Sidney Altman

Early life and education in Montreal and the United States

Sidney Altman was born on May 7, 1939, in Montreal, Quebec, to parents who were Jewish immigrants from Eastern Europe. His mother, Ray (Arlin), emigrated from Białystok, Poland, at the age of eighteen with her sister, learned English, and worked in a textile factory to fund bringing the rest of her family to Canada. His father, Victor Altman, was born in Ukraine, had worked on a Soviet collective farm, and was sponsored to come to Canada as a farm worker before running a small grocery store in Montreal. Altman later reflected that his parents' lives illustrated the value of a strong work ethic, teaching him that hard work in stable surroundings could yield rewards. As the family's financial situation improved, Altman was able to pursue a college education, leading him to leave Canada for the United States in 1958.

Altman enrolled at the Massachusetts Institute of Technology to study physics, and he was a member of the MIT ice hockey team during his undergraduate years. He received his Bachelor of Science degree from MIT in 1960 and then began graduate studies in physics at Columbia University. He spent 18 months in the Columbia program but left without completing a degree, citing personal concerns and a lack of laboratory opportunities for new graduate students. After some months, he shifted his academic focus entirely, enrolling as a graduate student in biophysics at the University of Colorado Medical Center. His Ph.D. project involved studying the effects of acridines on the replication of bacteriophage T4 DNA, and he earned his doctorate in 1967 under advisor Leonard Lerman.

Postdoctoral research and the path to discovery

After receiving his Ph.D., Altman followed his advisor Leonard Lerman to Vanderbilt University for a brief period as a researcher in molecular biology. His first major postdoctoral fellowship was in Matthew Meselson's laboratory at Harvard University, where he studied a DNA endonuclease involved in the replication and recombination of T4 DNA. A second fellowship at the MRC Laboratory of Molecular Biology in Cambridge, England, proved critical, as it was there he began the work that led directly to his Nobel Prize. At the MRC, with advice from John D. Smith and postdoctoral colleagues, Altman started investigating the enzyme RNase P. His earlier discovery of the first radiochemically pure precursor to a tRNA molecule was directly responsible for him securing an assistant professor position at Yale University in 1971, during a difficult period for academic hiring.

Academic career at Yale and Nobel Prize-winning work

Altman's career at Yale followed a standard academic trajectory, with promotions leading to a full professorship in 1980. He served as Chairman of his department from 1983 to 1985 and then took on the significant administrative role of Dean of Yale College from 1985 to 1989. On July 1, 1989, he returned full-time to his professorial duties, which included mentoring doctoral students such as Ben Stark. His research at Yale focused intensely on the ribonucleoprotein particle RNase P, which is involved in the maturation of transfer RNA molecules. The prevailing belief was that the protein subunit of this complex was solely responsible for its catalytic activity in bacteria.

During experiments reconstituting the RNase P complex in test tubes, Altman and his research group made a decisive discovery. They found that the RNA component of bacterial RNase P, in isolation, was sufficient for the enzyme's observed catalytic activity. This demonstrated that the RNA itself possessed catalytic properties, a finding that earned Altman the Nobel Prize in Chemistry in 1989, which he shared with Thomas R. Cech. Altman's later research expanded on this discovery, showing that in eukaryotic organisms, unlike in bacteria, the protein subunits of the RNase P complex are essential for its catalytic function. This work established the field of ribozyme research and changed fundamental understanding of RNA's biological roles.

Honours, awards, and society memberships

Sidney Altman's scientific contributions were recognized by his peers through election to several of the most prestigious scholarly societies in the United States. His election to the American Academy of Arts and Sciences as a Fellow in 1988 preceded the Nobel Prize announcement the following year. In 1990, he was elected a member of both the National Academy of Sciences and the American Philosophical Society, honours that reflect the broad significance of his work. These memberships, along with the Nobel Prize, represent the highest formal acknowledgments of a career dedicated to molecular biology.

• Nobel Prize in Chemistry, shared with Thomas R. Cech (1989)
• Fellow of the American Academy of Arts and Sciences (1988)
• Member of the National Academy of Sciences (1990)
• Member of the American Philosophical Society (1990)

Personal life, citizenship, and death

Altman married Ann M. Körner, daughter of Stephan Körner, in 1972, and the couple had two children, Daniel and Leah. Having lived primarily in the United States since leaving Montreal for MIT in 1958, Altman chose to become a naturalized U.S. citizen in 1984. He maintained dual citizenship, remaining a Canadian citizen throughout his life. In his later years, Altman continued his academic work as the Sterling Professor of Molecular, Cellular, and Developmental Biology and Chemistry at Yale. After a long illness, Sidney Altman died on April 5, 2022, in Rockleigh, New Jersey, at the age of 82.

