $1,000. To make things even better, this technology will be able to sequence 100,000 times more information in roughly 1.5 percent of the time. And the technology is the size of a thumb drive.

Second-generation technology performs short read assemblies, which are extremely accurate; however, they do not span across repetitive regions well. And when scientists must go back and reassemble the genome, there is a reasonable chance of error.

“What happens with the short reads is that we don’t know where those repeats begin and end, so we don’t know where to put them to arrange them appropriately,” said Haak.

Oxford Nanopore Technologies (ONT) MinION, or long-read sequencing, is the third generation of sequencing technology, but it has the opposite problem: it is far less accurate but it can give them a better overall picture by spanning across these critical repetitive regions.

Haak and his team combined these second- and third-generation technologies to exploit the accuracy of the former with the ability to span the repeated regions of the latter. It’s the best of both worlds.

Upon using this new technology on P. capsici, Haak and McDowell got quite a shock. Haak and his group revealed that the genome is 1.5 times bigger than previously thought.

“That’s 30 percent of the genome that we didn’t even know existed, and that particular fraction of the genome is, undoubtedly, enriched with the sorts of genes that really make a difference in helping us understand what interacts with the plant or responds to fungicides or farmers’ spray,” said McDowell.

For Haak, the most exciting thing about the results of this paper is its proof-of-concept.

“We have something called the sequence archive database, which is full of all sorts of short-read sequences. We can actually leverage all of that existing data with this newer technology to be able to produce more genomes of this quality,” said Haak.

Haak’s new generation of technology is expected to revolutionize the way in which scientists collect genomic data. With their newly acquired, affordable, real-time data, scientists will be able to improve previous assemblies and quickly generate new ones that they can share to the sequence archives database. On a grander scale, this technology will advance the field of plant genomics and the worldwide effort to save the crop industry from destructive pathogens.

Now that Haak and McDowell have an estimated 97 percent of the genome for P. capsici in their grasps, they plan to use this information as supporting data for two new grant proposals. One proposal will focus on tomato and soybean diseases caused by pathogens of the Phytophthora group and the other proposal will focus on lavender, yet another victim of Phytophthora.

For Haak, this project was special because it was supported by a grant from the Fralin Life Sciences Institute at Virginia Tech with funds allocated to support the Global Systems Science Destination Area.

McDowell added, “I think it speaks to the environment here at Virginia Tech, promoted by Fralin, that enables these sorts of collaborations to come together and get some critical support in the early phase.”

– Written by Kendall Daniels

 

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Blog Disease Environmental Justice Global Change Hollins Partnership Research Undergraduate Experiential Learning

GCC Partners with Hollins University to promote undergraduate research opportunities

[vc_row][vc_column][vc_column_text]From VT News | December 2, 2019

A partnership between Virginia Tech’s Global Change Center and Hollins University will continue to blossom into its third year, pairing distinguished undergraduate students with Virginia Tech professors for a summer of unique research opportunities.

Hollins University is a private, women’s liberal arts college in Roanoke, Virginia, and students who are contemplating graduate studies and environmental research careers are currently applying for the summer 2020 installment of the program on the Blacksburg campus.

Over the summer of 2019, the Global Change Center hosted Udipta Bohara, a junior majoring in biology with minors in mathematics and chemistry, and Grishma Bhattarai, a senior double-majoring in economics and mathematics. Both aspire to complete advanced degrees after graduating from Hollins. By working at Virginia Tech with professors Dana Hawley, Kendra Sewall, and Kelly Cobourn, they gained understanding about what it’s like to work closely with research faculty on complex projects.

In Hawley’s biology lab, Bohara worked on a project seeking to understand the differences in how long the bacterial pathogen Mycoplasma gallisepticum stays active in different environments. This bacterium can cause severe eye infections in songbirds, and researchers are currently trying to discern just how virulent the disease is and how long it can remain active on a birdfeeder, where it is most commonly spread. Bohara’s work involved taking blood samples from birds and swabbing bird feeders, as well as setting up and running DNA and RNA-based assays.

