Ask Caltech microbiologist Dianne Newman what she does for a living, and she’ll answer with a chuckle: “I study weird forms of metabolism.” She has spent a career studying the strange ways in which microscopic organisms get the food and energy they need in environments without oxygen — a quest that has taken her from geology to biology and from Earth’s most ancient origins to the pathogens of today.

That dizzying journey proves how interconnected past and present can be. And it attracted the attention of the MacArthur Foundation, which just named her one of its 2016 fellows.

Newman uses really old microbes to help tell the story of new ones, and vice versa. “Our research goes in both directions,” she explained. It all starts with really old rocks, which contain traces of Earth’s oldest organisms within.

“It’s not the same as finding a dinosaur,” Newman said. While large animals of yore left behind fossilized bones, smaller organisms left their signatures in a much tinier form: molecular remnants and inorganic byproducts created billions of years ago that can be found only in ancient outcrops of rocks.

There, you’ll find 2-methylhopanoids — a somewhat intimidating name for what are, in essence, the fossils of really old organisms. “It’s essentially just a different kind of steroid that is made by lots of bacteria,” she said. 2-methylhopanoids hang around in rocks that are more than 1.5 billion years old, forming a tiny fossil record that could one day unlock the secret of just how early microbes helped form Earth itself.

“It’s a tantalizing problem, because you don’t have a time machine,” she said. She may not have a device that can blast her to the past, but she’s got two things going for her: modern-day chemical and genetic tools and bacteria that act like their ancestors. Using both, she’s helping piece together a picture of how ancient microbes transformed an Earth with no atmosphere into one filled with oxygen.

That line of inquiry has also taken her in a seemingly different direction — deep into the microbes that put people with a disease like cystic fibrosis at risk or contribute to their symptoms. If the two seem unrelated, think again. “It’s a very simple leap,” Newman explained. When microbes clump together into biofilms — like the slimy films that coat your teeth or stick to wounds — the ones at the outside of a community rapidly consume all available oxygen. The ones inside the community are left in an anaerobic environment similar to the one experienced by those early Earth-dwelling microbes.

“Microbes have had at least a billion if not a billion-and-a half-years to figure out ways of generating energy in the absence of oxygen,” she said. “It’s not surprising that those metabolisms would still be of relevance today.”

Ultimately, Newman hopes that her work on the metabolisms of long-gone microbes could reveal insights about modern-day organisms that cause chronic infections. “The path is clear,” she said. Soon, with the help of what she knows about how ancient anaerobic microbes worked, she’ll start to test proteins that could keep biofilms full of pathogenic bacteria from plaguing patients with cystic fibrosis.

Newman isn’t yet sure how she’ll leverage the $625,000 stipend that comes along with the “genius” grant, but she wants to put what she calls her “five seconds of fame” to good use. “In those five seconds, I hope to spread the word that it’s possible, regardless of your socioeconomic background, to become a scientist,” she said.

So what motivates her on the days when the connections between really old rocks and cystic fibrosis seem less than clear? Newman laughs again. “My mom would say I have an innate curiosity and maybe a stubbornness,” she said. “I also have a certain underlying confidence that I’m not crazy.” It’s that confidence that pushes her to keep looking for the connections between geology and biology, ancient and modern. “These are different contexts, but at the core level the challenges are similar,” she said. “What we care about matters.”

Correction: An earlier version of this post referred to bacteria that cause cystic fibrosis. Cystic fibrosis is genetic – the bacteria are associated with the disease because they cause dangerous infections in cystic fibrosis patients. This has been corrected. 

Erin Blakemore (@heroinebook) is a freelance journalist from Boulder, Colo. She is the author of "The Heroine’s Bookshelf" (Harper). 

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