Scientific publications and archival legacy

Altman authored numerous research papers that detailed his findings on RNA catalysis and RNase P, communicating the evidence for RNA's enzymatic role. His 1989 minireview, 'Catalysis by the RNA subunit of RNase P,' co-authored with several colleagues, served as a concise summary of the groundbreaking work at the time of the Nobel Prize. Nearly two decades later, his 2007 article, 'A view of RNase P,' published in Molecular BioSystems, demonstrated his continued engagement with the subject and its development. These publications form part of the essential literature for the study of ribozymes.

The Sidney Altman Papers are held as manuscript collection MS 1680 in the Manuscripts and Archives department of the Yale University Library. This archive provides a resource for historians of science. The collection includes his research notes and correspondence. These materials document his career from his early work to his later reflections on the field.

The impact and context of the ribozyme discovery

The discovery that RNA could act as an enzyme forced a major revision of biochemical principles, which had held that all enzymes were proteins. This finding provided strong support for the 'RNA world' hypothesis, which suggests that RNA-based life forms could have preceded DNA and protein-based life in early evolution. Altman's work on RNase P, along with Thomas Cech's independent work, created the entirely new field of ribozyme research, which explores RNA's dual roles as an information carrier and a catalyst. The practical applications of this knowledge extend into areas like gene therapy and the design of targeted molecular tools, as ribozymes can be engineered to cut specific RNA sequences. Altman's career, from Montreal to Yale and the Nobel podium, remains a prominent example of Canadian scientific excellence with a direct and measurable effect on modern biology.

Questions about Sidney Altman

What did Sidney Altman win the Nobel Prize for?

Sidney Altman shared the 1989 Nobel Prize in Chemistry with Thomas R. Cech for their independent discoveries of the catalytic properties of RNA. Altman's specific work demonstrated that the RNA component of the enzyme RNase P could catalyze chemical reactions on its own, proving that RNA could function as an enzyme, which he termed a ribozyme. This discovery challenged the long-held belief that only proteins could act as biological catalysts. It opened new avenues of research in molecular biology and theories about the origins of life.

Where was Sidney Altman born?

Sidney Altman was born in Montreal, Quebec, Canada, on May 7, 1939. His parents were Jewish immigrants from Eastern Europe. His mother was from Poland and his father from Ukraine. He grew up in Montreal, where his father ran a small grocery store. Altman later moved to the United States for university but maintained his Canadian citizenship alongside his later American citizenship.

Where did Sidney Altman work?

Altman spent the majority of his academic career at Yale University, where he joined the faculty as an assistant professor in 1971. He rose to become a full professor in 1980 and later served as the Sterling Professor of Molecular, Cellular, and Developmental Biology and Chemistry. He also held significant administrative roles at Yale, including Chairman of his department and Dean of Yale College. Prior to Yale, he conducted postdoctoral research at Harvard University and the MRC Laboratory of Molecular Biology in Cambridge, England.

What is a ribozyme?

A ribozyme is a ribonucleic acid (RNA) molecule that can catalyze specific biochemical reactions, similar to how protein-based enzymes function. Sidney Altman's Nobel Prize-winning research on RNase P provided the first clear evidence that RNA could possess such catalytic activity. The discovery of ribozymes revolutionized the understanding of RNA's biological roles, extending it beyond a mere carrier of genetic information. This finding has major implications for understanding fundamental cellular processes and the early evolution of life on Earth.

Was Sidney Altman a Canadian citizen?

Yes, Sidney Altman was a Canadian citizen by birth and maintained that citizenship throughout his life. He became a naturalized citizen of the United States in 1984, holding dual Canadian-American nationality. Although he lived and worked primarily in the United States after leaving Montreal to attend MIT in 1958, his Canadian origins remained a key part of his identity. He is celebrated as a Canadian Nobel laureate in science.

When did Sidney Altman die?

Sidney Altman died on April 5, 2022, in Rockleigh, New Jersey, United States, after a long illness. He was 82 years old at the time of his death. His passing was noted by the scientific community as the loss of a pioneering figure in molecular biology. His legacy continues through his foundational discoveries and the ongoing research in the field of RNA biology.

Sources and further reading

• Sidney Altman (Wikipedia)
• IRCM pays tribute to Dr. Sidney Altman, Nobel Prize winner ... (ircm.qc.ca)
• Tribute to Sidney Altman, PMC (pmc.ncbi.nlm.nih.gov)
• Sidney Altman (thecanadianencyclopedia.ca)
• Sidney Altman, pathbreaking scientist | Department of Chemistry (chem.yale.edu)

Checked by the Your Space Hamilton desk. Last updated 2026-11-02.