Udipta pipetting samples collected by swabbing a bird feeder in order to quantify how much bacterial pathogen was present on the feeder port.
Bohara pipetting samples collected by swabbing a bird feeder in order to quantify how much bacterial pathogen was present on the feeder port. Courtesy of Virginia Tech.

When first experiments didn’t go as expected, she also learned valuable skills that all successful scientists practice: how to develop alternative questions, adjust protocols, and change the scope of experiments when things don’t go exactly as planned. Kendra Sewall, an associate professor in the School of Neuroscience, noted that this kind of adjustment “is a way of coming back with another question that might be better … science is an iterative process. You’re never done.”

Bohara felt that the positive mentorship of her professors and lab team and successfully shifting her project for the second half of the summer were some of the most inspirational and exciting parts of her summer at Virginia Tech. She described it as “a life-changing opportunity.”

Chava Weitzman, a postdoc in the Hawley lab who worked closely with Udipta during her project, said, “It’s been really fun to watch Udipta’s confidence in the lab and feeling of ownership in the experiments grow over the summer.” Hawley added, “Udi’s project helped us start a whole new line of techniques in our lab. It was wonderful to have her here as an enthusiastic stimulus for trying something new, and we’ll definitely be using Udi’s assays to try for a new NSF grant in the fall.”

Bhattarai’s experiences with Associate Professor Kelly Cobourn in the Department of Forest Resources and Conservation were equally positive. Bhattarai focused on investigating food insecurity as a function of assistance programs and gender. She wondered, is food assistance more effective for male- or female-headed households? How exactly are people being helped (if at all) and does assistance improve their access to food? Bhattarai’s interest in economics and gender combined perfectly with Cobourn’s own interests in creating models to predict food insecurity in regions like South Sudan and Ethiopia.

Grishma in the Center for Environmental Analytics and Remote Sensing (CEARS) lab analyzing large datasets to explore the interaction between assistance, gender, and food security. Courtesy of Virginia Tech.
Bhattarai in the Center for Environmental Analytics and Remote Sensing lab analyzing large datasets to explore the interaction between assistance, gender, and food security. Courtesy of Virginia Tech.

Cobourn explained that “the difficult challenge as an economist is that you can’t usually design experiments. You have to work with what you’re given.” Mining the massive amounts of data from the World Bank to find the right data set became Bhattarai’s biggest challenge. “If you ask the wrong questions,” she said, “you’ll get the wrong information. You have to be sure your own biases aren’t reflected.”

Bhattarai recently presented her research at an international applied agriculture and economics conference in Atlanta. “It was the experience of a lifetime for me personally, to be surrounded by people in academia driven to solve the world’s problems with their research. It was an amazing opportunity.”

“Bhattarai has been wonderful to work with,” said Cobourn. “She’s very intrinsically motivated, energetic, and self-directed. She had a clear idea of what she wanted to do, and all I had to do was steer her toward the right questions. It’s important to recognize that being able to do all this research in two months is phenomenal.”

Bhattarai and Bohara agree that the opportunity to participate in intensive research at Virginia Tech has helped them better understand what graduate school might look like, laying a solid foundation for these students’ future careers in research. Collaborative work, positive mentorship, and exciting research made for a rewarding summer for both students.

The Global Change Center’s mission is to advance interdisciplinary scholarship and education to address critical global changes impacting the environment and society. For more information about the Hollins-GCC partnership, visit the GCC website.

“It is extremely exciting to see the positive impact that this program is having on young women who plan to pursue graduate training after finishing their studies at Hollins. I continue to be impressed by the talented and motivated students from Hollins and am grateful that they regard Virginia Tech as a place where they can obtain high caliber research training under the mentorship of our outstanding faculty. I am hopeful that this partnership will continue long into the future,” said William Hopkins, director of the Global Change Center and professor in the Department of Fish and Wildlife Conservation in the College of Natural Resources and Environment.

 

Related News: Virginia Tech’s Global Change Center and Hollins University partner to increase student careers in life science research

~Written by Jessica Nicholson and Tiffany Trent 

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