Sherwin (Sam) Lehrer, biophysical chemist, emeritus Senior Research Scientist at the Boston Biomedical Research Institute (BBRI), and Principal Associate in Neurology, Harvard Medical School, died on March 17th, 2026. He was 91.

Sam was born in Brooklyn, NY, on April 2nd, 1934, to Tillie Schwartzdorf (born in Poland), a homemaker, and Harry (Tzvi Hirsch) Lehrer, a kosher butcher and owner of Lehrer's Delicatessen on the boardwalk at Rockaway Beach, NY.

At age 14, Sam's mother died, and his father remarried, to Fritzi Klein Goldstein of Pittsburgh, PA. Sam completed high school in New York, and then moved to be with his new family, including two younger step-brothers, Joe and Ron Goldstein. Sam attended University of Pittsburgh for his BA degree (class of 1956), and then University of California at Berkeley for a PhD in Chemistry (class of 1961). There he met Liane Reif, a fellow student, also from Brooklyn (born in Vienna, Austria), whom he followed back East and married. They soon settled in Lexington, MA, early members of the Peacock Farm Association, an idealistic modernist community, to raise their children. In the early 1970s, Sam began working at BBRI, alongside Liane, who worked in the same building at the Schepens Eye Research Institute. He stayed until his retirement, and BBRI's closure, in 2013.

His scientific career was dedicated to studying the basic mechanisms underlying muscle function, with a particular interest in "his favorite molecule", the protein tropomyosin. His contributions lie at the intersection of fluorescence methodology and muscle protein biophysics, and help to elucidate the molecular basis of muscle regulation. His pioneering work, supported by major NIH and NSF grants, both advanced the fundamental understanding of protein dynamics and provided a framework for linking molecular defects to muscle disease. He is remembered by his former international colleagues and supervisees as a brilliant, passionate scientist and an exceptional mentor, who welcomed many international students and postdoctoral fellows in his BBRI research laboratories in downtown Boston and later Watertown, MA, hosting them for Thanksgiving and Passover meals at the family home in Lexington, and for summer barbeques and swims at the neighborhood pool.

Sam was an avid ballroom dancer, photographer, biker, swimmer, and traveller. Together with his wife Liane he was a longstanding member of the Boston Waltz Evening Society, and taught dance at both of the retirement communities he lived in during his later years. He made two round-the-world trips, in 1962 with Liane, and again in 1978 with their children. Once his grandson Huckleberry arrived, he delighted in activities and later travels with him, going sea kayaking and doing a community theater production together where Sam dressed up as an alligator.

He was kind, generous, curious, philosophical, iconoclastic, and fun-loving, both gentle and stoic. A lover of nature, music, art, science, animals and young people, he had a twinkle in his eye, delighting in being the free-thinker who posed provocative questions to stir things up among family and friends. Along with being a devoted father and fully equal co-parent with Liane, Sam was also a surrogate father and grandfather figure to a number of family friends, who cherished his warm and offbeat guidance as he presided over their events and rituals. He was a deeply dedicated care-taker of Liane during the many years she suffered with Alzheimer's when they lived at Newbridge-on-the-Charles, where he also befriended the oldest members of the community and supported them as a personal shopper and tech-support guru. A number of neighbors at Brookhaven in Lexington, where he lived since 2021, recalled how his cat, Babka, would go out to the courtyard through the small door that he had installed, to catch mice and bring them back. Sam would put them in a glass, take them to the nearby woods, and set them free.

Sam never thought of himself as old. In the months prior to his death he was still corresponding with younger colleagues about research questions and organizing billiards clinics at the residence – especially teaching the women, who hadn't grown up with the game, how to play on the pool table whose purchase he had campaigned for. In summer 2025, despite cardiac arrhythmia, diminished lung capacity, and intense back pain he swam out to, climbed up on, and leapt off the floating dock at Squam Lake in New Hampshire. A month before his passing he was planning a European river cruise to take with his daughter, and purchased a fancy color printer for his photographs. Two weeks prior he was having a beer at Legal Sea Foods, enjoying spicy ramen at a local Japanese restaurant, and thinking about getting a recumbent bicycle. He had been reviewing melodies for the Brookhaven Passover seder, which he was to help lead on April 1st.

In the wee hours of Tuesday, March 17th, he fell asleep on his couch with his son by his side, holding his hand, and did not wake. He is buried alongside his wife Liane Reif-Lehrer, her brother, the physicist Frederick Reif, and their mother, Clara Gottfried Reif, in Mount Auburn Cemetery in Cambridge, MA.

Sam is survived by his children, Damon Lehrer of Lexington, MA, an artist and founder of the Boston Figurative Art Center in Somerville, MA, and Erica Lehrer, a cultural anthropologist and professor at Concordia University, Montreal; his daughter-in-law Aimee LeBrun of Lexington, MA, and grandson Nathan Huckleberry LeBrun Lehrer (currently at McGill University, Montreal); his step-brother Joseph Goldstein of Pittsburgh (with Joe's children Ellen Beth and Bennett and grandchildren Zachary and Tyler Sikov and Andrew and Jeremy Goldstein); and step-sister-in-law Sally Goldstein of Berkeley, CA. He was predeceased by his stepbrother Ron Goldstein.