Biophysical Society Bulletin | September 2025

Biophysicist in Profile

Pablo Peixoto Area of Research Mitochondrial signaling, with a focus on channels

Institution Baruch College, City University of New York

At-a-Glance

In the bustling kitchen of his childhood home in Brazil, while his single mother rushed to prepare meals for four children before work, young Pablo Peixoto bombarded her with an endless stream of questions. “I was that annoying kid who wouldn’t stop asking ‘what?,’ ‘why?,’ and ‘how?,’” he recalls. This insatiable curiosity extended from the kitchen to the classroom, where he peppered teachers and peers with questions during lessons or presentations, and has since carried him through to his career as a biophysicist. “I stopped asking why, but I kept asking what and how.”

Pablo Peixoto

Pablo Peixoto ’s journey began far from the ivory towers of ac ademia. His childhood was spent moving around Brazil, from a shanty home in Sobradinho to the outskirts of Brasília, and to Rondônia in the Amazonian region, from where his mother had migrated as part of the candango wave that built Brazil’s capital. The family eventually settled in Uberlândia, where he would come of age and begin his academic journey. Peixoto was the first in his family to attend college, though he notes that he was inspired to study science by his uncle, Chico: “In another life he might have been an engineer,” Peixoto reflects. His mother cleaned houses during his childhood, later starting a business and eventually earning her high school diploma and a degree in history. She now works as an elementary school administrator. At the Universidade Federal de Uberlândia, Peixoto began his scientific career in an ecology and animal behavior laboratory under Kleber Del Claro , studying the complex tripartite inter actions between ants, aphids, and plants. His research focus then shifted to the honeybee brain, where he investigated myosins under the mentorship of Foued Salmen Espíndola , who would guide both his undergraduate and master’s the ses. The pivotal moment that would set him down his career path came during his senior year. When he discovered a flier from the Agencia Española de Cooperación Internacional para el Desarrollo (AECID) advertising research internships across Spain, one opportunity stood out—not for its appeal, but for its apparent lack thereof. “I applied for the one I assumed no one else would want: Mitochondrial Electrophysiology at the Universidad de Extremadura in Cáceres,” he explains. “I thought the title sounded intimidating and that people would rather pick Barcelona, Madrid, Salamanca, or Seville.” This calculated gamble paid off spectacularly. Cáceres, as Peixoto puts it, “became my point of no return.” The internship

introduced him to the fascinating world of mitochondrial elec trophysiology and to Marisa Campo , whom he fondly refers to as one of his two “scientific mothers.” After briefly return ing to Brazil to complete his master’s degree, he secured a CAPES-Humboldt Research Fellowship to return to Cáceres for his PhD under Campo’s guidance. His doctoral work established him as an expert in patch-clamping mitochondria, a rare and technically demand ing skill that would prove invaluable throughout his career. This expertise caught the attention of Casey Kinnally at the New York University College of Dentistry, who would become his second “scientific mother.” Despite not having published his thesis work at the time, Kinnally recognized Peixoto’s potential and recruited him for postdoctoral research. “It was serendipity,” Peixoto says of his entry into mitochon drial biophysics. “That AECID internship opened the door, but I stayed because Marisa and Casey saw something in me and nurtured it. I became a mitochondriac and never looked back.” The term “mitochondriac”—a playful portmanteau of mito chondria and maniac—perfectly captures Peixoto’s enthusi asm for these cellular powerhouses. In Kinnally’s lab, Peixoto dove into cancer research, studying how mitochondria release apoptotic signals and how this crucial process fails in malignant cells. “At the time, I had not yet published a paper from my thesis, but I had a rare techni cal skill and she gave me a chance to prove myself,” he recalls. That chance paid dividends: Five years and twelve papers later, he had established himself as a formidable researcher and moved to a new postdoc position in Giovanni Manfredi ’s laboratory at Weill Cornell, where he expanded his expertise from electrophysiology into metabolism. “Giovanni brought me in for patch clamping, but I left with a solid foundation in metabolism, thanks to working closely with Anatoly Starkov and others in the lab,” he notes.

September 2025

4

THE NEWSLETTER OF THE BIOPHYSICAL SOCIETY