
Anherutowa Calvo: Building a toolbox of skills, in energy and bioengineering
For Anherutowa Calvo, energy and environmental issues have always been top of mind.
Growing up on the island of Guam, the sophomore chemical and biological engineering student reckoned with a legacy of environmental burdens, including the conversion of ancestral lands into military bases and training areas for the United States. The U.S. Department of Defense owns about 25% of the land on Guam, which is an unincorporated United States territory.
Calvo said that the military’s use of culturally significant lands — lands that had been in the families of Guam residents for generations — and the resulting pollution “was really disorienting for my family and others.”
In response, Calvo spent his high school days organizing coastal cleanups, leading tree plantings, and meeting with youth groups across Guam to chart a just and sustainable pathway for the island.
And in 2022, Calvo represented Guam at the FIRST Global Challenge in Geneva, Switzerland, a robotics competition that brought together young people from over 180 nations to develop technologies for carbon capture and storage. Calvo said the competition was a way to combine environmental protection with a childhood hobby of tinkering with LEGOs. It also showed him that technological development could be positive and transformative.
“It was like a light bulb went off: I could actually build things that made the world better,” he said. “Suddenly, the opportunities seemed limitless.”
Calvo entered Princeton the following year energized, drawing from his experiences at the competition and growing up on Guam. After his first year, he saw an opportunity to unite his interests in an internship through the Andlinger Center for Energy and the Environment. Working with Jonathan Conway, an assistant professor of chemical and biological engineering, Calvo explored the bacteria Caldicellulosiruptor bescii and its promising applications for biofuels. Biofuels are liquid fuels derived from renewable sources, such as plants and algae, that could offset or replace fossil fuel usage in hard-to-decarbonize transportation applications.
While offering several environmental advantages, producing biofuels economically is a challenge. Plants are rich in lignocellulose, one of the primary components of a plant’s cell wall that gives a plant its structural support. While helpful for growing plants, lignocellulose is difficult to break down and convert into valuable products. Converting plant matter to biofuels typically requires extensive pretreatment to separate it into components that biofuel-producing microorganisms can digest, which costs time and money while creating substantial waste.
C. bescii, first isolated in 1990 from a natural hot spring in Kamchatka, Russia, can degrade and convert lignocellulose into valuable products with minimal pretreatment, making it an attractive option for producing biofuels. However, due to its remote origin and relatively recent discovery, many unknowns exist about how the bacteria degrades, processes, and transports different sugars.

Calvo spent the summer studying metabolic processes in C. bescii, working alongside his graduate student mentor Hansen Tjo. Calvo and Tjo designed and inserted vectors that disrupt, or knock out, the function of specific genes in C. bescii, including ones that code for sugar-degrading enzymes and sugar-transporting proteins. By studying the performance of C. bescii with various genes knocked out, Calvo could figure out how different proteins break down and transport sugars.
“We still need to go through the process of sorting out the metabolic pathways of C. bescii before we can optimize it to produce the fuels we want,” Calvo said. “We don’t want the bacteria to waste energy processing and transporting undesirable sugars. We also want to find the optimal pathways for C. bescii to generate the most desirable products.”
Like the LEGOs he played with as a kid, Calvo said his work in the Conway lab taught him how bioengineering can provide building blocks for valuable products and innovative processes. It also gave him an understanding of what it means to contribute to scientific research, as well as how to design and carry out rigorous experiments.
Calvo said he especially appreciated how the skillset he gained while working on C. bescii for energy applications is transferable to the career that he plans to pursue in pharmaceutical research and development.
Now, Calvo hopes to complement the experimental skillset he gained as an Andlinger Center intern with experience in computational modeling and simulations. He said the work of Jerelle Joseph, an assistant professor of chemical and biological engineering and the Omenn-Darling Bioengineering Institute whose work on biomolecular condensates he learned about during his internship, inspired him in its use of emerging AI tools to make meaningful advances in how we understand living cells.
In addition to his research experience in the Conway lab, Calvo is exploring his childhood affinity for robotics as a team lead for the Princeton University Robotics Club. The team is developing a prosthetic hand that can operate using the residual electricity from muscle movements in the arm. Afterward, they hope to implement a similar system in a prosthetic human heart.
“Having the chance to do a bit of everything and explore my interests through hands-on experiences has been incredibly helpful as I think about what impact I want to make on the world,” Calvo said.
Calvo’s internship was supported by the Peter B. Lewis Fund for Student Innovation in Energy and the Environment and the LENS Funding Initiative.