May. 15, 2023
James X Zhong Manis

James X Zhong Manis

James X. Zhong Manis, who is pursuing his Ph.D. in Physical Chemistry at Georgia Tech, will get a chance to conduct his thesis research at a Department of Energy national laboratory at Stanford University, thanks to his selection to the DOE Office of Science Graduate Student Research (SCGSR) program.

The goal of the SCGSR program is to prepare graduate students for science, technology, engineering, or mathematics (STEM) careers critically important to the DOE Office of Science mission. The agency provides graduate thesis research opportunities through extended residency at DOE national laboratories.

“I am so excited and feel extremely lucky to have this opportunity to continue my research with DOE help,” Manis said. “I am thankful for everyone’s help to get me where I am, especially my principal investigator Thomas Orlando, our lab senior research scientist Brant Jones, my collaborating DOE scientist Thorsten Weber, and also everyone else in my research group. I am so thrilled to be working with world class scientists on cutting edge equipment.”

Manis is one of 87 awardees from 58 different universities who will conduct research at 16 DOE national laboratories. The research projects proposed by the new awardees are aligned with the priority mission areas of the DOE Office of Science that have a high need for workforce development. 

“The SCGSR program provides a way for graduate students to enrich their scientific research by engaging with researchers at DOE National Labs, learning from world class scientists, and using state-of-the-art equipment and facilities,” notes Asmeret Asefaw Berhe, Director of the DOE Office of Science. “In addition, they get valuable opportunities to network and observe firsthand what it’s like to have a scientific career. I can’t wait to see what these young researchers do in the future. I know they will meet upcoming scientific challenges in new and innovative ways.”  

Manis, who also earned a Bachelor of Science degree from the Wallace H. Coulter Department of Biomedical Engineering in 2018, will join the DOE’s Gas Phase Chemical Physics program at the Stanford Linear Accelerator Center (SLAC) at Stanford University. The Center supports research on fundamental gas-phase chemical processes important in energy applications.

SCGSR awardees work on research projects of significant importance to the Office of Science mission that address critical energy, environmental, and nuclear challenges at national and international scales. Projects in this new cohort span eight different  DOE Office of Science research programs

Manis’ project falls into the Basic Energy Sciences category. “I am interested in understanding the low energy electron interaction with biomolecules, which is a potential way of causing DNA damage,” he said. “The research I will conduct at the SLAC National Accelerator Laboratory is to first help in commissioning the DREAM (Dynamic REAction Microscope) end station in the TMO (time-resolved atomic, molecular and optical science) instrument hub.

“I have never visited SLAC before, but I am extremely excited to work there,” Manis added. “It’s going to be a change of pace collaborating with another group of scientists, and I can’t wait to start.”

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Apr. 24, 2023
A project rendering for the New York Climate Exchange (The Exchange) on Governors Island in New York City. The center is slated to open in 2028.

A project rendering for the New York Climate Exchange (The Exchange) on Governors Island in New York City. The center is slated to open in 2028.

Georgia Tech will be a key partner for the New York Climate Exchange (The Exchange), a first-of-its-kind international center for developing and deploying dynamic solutions to the global climate crisis. In addition to convening the world’s leaders and climate experts, The Exchange will address the social and practical challenges created by climate change — including commercially viable research and ideas that lead to immediate action on local and global levels.

“Today's climate issues are urgent, and environmental justice and ecological sustainability necessitate action from leaders across the world,” said Chaouki Abdallah, executive vice president for research at Georgia Tech. “As a core partner of The Exchange, Georgia Tech will provide research expertise in the areas of energy, urban planning, bi­­ological ecosystems, public policy, and more, and we look forward to playing an instrumental role in bringing its mission to fruition.”

Georgia Tech researchers are studying glacial melt, coral growth, sea level rise, and other climate concerns in the state of Georgia and around the world and will share their data and research results with partners at The Exchange. Likewise, research at The Exchange will be applicable for towns and cities across Georgia, allowing state leaders to take advantage of economic opportunities that arise when climate change is addressed head on.  

