- Born:
- May 7, 1939, Montreal, Quebec, Canada
- Died:
- April 5, 2022, Rockleigh, New Jersey, U.S. (aged 82)
- Awards And Honors:
- Nobel Prize (1989)
- Subjects Of Study:
- RNA
- catalysis
- ribonucleoprotein
Sidney Altman
-
Who was Sidney Altman?
Sidney Altman (1939–2022) was a Canadian-American molecular biologist celebrated for his groundbreaking work on the catalytic properties of RNA. With Thomas R. Cech, he was awarded the 1989 Nobel Prize in Chemistry for his revolutionary discovery that RNA, traditionally seen as a passive carrier of genetic codes, could also possess active enzymatic functions.
Altman's research at Yale University, and earlier at the Medical Research Council Laboratory of Molecular Biology, led to the identification of ribonuclease P (RNase P), an enzyme containing an RNA segment that serves as the enzyme's catalytic portion. His and Cech's findings challenged the long-held belief that enzymatic activity was exclusive to protein molecules, opening new avenues in scientific research, biotechnology, and theories about the origins of life on Earth.
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What was Sidney Altman best known for in science?
Sidney Altman was a Canadian-American molecular biologist who received the 1989 Nobel Prize in Chemistry with Thomas R. Cech for their groundbreaking discovery that RNA can act as an enzyme. Before Altman and Cech's work, it was believed that only proteins could have enzymatic activity, which is the ability to trigger and accelerate chemical reactions within cells.
Altman's Nobel Prize-winning research involved the discovery that RNA, traditionally known as a passive carrier of genetic codes, can also perform active enzymatic functions. He discovered that the RNA segment within the enzyme ribonuclease P (RNase P) serves as the catalytic portion of the enzyme. This discovery revolutionized scientific understanding of cell function, opened new avenues for research and biotechnology, and led to hypotheses about the emergence of RNA and the origins of life on Earth.
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What is RNA and why did Sidney Altman study it?
RNA, or ribonucleic acid, is a high-molecular-weight compound that facilitates protein synthesis in cells and, in some viruses, replaces DNA as the genetic code carrier. RNA consists of ribose nucleotides attached by phosphodiester bonds, forming strands of varying lengths.
Sidney Altman studied RNA and discovered that RNA has catalytic properties. He, along with Thomas R. Cech, jointly received the 1989 Nobel Prize in Chemistry for their work concerning the catalytic properties of RNA, now known as ribozymes. Altman's work revealed that RNA, previously considered a passive carrier of genetic codes, could also perform active enzymatic functions.
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What major discovery did Sidney Altman make about RNA?
Sidney Altman, along with Thomas Cech, won the 1989 Nobel Prize in Chemistry for discovering the catalytic properties of RNA (ribonucleic acid). Their revolutionary discovery challenged the belief that enzymatic activity was exclusive to protein molecules. Altman and Cech found that RNA, traditionally seen as a passive carrier of genetic codes, could also perform active enzymatic functions. Specifically, Altman showed that the RNA component of ribonuclease P (RNase P) could cleave precursor tRNA to generate mature tRNA. These findings opened new avenues in scientific research and biotechnology and led to new hypotheses about the origins of life on Earth.
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How did Sidney Altman's discovery change the way scientists understand genetics?
Sidney Altman's groundbreaking discovery, alongside Thomas Cech, that RNA possesses catalytic properties revolutionized the understanding of genetics. This overturned the long-held belief that enzymatic activity was exclusive to protein molecules.
Altman's work on ribonuclease P (RNase P) revealed that the RNA component within this enzyme was the active, catalytic portion. This discovery opened new fields in scientific research and biotechnology, prompting a rethinking of cellular functions and new hypotheses about the origins of life on Earth. The RNA world hypothesis suggests that RNA may have been the primary molecule for both catalysis and genetic information storage early in evolution.
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What awards or honors did Sidney Altman receive for his contributions to science?
Sidney Altman, a Canadian-American molecular biologist, received the 1989 Nobel Prize in Chemistry with Thomas R. Cech for their groundbreaking discoveries concerning the catalytic properties of RNA. Their revolutionary discovery challenged the traditional belief that enzymatic activity was exclusive to protein molecules. Altman's work opened new avenues of scientific research and biotechnology, prompting a reevaluation of how cells function and new hypotheses about the origins of life on Earth.
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Sidney Altman (born May 7, 1939, Montreal, Quebec, Canada—died April 5, 2022, Rockleigh, New Jersey, U.S.) was a Canadian American molecular biologist who, with Thomas R. Cech, received the 1989 Nobel Prize for Chemistry for their discoveries concerning the catalytic properties of RNA, or ribonucleic acid.
Altman received a B.S. in physics in 1960 from the Massachusetts Institute of Technology. After a brief period as a graduate student in the physics department at Columbia University, Altman changed his course of study and enrolled in the graduate program in biophysics at the University of Colorado. There he studied chemical compounds called acridines, focusing primarily on how these compounds affect the replication of bacteriophages (viruses that infect bacteria). Altman received a Ph.D. in biophysics in 1967. He then was awarded a fellowship to work at Harvard University, where he conducted research on bacteriophages under the guidance of American molecular biologist Matthew Stanley Meselson. In 1969 Altman became a researcher at the Medical Research Council Laboratory of Molecular Biology in Cambridge, Eng. There he worked with British biophysicist Francis Crick and South African biologist Sydney Brenner and embarked on the research that would later lead to his Nobel Prize-winning discoveries. Altman joined the biology faculty at Yale University in 1971, where he became a full professor in 1980 and was the department chairman from 1983 to 1985. Altman also served as dean of the undergraduate Yale College from 1985 to 1989. He took U.S. citizenship in 1984 but concurrently retained his Canadian citizenship.
Altman’s initial investigations into RNA concerned a small molecule called transfer RNA (tRNA), which carries amino acids to organelles called ribosomes, where the amino acids are linked into proteins. He isolated and characterized a precursor molecule in the biochemical pathway leading to the synthesis of tRNA and subsequently identified an enzyme called ribonuclease P (RNase P), which cleaved a specific bond within the precursor molecule. This enzymatic cleavage enabled the tRNA synthetic pathway to advance to the next step. During purification of RNase P, Altman discovered that there was an RNA segment within the enzyme and that this segment served as the active, or catalytic, portion of the enzyme.
Altman was working independently of Cech when both discovered the catalytic properties of RNA. The old belief was that enzymatic activity—the triggering and acceleration of vital chemical reactions within living cells—was the exclusive domain of protein molecules. Altman’s and Cech’s revolutionary discovery was that RNA, traditionally thought to be simply a passive carrier of genetic codes between different parts of the living cell, could also take on active enzymatic functions. This knowledge opened up new fields of scientific research and biotechnology and caused scientists to rethink old theories of how cells function. It also led to new hypotheses about the history of the emergence of RNA on Earth and the possibility that RNA was the molecule that gave rise to Earth’s first life forms.