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Meet Joan Marcano

Joan Marcano is passionate about keeping waterways pure, a drive that connects his work in NREL's National Bioscience Center with his time in Colorado's world-class Gold Medal waters. The Director's Fellow postdoc took up fly-fishing about five years ago while in grad school at the University of Colorado-Boulder. "It's a hobby that fit me. I enjoy being in nature, and fly-fishing gives me a chance to explore new places in Colorado and new rivers."

NREL researcher shown half in the laboratory and half in a river holding a fly fishing rod.
Riboswitches + Rainbow Trout

Mastering the sport is a lot like succeeding in the lab: it takes focus as well as trial-and-error experimentation. "Another thing that attracted me to the sport is that there are technical aspects. I had to read about aquatic insect life, and how does that happen in the river. That's basically what you must imitate when fly fishing. You 'match the hatch' and find out what insects are in there at any given point, and how do you mimic with flies," Joan says.

Mastering the sport takes perseverance. "It's a steep learning curve. New fishers go out three or four times and don't catch a fish, until they finally get one. It's an energy barrier," he says—one that Joan has overcome. Fly-fishing is a sport that draws on the scientific mind. "You are kind of solving a puzzle every time you go to the river. There are so many different variables that can be affecting what the fish are feeding on. You have to put them all together until it finally works."

Now he is teaching others to angle—and after spotting other cars at NREL with fishing-rod racks, he plans to ask the car owners to go in search of rainbow trout.

Engineering bacteria in search of a better world

At NREL, Joan currently engineers bacteria—in particular Clostridium thermocellum—to make different products like hydrogen. "I have to put all these pieces together as well—what sort of genetic elements and what sort of genes am I going to put in combination. I might try different variations and iterations—just like fishing. On the river, you keep changing your flies, extending your leader, or sinking it deeper," he says.

Part of the research goal is to utilize waste biomass by converting it into a valuable product. "The challenge is that this biomass, and the sugars present in it, comes in the form of cellulose," he says. "It is a very hard compound to degrade. We have identified the organisms that naturally can degrade this, and in turn can ferment it into ethanol or hydrogen, or potentially other products—which is our goal."

Joan's focus is to create novel ways to control the C. thermocellum gene expression, using riboswitches, which are natural regulatory RNAs, and trying to repurpose them as metabolic engineering tools. "We need to establish some genetic tools first before we can efficiently genetically engineer this organism to produce higher amounts of hydrogen." That can help make the transformation of biomass more economically feasible and that process more efficient.

"I think technologies we are developing here will have an impact on environmental conservation, which ties back to my passion about saving water and rivers—I want a world with enough pure water where I can bring up my daughter and take her fishing."

And it's not just about him. Joan, who is from Puerto Rico, believes renewable energy technologies can help communities in his home that are affected by natural disasters, but also around the world. He thinks that NREL's research into renewables can help provide a measure of social justice for communities without basic electricity. "For example, you can build a microgrid that would plug in solar or gas from the microorganisms I'm studying," he says. Contributing in that way would make him proud—as proud as he'll be when his daughter lands her first trout fly-fishing with him.