In addition to contributing critical research across the many areas of climate change, Georgia Tech leads major initiatives that are focused on solving the crises laid out in the UN’s Sustainable Development Goals. Generation 2 Reinvented Toilet (G2RT) — a solution to the world’s water and sanitation problem — is led by Shannon Yee, associate professor in the George W. Woodruff School of Mechanical Engineering at Georgia Tech. This cost-effective, globally scalable reinvented toilet with built-in human waste treatment will ensure that drinking water stays clean and will improve public health around the world.

Georgia Tech is also a leading partner of the Ocean Visions – UN Decade Collaborative Center for Ocean-Climate Solutions, an international center headquartered at the Georgia Aquarium that aims to co-design, develop, test, fund, and deliver scalable and equitable ocean-based solutions to reduce the effects of climate change and build climate-resilient marine ecosystems and coastal communities. Championed at Georgia Tech by Susan Lozier, dean and Betsy Middleton and John Clark Sutherland Chair in the College of Sciences, the Center also supports opportunities to accelerate ocean-based carbon dioxide removal research and advance sustainable ocean economies.

“We are looking forward to contributing and demonstrating some of the engineering sustainability solutions that have been developed at Georgia Tech with New York City and the world,” said Yee. “Many of the technical and economic solutions that serve the state of Georgia, the coastal city of Savannah, and the urban center of Atlanta can also serve the urban harbor of New York City. Similarly, the innovations and economic opportunities that address climate change can be shared with and benefit Georgia. This collaboration embodies the concept of an exchange where we share with one another.”

As The Exchange’s anchor institution, Stony Brook University will build and operate the center which will be located on Governors Island in New York City. The center is slated to open in 2028.

“It is becoming clear year after year in New York, and around the world, that the impacts of climate change are real and are here,” said Kevin Reed, associate dean for Research and associate professor in the School of Marine and Atmospheric Sciences at Stony Brook. “By partnering with communities, industries, governments, and universities, The Exchange will help to accelerate the implementation of urban solutions to these climate impacts through an interactive research ecosystem where community engagement is paramount. As a climate scientist, I recognize that New Yorkers need solutions to the climate crisis now, and The Exchange will help to make that a reality.”

 

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Georgia Parmelee | georgia.parmelee@gatech.edu

Apr. 20, 2023
Steven Chu (Credit: Imke Lass/Redux)
Steven Chu (Credit: Larry Downing/Reuters)

On April 26, 2023, the School of Physics and College of Sciences at Georgia Tech will welcome Stanford University physicist Steven Chu to speak on climate change and innovative paths towards a more sustainable future. Chu is the 1997 co-recipient of the Nobel Prize in Physics, and in his former role as U.S. Secretary of Energy, became the first scientist to hold a U.S. Cabinet position.

About the Talk

The event is part of the School of Physics “Inquiring Minds” public lecture series, and will be held at the Ferst Center for the Arts. The talk is free and open to campus and the Atlanta community, and no RSVP is required. Refreshments begin at 4:30, and the lecture will start at 5 p.m. ET.

“The multiple industrial and agricultural revolutions have transformed the world,” Chu recently shared in an abstract for the lecture. “However, an unintended consequence of this progress is that we are changing the climate of our planet. In addition to the climate risks, we will need to provide enough clean energy, water, and food for a more prosperous world that may grow to 11 billion by 2100.” 

The talk will discuss the significant technical challenges and potential solutions that could provide better paths to a more sustainable future. “How we transition from where we are now to where we need to be within 50 years is arguably the most pressing set of issues that science, innovation, and public policy have to address,” Chu added. 

The event’s faculty host is Daniel Goldman, Dunn Family Professor in the School of Physics at Georgia Tech.

About Steven Chu

Steven Chu is the William R. Kenan, Jr. Professor of Physics and a professor of Molecular and Cellular Physiology in the Medical School at Stanford University.

Chu served as the 12th U.S. Secretary of Energy from January 2009 until the end of April 2013. As the first scientist to hold a U.S. Cabinet position and the longest serving Energy Secretary, Chu led several initiatives including ARPA-E (Advanced Research Projects Agency – Energy), the Energy Innovation Hubs, and was personally tasked by President Obama to assist in the Deepwater Horizon oil leak.

