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美國100位歷史名人榜(68)James D. Watson

He codiscovered DNAs double helix, revealing the code of life to scientists and entrepreneurs alik

He codiscovered DNA’s double helix, revealing the code of life to scientists and entrepreneurs alike.
他和別人共同發現了DNA的雙螺旋結構,揭示了科學家和企業家身上具有相同的密碼。

Biography
James Dewey Watson (born April 6, 1928) is an American molecular biologist, best known as one of co-discoverers of the structure of DNA with Francis Crick, in 1953. Watson, Francis Crick, and Maurice Wilkins were awarded the 1962 Nobel Prize in Physiology or Medicine "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material". He studied at the University of Chicago and Indiana University and subsequently worked at the University of Cambridge's Cavendish Laboratory in England where he first met his future collaborator and personal friend Francis Crick.

In 1956, Watson became a junior member of Harvard University's Biological Laboratories until 1976, promoting research in molecular biology and from 1968 he served as director of Cold Spring Harbor Laboratory (CSHL) on Long Island, New York, greatly expanding its level of funding and research. At CSHL, he shifted his research emphasis to the study of cancer. In 1994, he became its president for ten years, and then subsequently he served as its chancellor until 2007, when he resigned, partially due to a controversy over comments he made about race and intelligence during an interview with a trusted friend that made it into the press.

Between 1988 and 1992, Watson was associated with the National Institutes of Health, helping to establish the Human Genome Project. Watson has written many science books, including the seminal textbook The Molecular Biology of the Gene (1965) and his bestselling book The Double Helix (1968) about the DNA structure discovery.

 

Early life and education
James Dewey Watson was born in Chicago, Ill., on April 6th, 1928, as the only son of James D. Watson, a businessman, and Jean Mitchell. His father was of Scottish descent (both Dewey and Watson being Scottish surnames).[3] His mother's father Lauchlin Mitchell, a tailor, was from Glasgow, Scotland, and her mother, Lizzie Gleason, was the child of Irish parents from Tipperary. Watson was fascinated with bird watching, a hobby he shared with his father. Watson appeared on Quiz Kids, a popular radio show that challenged precocious youngsters to answer questions. Thanks to the liberal policy of University president Robert Hutchins, he enrolled at the University of Chicago at the age of 15.

After reading Erwin Schrödinger's book What Is Life? in 1946, Watson changed his professional ambitions from the study of ornithology to genetics. Watson earned his B.S. degree in Zoology from the University of Chicago in 1947. In his autobiography, Avoid Boring People, Watson describes the University of Chicago as an idyllic academic institution where he was instilled with the capacity for critical thought and an ethical compulsion not to suffer fools who impeded his search for truth, in contrast to his description of later experiences. Watson attended Indiana University from 1947 to 1950 as a graduate student. He received his Ph.D. from IU in 1950.

Career in molecular biology
Watson was attracted to the work of Salvador Luria. Luria eventually shared a Nobel Prize for his work on the Luria-Delbrück experiment, which concerned the nature of genetic mutations. Luria was part of a distributed group of researchers who were making use of the viruses that infect bacteria, called bacteriophages. Luria and Max Delbrück were among the leaders of this new "Phage Group," an important movement of geneticists from experimental systems such as Drosophila towards microbial genetics. Early in 1948, Watson began his Ph.D. research in Luria's laboratory at Indiana University, and that spring he got to meet Delbrück in Luria's apartment and again that summer during Watson's first trip to the Cold Spring Harbor Laboratory (CSHL).

The Phage Group was the intellectual medium within which Watson became a working scientist. Importantly, the members of the Phage Group had a sense that they were on the path to discovering the physical nature of the gene. In 1949 Watson took a course with Felix Haurowitz that included the conventional view of that time: that proteins were genes and able to replicate themselves. The other major molecular component of chromosomes, DNA, was thought by many to be a "stupid tetranucleotide", serving only a structural role to support the proteins. However, even at this early time, Watson, under the influence of the Phage Group, was aware of the Avery-MacLeod-McCarty experiment, which suggested that DNA was the genetic molecule. Watson's research project involved using X-rays to inactivate bacterial viruses.He gained his Ph.D. in Zoology at Indiana University in 1950 (at age 22).

Watson then went to Copenhagen University in September 1950 for a year of postdoctoral research, first heading to the laboratory of biochemist Herman Kalckar. Kalckar was interested in the enzymatic synthesis of nucleic acids, and he wanted to use phages as an experimental system. Watson, however, wanted to explore the structure of DNA, and his interests did not coincide with Kalckar's. After working part of the year with Kalcker, Watson spent the remainder of his time in Copenhagen conducting experiments with microbial physiologist Ole Maaloe, then a member of the Phage Group.

The experiments, which Watson had learned of during the previous summer's Cold Spring Harbor phage conference, included the use of radioactive phosphate as a tracer to determine which molecular components of phage particles actually infect the target bacteria during viral infection. The intention was to determine whether protein or DNA was the genetic material, but upon consultation with Max Delbrück,they determined that their results were inconclusive and could not specifically identify the newly labeled molecules as DNA. Watson never developed a constructive interaction with Kalckar, but he did accompany Kalckar to a meeting in Italy where Watson saw Maurice Wilkins talk about his X-ray diffraction data for DNA.Watson was now certain that DNA had a definite molecular structure that could be elucidated.

In 1951, the chemist Linus Pauling in California published his model of the amino acid alpha helix, a result that grew out of Pauling's efforts in X-ray crystallography and molecular model building. Watson found out about Pauling's model quickly because it was communicated to him via Pauling's son, Peter Pauling, who had a copy of the manuscript. Watson claimed that such a model (with three central phosphate chains held together by hydrogen bonds) was easily recognized as incorrect because in an aqueous environment the phosphate groups would be ionized thus would not display hydrogen bonding and would repel each other. After obtaining some results from his phage and other experimental research conducted at Indiana University, Statens seruminstitute (Denmark), Cold Spring Harbor Laboratory, and the California Institute of Technology, Watson now had the desire to learn to perform X-ray diffraction experiments so that he could work to determine the structure of DNA. That summer, Luria met John Kendrew, and he arranged for a new postdoctoral research project for Watson in England.

 

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