Unraveling the secrets of ancient microorganisms has taken Luke McKay to a Canadian glacier, the depths of an ocean and the hot pools of Yellowstone National Park.
Now the Montana State University researcher has received a NASA Postdoctoral Fellowship from the NASA Astrobiology Institute to expand his work in Yellowstone. It’s the same prestigious award his adviser, Eric Boyd, received seven years ago and which helped to propel his academic career.
“I was very excited and surprised,” said McKay, who came to MSU specifically to work with Boyd. “With funding from NASA, I’m able to pursue this fascinating research in a more directed and supported fashion.”
“This is big news, and I am very proud of him,” Boyd said. “This fellowship provides a mechanism for Luke to interact and work with some of the world’s best scientists while studying a very interesting and newly discovered metabolism.”
As a postdoctoral research associate in MSU’s Department of Microbiology and Immunology in the College of Agriculture and the College of Letters and Science,McKay studies microbes that live under extreme conditions in the hot springs in Yellowstone National Park and beneath Robertson Glacier in Alberta, Canada. Among other things, he wants to understand the metabolism of modern day ancestors of what many believe to be the most primitive microorganisms on Earth — methanogens, McKay said.
Methanogens produce methane gas while using carbon dioxide and hydrogen for growth. Genetic studies have shown that the methanogens McKay studies are descendants of primitive lifeforms that evolved greater than 3.5 billion years ago. Now it is known that these ancient methanogens may have used a more powerful energy source than previously thought — oxidized iron, or rust.
“I am investigating what may be one of the oldest life-sustaining processes on Earth,” McKay said. “… This unique metabolic strategy is a strong candidate for the earliest of biological processes, both from a geochemical and microbiological perspective.”
His one-year fellowship, which could be renewed for a second year, will allow him to perform detailed studies of modern-day organisms that are sustained by what is likely an ancient mode of metabolism, McKay said. He will collect organisms from the hot springs in Yellowstone, grow them in a laboratory and give them oxidized iron to process. His studies will take him to the University of Wisconsin’s Department of Geosciences, where he will work with collaborators to study and compare aspects of iron and carbon produced by these cultures with iron and carbon identified in rocks that are greater than 3 billion years old.
“The details of this microbial process, for example, how these organisms use iron to create extra energy, have so far eluded our understanding,” McKay said.
The outcome has implications for understanding the processes that support life on Earth, as well as improving predictions of where to look for life on other planets, such as Mars, McKay said. It’s a topic of special interest to NASA, as well as McKay.
“NASA is very interested in ancient evolutionary processes, the origins of life and the evolution of life elsewhere,” McKay said. “Improving our understanding of how these early-evolving organisms grow gives us a lot of information about where else they might exist or be able to exist.”
McKay’s interest in astrobiology grew from his time as a student at the University of Alabama at Birmingham and studying for a semester in Santiago, Chile. While taking a genetics class in Chile, the Alabama native compared Spanish and English textbooks, so he could better understand the material. In the process, he became so interested in molecular biology and evolution that he decided to pursue those subjects in graduate school.
He earned his master’s and doctoral degrees at the University of North Carolina at Chapel Hill, with his fieldwork taking him to the hydrothermal vents in the Guaymas Basin. The basin is the largest in the Gulf of California.
To learn more about astrobiology – the study of the origin, evolution, distribution and future of life in the universe – McKay came to MSU in January this year to study with Boyd, an assistant professor in MSU’s Department of Microbiology and Immunology, a NASA Early Career Fellow and former NASA Astrobiology Institute Postdoctoral Research Fellow.
Last fall alone, Boyd became deputy director of a new $7 million project funded by NASA to investigate the origin and future of life in the universe. One of his graduate students,Max Amenabar, spent six weeks on a research ship best known for carrying researchers to the sunken Titanic in 1985. Amenabar was part of a team looking for microbial life in 3-million-year-old sediments beneath the floor of the North Atlantic Ocean.
“I came here because he is very successful and is good at what he does, and he does really awesome stuff,” McKay said of Boyd.