In the spring of 2010, Chu was the keynote speaker for the Georgia Tech Ph.D. and Master's Commencement Ceremony.

Prior to his cabinet post, Chu was director of the Lawrence Berkeley National Laboratory, where he was active in pursuit of alternative and renewable energy technologies, and a professor of Physics and Applied Physics at Stanford, where he helped launch Bio-X, a multi-disciplinary institute combining the physical and biological sciences with medicine and engineering. Previously he also served as head of the Quantum Electronics Research Department at AT&T Bell Laboratories.

He is the co-recipient of the 1997 Nobel Prize in Physics for his contributions to laser cooling and atom trapping. He is a member of the National Academy of Sciences, the American Philosophical Society, the American Academy of Arts and Sciences, the Pontifical Academy Sciences, and of seven foreign academies. He formerly served as president, and then chair of the American Association for the Advancement of Science.

Chu earned an A.B. degree in mathematics and a B.S. degree in physics from the University of Rochester, and a Ph.D. in physics from the University of California, Berkeley, as well as 35 honorary degrees.

He has published over 280 papers in atomic and polymer physics, biophysics, biology, bio-imaging, batteries, and other energy technologies. He holds 15 patents, and an additional 15 patent disclosures or filings since 2015.

 

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Jess Hunt-Ralston
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Mar. 31, 2023
An aerial view of the SPRUCE enclosure.

An aerial view of the SPRUCE enclosure.

Small glass jars containing sphagnum moss.

Sphagnum mosses were taken from different SPRUCE enclosures and incubated in glass jars for the study (Photo Jennifer Glass).

A closeup of a member of the research team holding Sphagnum moss

A closeup of a member of the research team holding Sphagnum moss, one of the key drivers of carbon sequestration in peatlands. (Photo Jennifer Glass).

If you’re an avid gardener, you may have considered peat moss — decomposed Sphagnum moss that helps retain moisture in soil — to enhance your home soil mixture. And while the potting medium can help plants thrive, it’s also a key component of peatlands: wetlands characterized by a thick layer of water-saturated, carbon-rich peat beneath living Sphagnum moss, trees, and other plant life. 

These ecosystems cover just 3% of Earth’s land area, but “peatlands store over one-third of all soil carbon on the planet,” explains Joel Kostka, professor and associate chair of Research in the School of Biological Sciences at Georgia Tech.

This carbon storage is supported in large part by microbes. Two microbial processes in particular — nitrogen fixation and methane oxidation — strike a delicate balance, working together to give Sphagnum mosses access to critical nutrients in nutrient-depleted peatlands. 

The coupling of these two processes is often referred to as the “missing link” of nutrient cycling in peatlands. Yet, how these processes will respond to changing climates along northern latitudes is unclear.

“There are tropical peatlands — but the majority of peatlands are in northern environments.” notes Caitlin Petro, a research scientist who works with Kostka in Biological Sciences at Tech. “And those are going to be hit harder by climate change.”

Kostka and Petro recently led a collaborative study to investigate how this critical type of ecosystem (and the “missing link” of microbial processes that support it) may react to the increased temperature and carbon dioxide levels predicted to come with climate change. The team, which also includes researchers from the Oak Ridge National Laboratory (ORNL), Florida State University, and the University of Tennessee, Knoxville, just published their work in the scientific journal Global Change Biology.

By testing the effects of increasing temperature and carbon dioxide on the growth of Sphagnum moss, its associated microbiome, and overall ecosystem health, Kostka and Petro say computational models will be better equipped to predict the effects of climate change.

“Down the road,” Kostka added, “we hope the results can be used by environmental managers and governments to adaptively manage or geoengineer peatlands to thrive in a warmer world.”

Raising the heat

To see how northern peatlands will react to climate change, the team, which also included School of Earth and Atmospheric Sciences Associate Professor Jennifer Glass, turned to the ORNL Spruce and Peatland Responses Under Changing Environments (SPRUCE) experiment — a unique field lab in northern Minnesota where the team warms peat bogs and experimentally changes the amount of carbon dioxide in the atmosphere. 

