Luria, Salvador Edward (Salvatore)
LURIA, SALVADOR EDWARD (SALVATORE)
(b. Turin, Italy, 13 August 1912; d. Lexington, Massachusetts, 6 February 1991),
virology, bacterial genetics, molecular biology, cancer research.
Luria was one of the central figures in the development of twentieth-century life sciences. His 1940s research on bacteriophage and its bacterial hosts laid the groundwork for the emergence of bacterial genetics and virology as independent disciplines. He shared the 1969 Nobel Prize in Physiology or Medicine with his longtime collaborators Max Delbrück and Alfred Hershey for “discoveries concerning virus replication and genetics and … the importance of your contributions to the biological and medical sciences.” Luria also played a role in the establishment of molecular biology, as his first graduate student was James D. Watson. His career trajectory from basic research on microorganisms to cancer research parallels the development of the life sciences in the postwar era. An immigrant to the United States, Luria was a passionate participant in American politics who publicly articulated his scientific and political ideals in the context of the Cold War.
Origins and Early Scientific Training . Salvatore Luria was born in the Northern Italian city of Turin, the second son of a lower-middle-class Jewish family. He was educated at Turin’s elite institutions, the Liceo Massimo d’Azeglio and the medical school of the University of Turin, at a time when the city was a seat of antifascist activity. At the Liceo, he studied philosophy and literature with Augusto Monti, a famous antifascist intellectual. In medical school, Luria worked for several years in the histology laboratory of the talented researcher Giuseppe Levi, who was also a committed antifascist. Although he was not politically active as a youth, these mentors impressed him with their dedication to democratic and rational ideals. Luria graduated from medical school with highest honors in 1935.
Luria was not interested in practicing medicine. During medical school, he became interested in the ways in which modern physics could be applied to problems in biology and genetics. After completing his required year of army service as a medical officer, he arranged to spend 1937–1938 studying with the physicist Enrico Fermi in Rome. During his year in Rome, he first encountered the work of physicist-turned-biologist Max Delbrück and began experimenting with bacteriophage, the viruses that attack bacteria. When Benito Mussolini passed a set of race laws that restricted the participation of Jews in public life in July 1938, Luria was prevented from pursuing a career in science in Italy. Luria took the opportunity to leave both Italy and medicine behind, and he moved to France to pursue virus research at the Institut Pasteur. He collaborated with Fernand Holweck and Eugène Wollman, and learned their statistical techniques for analyzing virus growth. When the Nazis invaded France in the spring of 1940, Luria fled again, this time to the United States via Portugal. He arrived in New York City on 12 September 1940.
Bacteriophage Research . As soon as he reached the United States, Luria began the process of becoming an American scientist. He secured funding from the Rockefeller Foundation and the Dazian Medical Foundation for Medical Research and was appointed to a temporary position in the Bacteriology Department at Columbia University. On his application for citizenship, Luria changed his first name from the Italian “Salvatore” to the Spanish spelling “Salvador” and added the English middle name “Edward.” He first met Delbrück in December 1940, and the two immediately began to collaborate.
Despite their geographic separation, Luria and Delbrück had an instant intellectual closeness. They arranged to spend the summer of 1941 at Cold Spring Harbor Laboratories, in New York, investigating the genetic and biochemical properties of bacteriophage and its host Escherichia coli. Their first joint publication described the curious way that two different strains of virus interfere with each other’s growth when both infect a colony of bacteria. They soon began to consider the implication of virus research for questions of resistance and evolutionary adaptation. Luria and Delbrück also collaborated with Thomas Anderson at the RCA Laboratories, taking some of the first electron micrograph images of bacteriophage.
During that summer at Cold Spring Harbor, Luria first met Milislav Demerec and Hermann Muller, both of whom were instrumental in helping him win a Guggenheim fellowship in 1942 and eventually to secure a permanent academic position. In January 1943, Luria moved to Bloomington, Indiana, to begin teaching in the Botany and Bacteriology Department at Indiana University. Luria and Delbrück returned to Cold Spring Harbor nearly every summer during the 1940s and 1950s to collaborate and to teach.
