December 12, 2024

Sustainable Energy from a Microscopic Source: Microbiologist Pursues Future Fuel Sources


Dr. Nicole Buan, NSRI Fellow and professor of biochemistry, in her lab at the University of Nebraska–Lincoln. –

Lincoln, Neb. —Dr. Nicole Buan has been planning ahead for a long time.

"I’ve always been thinking 20, 30, 50 years into the future, even as a teenager," she said. "I realized we need fundamental, basic research to build technologies that will only be seen decades from now, and I wanted to be one of the people who could bring us forward and make sure our fundamental understanding and knowledge was strong enough to base sustainable tech upon." 

During high school, Dr. Buan’s intense curiosity about the way the world works led her to study the microscopic processes that make cells work. She continued her pursuit of plant biochemistry at the University of Arizona where her advisor, Dr. Elizabeth Vierling, allowed her to be an independent researcher at a young age.

"Nicole is fiercely independent and highly organized. These are characteristics that have allowed her to pursue and succeed at unique lines of research," Dr. Vierling said. "She is pushing the envelope in her field, and I envision significant contributions not just to academic science, but also to global issues of climate change and sustainability."

While Dr. Buan initially considered pursuing virology in graduate school, she ultimately chose to pursue a doctorate degree in microbiology under the mentorship of Dr. Jorge Escalante at the University of Wisconsin-Madison. She focused her study on the biochemistry of vitamin B12 biosynthesis, choosing a technically daunting project and a supportive mentor that gave her an opportunity to develop expertise on a wide array of techniques. As a side project, Dr. Escalante introduced Dr. Buan to the study of methanogenic archaea — a field that combined her interest in the mechanics of the microscopic world with her desire to contribute to a more sustainable future. She followed up on her interest by studying with Dr. William Metcalf at the University of Illinois, where she trained on methanoarchaeal physiology as a postdoctoral fellow.

"I chose biofuels and bioenergy as a career path at a pretty early age because I sat down and thought about what critical needs our society is going to face, and where the gaps in our technology are if we’re going to meet those needs," Dr. Buan explained. 

Growing up in Honolulu, Hawaii, and later in Tucson, Arizona, Dr. Buan experienced how dependent human beings are on clean soil, clean water and healthy crops and animals to survive. As a child, she observed firsthand how pollution harms coral reefs and the marine life people depend on for food. She watched the famous tropical beach, Hanauma Bay, once crystal-clear and filled with colorful fish that could be fed by hand, become so choked with pollution that the authorities had to strictly limit access to allow the bay and the wildlife to recover. Today, Hanauma Bay is once again a thriving shallow reef ecosystem, although feeding the animals is no longer permitted.

As a teenager in Tucson, she regularly hiked desert trails amongst the cactus, creosote and rattlesnakes and celebrated every monsoon season when intense thunderstorms drench the cracked, dusty soil, bringing precious rain that plants, animals and humans ration all year to be able to survive.

These experiences engrained her desire to develop environmentally friendly technologies as well as faith that humans can find sustainable ways to coexist with nature.

"It’s the same in Nebraska," Dr. Buan explained. "It’s just baked into growing up in these places — you understand how we have to steward the environment. If we want to continue as a species, we have to work to protect our natural resources. It’s a fundamental driving factor for me. We need our products to rest on a sustainable bio-based economy."

Since she joined the University of Nebraska–Lincoln in 2010, Dr. Buan’s lab has contributed practical solutions toward her long-time goal, earning two patents for technologies that can enhance the production of renewable methane and isoprene, which could lead to the production of fuels such as natural gas and jet fuel. Two other pending patents focus on increasing crop growth for feed and fuel production. If these technologies can be developed further, they could help support the Nation’s energy independence and safe environment.

But technology can’t change the world if it can only be used once in a lab at an extraordinary cost. It needs to be accessible, cost-effective and reliable.

"We don’t have tech unless the economics work out," Dr. Buan explained.

Accomplishing this requires asking some challenging questions that she posed: "What do we need to learn to make biofuels more profitable and produced more inexpensively so they can be more widely adopted? Likewise, what are the concerns of the public that we hope will use this tech? It can be hard to get people to understand microbes — they’re so little, they’re invisible and oftentimes the public doesn’t understand how much we already rely on them."

The methanogenic archaea that are now the focus of much of Dr. Buan’s work are microorganisms that are the only known organisms to create methane — natural gas — as a byproduct of their metabolism. These organisms thrive in environments without oxygen and are found in places such as wetlands, landfills, deep water hydrothermal vents and the digestive tracts of many animals — including humans.

But despite humans carrying around a host of these creatures inside, the general public is mostly very unfamiliar with them, which can be a barrier to people understanding the value of studying them. There can even be some difficulty explaining her work to other microbiologists.

"Because the physiology of these microbes is so different and unique, it is often hard to explain to our peers why we chose to do an experiment, or how we can conclude this means that, because their knowledge is based on organisms such as E. coli or yeast, and it doesn’t apply to methanogens," she explained.

Fortunately, Dr. Buan is up for the challenge.

"I didn’t go into this field because I like easy things," she said. "When you’re studying these organisms, you have to keep abreast of what other people are doing in the much broader field of microbiology. The types of experiments we’ve done and the equipment we’ve used altogether gives us an interesting fundamental perspective."

That comprehensive perspective makes Dr. Buan an excellent translator between researchers in different fields — computer scientists, mathematicians and physicists. She is dedicated to her mission, up to the challenge of her discipline and an experienced collaborator — all of which make her an ideal fit for the National Strategic Research Institute (NSRI) at the University of Nebraska.

A University Affiliated Research Center designated by the U.S. Department of Defense, NSRI bridges the gap between national security threats and the academic researchers who can help solve them. Dr. Buan serves as an NSRI Fellow to help meet the needs across NSRI’s research portfolio, particularly chemical and biological threat detection and countermeasure development and food, agriculture and environment security.

"My NSRI colleagues and I have been discussing how we might recommend revisions to biosafety practices at the national level," Dr. Buan explained. "Bringing forth a sustainable bioeconomy will require engineering organisms, and we want to do that in a safe and secure way. It’s important that practitioners are involved in these discussions so we can develop policies and procedures that don’t impede research but provide assurance to those not involved that it’s safe, so it can be widely adopted."

Dr. Buan said NSRI has been a critical asset for bringing together researchers in different areas to focus on solving the Nation’s problems.

"It’s been an honor to be able to work with colleagues through NSRI who also care about environmental sustainability and food and ag security and think about how we could use our expertise to strengthen the energy, food and agriculture sectors,” she said.

Although Dr. Buan’s research has already shown considerable results, there is still much to learn regarding the fundamental aspects of methanoarchaea. Discovering more will take time, and that means the next generation of passionate, knowledgeable researchers will need to study these unusual organisms.

"It’s very important to recruit young people into this area of research," Dr. Buan said. "It will take a lifetime for them to develop into the scientists who solve problems we can’t see today. Let’s start training the next generation to take these things seriously early on and to always be using their research and technology for the good of humanity — in the U.S., but also across the world."

Fortunately, Dr. Buan has spent decades putting in the effort required to develop a fundamental understanding of how microbes work as well as preparing tomorrow’s promising researchers to turn that understanding into life-changing technology for years and decades to come. She’s working to develop the sustainable world she envisioned as a teenager — and the whole world stands to benefit.