Starting in 2016, the team exposed different parts of SPRUCE’s experimental peatlands to a gradient of higher temperatures ranging from an increase of 0°C to 9°C, capturing the Intergovernmental Panel on Climate Change models’ predicted 4°C to 6°C increase in northern regions by 2100.

The moss’s reaction was significant. Although nearly 100% of the bog’s surface was covered in moss at the beginning of the experiment, moss coverage dropped with each increase in temperature, plummeting to less than 15% in the warmest conditions.

Critically, the two microbial processes that had previously been consistently linked fell out of sync at higher temperatures. 

“Peatlands are extremely nutrient-poor and microbial nitrogen fixation represents a major nitrogen input to the ecosystem,” Kostka explained. Fixing nitrogen is the process of turning atmospheric nitrogen into an organic compound that the moss can use for photosynthesis, while methane oxidation allows the moss to use methane released from decomposing peat as energy. “Methane oxidation acts to fuel nitrogen fixation while scavenging a really important greenhouse gas before it is released to the atmosphere. This study shows that these two processes, which are catalyzed by the Sphagnum microbiome, become disconnected as the moss dies.”

“These processes occurring together are really important for the community,” Petro explained. Yet many microbes that are able to both fix nitrogen and oxidize methane were absent in the mosses collected from higher temperature enclosures. And while elevated carbon dioxide levels appeared to offset some of the changes in nitrogen cycling caused by warming, the decoupling of these processes remained.

“These treatments are altering a fairly well-defined and consistent plant microbiome that we find in many different environments, and that has this consistent function,” Petro explained. “It's like a complete functional shift in the community.” 

Though it’s not clear which of these changes — the moss dying or the altered microbial activity — is driving the other, it is clear that with warmer temperatures and higher carbon dioxide levels comes a cascade of unpredictable outcomes for peat bogs.

“In addition to the direct effects of climate warming on ecosystem function,” Petro adds, “it will also introduce all of these off-shooting effects that will impact peatlands in ways that we didn't predict before.”

This work was supported by the National Science Foundation (DEB grant no. 1754756). The SPRUCE project is supported by the U.S. Department of Energy's Office of Science, Biological, and Environmental Research (DOE BER) and the USDA Forest Service.

DOI: https://doi.org/10.1111/gcb.16651

Citation: Petro, C., et al. Climate drivers alter nitrogen availability in surface peat and decouple N2 fixation from CH4 oxidation in the Sphagnum moss microbiome. Global Change Biology. (2023).

Aerial Photo: Hanson, P.J., M.B. Krassovski, and L.A. Hook. 2020. SPRUCE S1 Bog and SPRUCE Experiment Aerial Photographs. Oak Ridge National Laboratory, TES SFA, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A. https://doi.org/10.3334/CDIAC/spruce.012 (UAV image number 0050 collected on October 4, 2020).

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Writer: Audra Davidson
Communications Officer II, College of Sciences

Editor: Jess Hunt-Ralston
Director of Communications, College of Sciences

Feb. 06, 2023
A range of tree-covered mountains stand beneath a bright blue sky

Plants, like animals and people, seek refuge from climate change. And when they move, they take entire ecosystems with them. To understand why and how plants have trekked across landscapes throughout time, researchers at the forefront of conservation are calling for a new framework. The key to protecting biodiversity in the future may be through understanding the past.

Jenny McGuire, assistant professor in the Schools of Biological Sciences and Earth and Atmospheric Sciences at Georgia Tech, spearheaded a special feature on the topic of biodiversity in The Proceedings of the National Academy of Sciences along with colleagues in Texas, Norway, and Argentina. In the special feature, “The Past as a Lens for Biodiversity Conservation on a Dynamically Changing Planet,” McGuire and her collaborators highlight the outstanding questions that must be addressed for successful future conservation efforts. The feature brings together conservation research that illuminates the complex and constantly evolving dynamics brought on by climate change and the ever-shifting ways humans use land. These factors, McGuire said, interact over time to create dynamic changes and illustrate the need to incorporate temporal perspectives into conservation strategies by looking deep into the past.