Luria flourished at Indiana professionally and personally. He formed close friendships with his colleagues including Leland McClung, Muller, and Tracy Sonneborn and began to train graduate students and postdoctoral researchers. His first advisee was James Dewey Watson, who soon became part of the larger community of phage researchers. In 1947 Luria invited his Italian medical school colleague Renato Dulbecco to work in his laboratory. Later, he was joined by Giuseppe Bertani, who worked on lysogeny and developed the standard culture for growing bacteria. Bertani referred to his “lysogeny broth” medium as “LB” in a 1951 paper, and the abbreviation soon became known as “Luria broth.” In 1945, Luria married Zella Hurwitz, the only female graduate student in the Department of Psychology. Their son Daniel was born in 1948.
Bacterial Genetics . A few weeks after he arrived in Bloomington, Luria got an idea for an experiment one Saturday night while watching a colleague play a slot machine at a faculty dance. Because he and Delbrück had first worked with bacterial resistance to phage, Luria had considered the problem of how that resistance arose. He considered two possible hypotheses: that the resistance was somehow triggered by the presence of bacteriophage, or that some of the bacteria were already resistant as a result of random genetic mutations. However, it was unclear how to test these possibilities experimentally.
As he teased his friend about gambling, Luria realized that mutations in bacteria could be considered analogous to jackpots. He saw that jackpots in an unprogrammed slot machine are a series of random events that could be described with a Poisson distribution of rare independent events. Luria hypothesized that if bacterial resistance to bacteriophage was the result of spontaneous random mutations, then it would appear in a random distribution of “jackpots” in a series of cultures. Some cultures could have many resistant colonies while others could have none. If, on the other hand, resistance was acquired as a result of contact with phage, resistant colonies would be evenly distributed across all cultures. In either case, the average number of resistant colonies across all cultures could be the same, but the distribution would indicate whether the cause was spontaneous or not.
Luria ran the experiment with α, a virulent strain of phage, and as he anticipated, he found several jackpots randomly distributed among the plates. Luria was fortunate to have chosen virulent phage. If he had used a temperate strain, he would have seen that the presence of phage did induce resistance, and he would have concluded that it was acquired rather than hereditary. Excited by his results, Luria consulted with Delbrück, who noted that the experiment also provided a way to determine mutation rates with greater precision than had been possible before.
This experiment, known as the fluctuation test, was published in Genetics in 1943. The implications of Luria and Delbrück’s work went far beyond the handful of researchers interested in phage. As Luria and others have pointed out, the 1943 paper dealt a blow to the neo-Lamarckian view that viruses somehow induced mutations in bacteria. In a 1947 review, Luria noted that bacteriology had been “one of the last strongholds of Lamarckism,” because of the difficulty in providing direct evidence for the existence of both Mendelian traits and the characteristic Darwinian criteria of random change (p. 1). The fluctuation test marked the beginning of Luria’s appreciation for the evolutionary implications of his genetics research, and his interest in larger biological questions was evident in his publications through the 1950s. Gunther Stent’s classic textbook Molecular Genetics equates this publication with Gregor Mendel’s 1865 paper on “Versuche über Pflanzenhybriden” (Experiments on plant hybrids), and historian Thomas Brock identifies it as the founding document of modern bacterial genetics.
Luria had a small role in the Western scientific campaign to discredit Trofim Lysenko’s Lamarckian genetics program in the Soviet Union. In 1946, Luria drafted a letter to the British biologist J. B. S. (John Burdon Sanderson) Haldane asking him to publish a critique of Lysenko’s book Heredity and Its Variability. Muller, Theodosius Dobzhansky, Leslie Dunn, Curt Stern, and Luria signed the letter, which enraged Haldane, a committed Communist, so much that he not only refused to write the review, but returned the original letter to Muller. Later in the 1940s and early 1950s, Luria served as a member of the Genetics Society of America’s Committee to Aid Geneticists Abroad and he ran unsuccessfully for a spot on the society’s Committee to Combat Anti-genetic Propaganda.