One example of this work highlighted in the journal is McGuire’s research about plants in North America, which investigates how and why they’ve moved across geography over time, where they’re heading, and why it’s important.

“Plants are shifting their geographic ranges, and this is happening whether we realize it or not,” McGuire said. “As seeds fall or are transported to distant places, the likelihood that the plant’s seed is going to be able to survive and grow is changing as climates are changing. Studying plants’ niche dynamics over thousands of years can help us understand how species adapt to climate change and can teach us how to protect and maintain biodiversity in the face of rapid climate change to come.”

Climate Fidelity: A New Metric for Understanding Vulnerability

The first step is to understand which type of plants exhibit what McGuire terms “climate fidelity,” and which do not. If a plant has climate fidelity, it means that the plant stays loyal to its preferred climatic niche, often migrating across geographies over thousands of years to keep up with its ideal habitat. Plants that don’t exhibit climate fidelity tend to adapt locally in the face of climate change. Being loyal to one’s climate, it turns out, doesn’t necessarily mean being loyal to a particular place.

To investigate the case of trees, McGuire and former Georgia Tech postdoctoral scholar Yue Wang (associate professor in the School of Ecology at Sun Yat-sen University in China) studied pollen data from the Neotoma Paleoecology Database, which contains pollen fossil data from sediment cores across North America. Each sediment core is sampled, layer by layer, producing a series of pollen data from different times throughout history. The data also contains breakdowns of the relative abundance of different types of plants represented by the pollen types – pine versus oak versus grass, for example – painting a picture of what types of plants were present in that location and when.

McGuire and Wang looked at data from 13,240 fossil pollen samples taken from 337 locations across the entirety of North America. For each of the 16 major plant taxa in North America, they divided the pollen data into six distinct chunks or “bins” of time of 4,000 years, starting from 18,000 years ago up to the present day. Wang used the data to identify all climate sites containing fossil pollen for any individual type of tree – such as oak, for example – for each period. Then, Wang looked at how each tree’s climate changed from one period to the next. Wang did this by comparing the locations of pollen types between adjacent time periods, which enabled the team to identify how and why each type of tree’s climate changed over time.

“This process allowed us to see the climate fidelity of these different plant taxa, showing that certain plants maintain very consistent climatic niches, even when climate is changing rapidly,” Wang said.

For example, their findings showed that when North American glaciers were retreating 18,000 years ago, spruce and alder trees moved northward to maintain the cool temperatures of their habitats.

Crucially, McGuire and Wang found that most plant species in North America have exhibited long-term climate fidelity over the past 18,000 years. They also found that plants that migrated farther did a better job of tracking climate during periods of change.

But some plants fared better than others. For example, the small seeds of willow trees can fly over long distances – enabling them to track their preferred climates very effectively. But the large seeds of ash trees, for example, can only be dispersed short distances from parent trees, hindering their ability to track climate. Habitat disruptions from humans could make it even more difficult for ash trees to be able to take hold in new regions. If there are no adjacent habitats for ash trees, their seeds are under pressure to move even farther – a particular challenge for ash, which slows their migration movements even more.

Protecting the Fabric of Life

On the bright side, by identifying which plants have historically been most sensitive to changing climates, McGuire and Wang’s research can help conservation organizations like The Nature Conservancy prioritize land where biodiversity is most vulnerable to climate change.

As a final step, McGuire and Wang identified “climate fidelity hotspots,” regions that have historically exhibited strong climate fidelity whose plants will most urgently need to move as their climates change. They compared these hotspots to climate-resilient regions identified by The Nature Conservancy that could serve as refuge areas for those plants. While plants in these resilient regions can initially adapt to impending climate change by shifting their distributions locally, the plants will likely face major challenges when a region’s climate change capacity is exceeded due to lack of connectivity and habitat disruptions from humans. Refining these priorities helps stakeholders identify efficient strategies for allowing the fabric of life to thrive.

“I think that understanding climate fidelity, while a new and different idea, will be very important going forward, especially when thinking about how to prioritize protecting different plants in the face of climate change,” McGuire said. “It is important to be able to see that some plants and animals are more vulnerable to climate change, and this information can help build stronger strategies for protecting the biodiversity on the planet.”

 

Citation: Yue Wang, Silvia Pineda-Munoz, and Jenny L. McGuire, "Plants maintain climate fidelity in the face of dynamic climate change." PNAS (2023).

DOI: doi.org/10.1073/pnas.2201946119

 

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Catherine Barzler, Senior Research Writer/Editor

Dec. 07, 2022

For marine scientist, climate activist, and Tech alumnus Albert George (MS HSTS 2009), the fight against climate change is also a fight for home. 

Now, what started as a citizen science initiative led by George has turned into a $2.6 million National Fish and Wildlife Association effort to restore degraded salt marshes in Charleston, South Carolina. As part of the project, Joel Kostka, professor and associate chair of Research in the School of Biological Sciences, will lead a team of researchers to not only monitor these restoration efforts, but gain insights into why the marshes degraded in the first place — and how to prevent it from happening in the future.

Over the past three years, Kostka, who has a joint appointment in the School of Earth and Atmospheric Sciences, has worked with SCDNR and Robinson Design Engineers, a local firm co-led by Tech alum Joshua Robinson (CEE 2005), to develop engineering and design plans for the restoration of the salt marshes.

“That project went really well,” shared Kostka, “and now we have developed engineering and design plans for the actual restoration as we are moving forward with the next phase.”

Work for the current phase of the project is set to begin soon. Over the next four years, community volunteers will work to plant marsh grasses, restore oyster reefs, and excavate the tidal creeks that supply the marsh with sea water. 

“Because if we don't do this work,” George shared, “then basically it means a place that I grew up in and a place that I call home will no longer exist.”

Read more about the collaborative effort and the community that started it all in the College of Sciences newsroom.

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Audra Davidson, College of Sciences

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Jess Hunt-Ralston
Director of Communications
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Oct. 04, 2022

Joel Kostka will soon receive $3.2 million from the Department of Energy (DOE) to build upon research that has ranged from northern Minnesota peat bogs to coastal Georgia wetlands, all to learn how climate change impacts soils and plants that trap greenhouse gasses — and whether some of those plants could end up as eco-friendly biofuels.

Kostka, a professor and associate chair of research in the School of Biological Sciences with a joint appointment in the School of Earth and Atmospheric Sciences, will receive funding as part of a wider $178 million dollar DOE effort to advance sustainable technology breakthroughs that can improve public health, help address climate change, improve food and agricultural production, and create more resilient supply chains. The 37 new projects also include efforts to engineer plants and microbes into bioenergy and improve carbon storage. 

Kostka’s wetlands research will continue in the salt marshes off Georgia’s coast, where his team has already conducted studies on the microbial life that benefits Spartina cordgrass in those areas, helping to strengthen resilience of the plant to sea level rise and catastrophic storms.

The DOE’s funding initiative is split into four groups. Kostka’s studies will focus on the role of microbiomes — all the microorganisms living in a particular environment — in the biogeochemical cycling of carbon in terrestrial soils and wetlands by using genomics-based and systems biology. 

Other research areas involve renewable bioenergy and biomaterials production; quantum-enabled bioimaging and sensing for bioenergy, and research to characterize gene function in bioenergy crop plants.

“Our project seeks to understand the controls of soil organic matter degradation and the release of greenhouse gasses, both of which are largely mediated by microbes” Kostka said. “And then also, as we've been studying for many years now, how climate drivers — principally the warming of ecosystems and carbon dioxide enrichment in the atmosphere — limit greenhouse gas release to the atmosphere. How might changes in plant and microbial communities lead to climate feedbacks, thereby accelerating the release of greenhouse gasses from soil carbon stores?”

That question has driven much of Kostka’s research team in the past as they focused on how soil microbes break down biomasses like woody plants and peat mosses, at an Oak Ridge National Laboratory facility in northern Minnesota called Spruce and Peatland Responses Under Changing Environments (SPRUCE). Kostka’s team is using genomics to study all the genes that code for microbial enzymes that decompose biomass in soil and how plants, which are also changing with climate, impact microbiomes by providing carbon sources that fuel microbial activities. In particular, the work is focused on lignocellulose or lignin, which gives plants their rigidity or structure and arguably comprises the most abundant renewable carbon source on the planet.