Luria’s early experiments with bacteriophage earned him recognition from the biological community and helped establish viruses as useful research organisms. In 1945 he won a grant from the American Cancer Society’s Committee on Growth, which was renewed for over twenty years. Luria delivered the first Slotin Memorial Lecture in 1948 and gave the 1950 Jesup Lectures at Columbia University on “The Reproduction of Viruses.” Several top biology and bacteriology departments tried to recruit Luria and in 1950 he accepted an offer from the University of Illinois at Urbana-Champaign to join their Department of Bacteriology.
Restriction-Modification . Luria continued his innovative virus research in Illinois. His second key finding—host-induced modifications of viruses—was the result of a laboratory accident rather than a planned experiment. In the spring of 1952, Luria and his graduate student Mary Human reported a “novel situation” that they had observed. A test tube full of phage-sensitive E. coli culture broke, so Luria substituted a different bacterium, Shigella dysenteriae, and observed a surprising phenomenon. After exposure to Shigella, the viruses would not grow in E. coli. Some bacterial mutants had temporarily modified their viral invaders so that they could not reproduce in certain bacterial hosts.
In a series of experiments with different phages and a range of E. coli and Shigella hosts, some of the phages seemed to disappear, only to reappear when cultured with different bacteria. Luria and Human observed that one generation later, the phages once again reproduced in the original hosts. They concluded that whatever had caused the modification in the viruses was not a mutation, which would have caused permanent genetic change, or even evidence of the “peculiar plasticity of virus heredity” (Luria, 1953a, p. 237). Rather, they had found a new type of genetic variation, which they labeled “host-induced” (Luria and Human, 1952, p. 557) and later became known as the restriction-modification phenomenon.
For several years, restriction-modification was a laboratory curiosity for virologists and bacterial geneticists. In the 1960s, however, other researchers discovered that the temporary changes were the result of bacterial restriction enzymes that degraded viral DNA as a defense mechanism. Restriction enzymes, which recognize and target short strands of DNA, were key for the development of recombinant DNA technology in the late 1960s and early 1970s, which in turn is the basis for genetic engineering and other types of genetic manipulation. Luria later acknowledged that his role in the history of recombinant DNA technology was “accidental” and “serendipitous” (Luria, 1983, p. 57); this episode provides further evidence of his far-reaching influence on modern biology.
Virology . The 1950s were a critical decade in the history of virology. Luria was a strong force in the establishment of virology as an independent discipline and he published several important pieces on the utility of viruses as a fundamental biological unit. In “Bacteriophage: An Essay on Virus Reproduction” published in May 1950 in Science, he made a clear argument for virology as the key discipline that would help biologists reach their “ultimate goal, the identification of the elementary ‘replicating units’ of biological material and the clarification of their mode of reproduction” (p. 511). This essay, also published as a core reading for a California Institute of Technology conference on viruses in March 1950, gives an operational definition of viruses that emphasizes their research functions rather than their disease-causing features. A virus is “an exogenous submicroscopic unit capable of
multiplication only inside specific living cells” (p. 507). It describes the relationship between viruses and hosts as “parasitism at the genetic level,” and argues that understanding the biochemical and genetic features of that relationship would lead directly to a detailed description of all biological replication (pp. 510–511).
Nearly three years later, in April 1953, Luria’s student James Watson and his Cambridge colleague Francis Crick announced that they had discovered the double helical structure of DNA, the molecule that constitutes genetic material. Watson, Stent, and John Cairns bound the early history of molecular biology with bacteriophage in their festschrift for Delbrück’s sixtieth birthday, the classic Phage and the Origins of Molecular Biology. Although historians have demonstrated that many disciplinary strands came together to form molecular biology, the bacteriophage experiments performed by Seymour Cohen, Alfred Hershey, and Martha Chase provided critical evidence that DNA is the physical location of genetic material.