“We're just at the point now where we finally have the tools to unlock the black box of soil microbiology and chemistry,” Kostka said. “Recent advances in sophisticated analytical chemistry methods used to quantify microbial metabolites along with improved metagenome sequencing approaches enable us to better uncover metabolic pathways.”

Kostka will serve as principal investigator of the research team for the grant. That team includes School of Biological Sciences researchers Caitlin Petro, research scientist, and Katherine Duchesneau, a third-year Ph.D. student; co-principal investigator Kostas Konstantinidis, Richard C. Tucker Professor in the School of Civil and Environmental Engineering; Rachel Wilson, research scientist, Florida State University; Malak Tfaily, associate professor, University of Arizona; and Chris Schadt, senior staff scientist, Oak Ridge National Laboratory. 

Unlocking the “enzyme latch” hypothesis

As part of his new research, Kostka will revisit what scientists call the “enzyme latch” hypothesis. This could help uncover the mechanisms by which soils and plants capture harmful greenhouse gasses, and what prompts their release into the atmosphere.

The idea behind this hypothesis is that when soils are wet, they lack oxygen, which suppresses a specific class of enzymes, oxidases, that catalyze the beginning steps in the microbial breakdown of organic compounds produced by plants in soil. When oxidases are suppressed, the breakdown products of lignin, phenolic compounds, accumulate and poison the rest of the microbial carbon cycle.  Thus a single class of enzymes may be responsible for keeping greenhouse gasses like carbon dioxide and methane captured within the soil.

“The climate linkage here is that it's thought that as the climate warms, we'll get more greenhouse gas production, because simply it'll be warmer, and microbial enzymes work faster at higher temperature. But then also, in wetlands in particular, the hypothesis is that as wetlands warm, they're going to dry out. And so when a wetland dries out, you're going to get more injection of oxygen-rich air into the soil, which would then accelerate the breakdown of organic matter.”

When that happens, it could also mean different plants having an impact on carbon storage and the breakdown of biomass. “As wetlands dry out, plant communities in northern peatlands where most of Earth’s soil carbon is stored, are expected to shift from a dominance of mosses, which do better when it's wet — to woody plants, shrubs, and trees that do better with less water, when it's drier. That would in turn potentially spark the release of more reactive carbon compounds from plant roots — mosses don’t have roots — which would likely accelerate organic matter decomposition and the production of more greenhouse gas in a feedback loop with climate.”

Kostka’s research may also help to develop new approaches for converting woody biomass into potential alternative energy sources. “To make our society more sustainable, we have to basically recycle everything, or reuse as much as we can. And that includes the biomass from plants that can be grown on more arid lands that are less suitable for food crops,” he said, referring to plant-based materials that can be used to produce biofuels and bioenergy. “And so the DOE is leading research efforts to understand the controls of biomass degradation in plants such as switchgrass and poplar.” 

Kostka and Konstantinidis will develop a database of genes that code for the breakdown of lignocellulose and lignin, compounds that largely make up plant biomass and for which metabolic pathways of degradation have been elusive. Kostka and his colleagues will also have access to the extensive resources of the DOE Genomic Sciences program, including a collaboration with the agency’s Joint Genome Institute.

“We hope that information generated from our project can be used to improve methods for breaking down woody biomass so that it can be used in a sustainable way to produce biofuels,” Kostka said. 

Public abstract of Department of Energy grant DE-SC0023297

About Georgia Tech

The Georgia Institute of Technology, or Georgia Tech, is a top 10 public research university developing leaders who advance technology and improve the human condition. The Institute offers business, computing, design, engineering, liberal arts, and sciences degrees. Its nearly 44,000 students representing 50 states and 149 countries, study at the main campus in Atlanta, at campuses in France and China, and through distance and online learning. As a leading technological university, Georgia Tech is an engine of economic development for Georgia, the Southeast, and the nation, conducting more than $1 billion in research annually for government, industry, and society.

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Writer: Renay San Miguel
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404-894-5209

Editor: Jess Hunt-Ralston

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