General Virology . The year 1953 was a turning point in the independent disciplinary history of virology as well. That year, Luria published General Virology, the first comprehensive textbook in the field. The text emerged from Luria’s teaching experience in Indiana. In the preface, he recalled how in 1946 he began planning a new course in virology, one that was not “a watered-down course in virus diseases,” but rather “a new type of course, in which virology would be presented as a biological science, like botany, zoology, or general bacteriology” (p. ix). His approach for the course and for the textbook accepted the ambiguities inherent in nonmedical virus research, and made it “a central concept, that of the dual nature of viruses as inert particles on the one hand, and as operating constituents of functional cells on the other hand” (p. x). Physics, chemistry, biochemistry, and cell physiology were thus integrated into the study of virus properties and behavior, while pathology was relegated to a supporting role.
In the textbook, Luria argued that virology should be considered an integrative and interpretive science, rather than a taxonomic one. By defining virology as the science concerned with the genetic and chemical properties and functions of viruses, he emphasized methodology over taxonomy. He was unequivocal about the relevance of virus research to fundamental biological questions. Some biologists felt that viruses should not be considered living, since they could not reproduce independently. However, Luria felt that the genetic dependence of viruses “makes them invaluable to the biologist, whom they present with the unique opportunity of observing in isolation the active determinants of biological specificity, which are truly the stuff of which all life is made” (p. 363). Luria took pains to establish virology as a basic science, but from the very start, his research had implications for the applied field of cancer research.
Viruses and Cancer . In 1959 the American Cancer Society organized a three-day meeting to discuss “The Possible Role of Viruses in Cancer” and to assess the state of the field. The conference brought together a diverse group of the most prominent researchers in the areas of animal, plant, and bacterial viruses, including Peyton Rous, Wendell Stanley, Renato Dulbecco, François Jacob, and André Lwoff. Luria was invited to give the keynote orienting address for the meeting and the papers were published in Cancer Research in 1960.
In “Viruses, Cancer Cells, and the Genetic Concept of Virus Infection,” Luria reviewed basic virology findings that were relevant to cellular function, which is a crucial element in the understanding of cancer as the result of abnormal cell growth and control. He noted that viruses could be implicated in the development of cancer either as the cause of somatic mutations or as a direct infection of a tumor-causing agent. In both cases, viruses could be seen as causing a type of cellular mutation since the “entry of the viral genome is a genetic change” (p. 679) and viral tumors thus would be examples of “infective heredity at the cellular level” (p. 680). While this view of the relationship between cancer and viruses was not universally accepted, it was a strong approach taken by many researchers for the next several decades.
1950s: Early Political Activity . Because of his left-leaning political affiliations, Luria attracted the attention of the Federal Bureau of Investigation (FBI) in 1950. A two-year investigation yielded no evidence of Communist or other subversive activity, but Luria was nevertheless denied a passport in 1952. He was scheduled to give a lecture at the Society for General Microbiology meeting in Oxford, England, and to visit his mother in Italy, but he was told by Ruth Shipley, chief of the passport division of the State Department, that his “proposed travel would not be in the best interest of the United States” (letter from Shipley to S.E.L., 25 January 1952, State Department correspondence folder, Luria papers, American Philosophical Society). Despite appeals by Luria and the president of the University of Illinois, Luria was not granted permission to leave the United States. James Watson reported on the latest phage research in Luria’s stead, and Luria was not granted a passport until 1959.
This treatment did not deter him, however, and Luria increased his political activities during the 1950s. He helped organize protests against Illinois state laws requiring university professors and other employees to sign loyalty oaths, and was active in local labor and desegregation campaigns. In his capacity as a vice president of the American Association for the Advancement of Science, he participated in a lively debate about the appropriateness of holding a national scientific meeting in racially segregated Atlanta. Luria was one of the first signers of Linus Pauling’s 1957 “Appeal by American Scientists to the Government and Peoples of the World” to ban nuclear weapons.
Move to Boston . In 1959 the Luria family moved to Boston. Because rules against nepotism barred two members of the same family from teaching at the University of Illinois, Zella Luria could not find work as a psychology professor in Urbana. She was offered a position at Tufts University and Salvador accepted an invitation from the Massachusetts Institute of Technology (MIT) to join their Department of Biology. With the exception of the time he spent at the Pasteur Institute in 1963 as a Guggenheim Fellow, Luria remained at MIT for the rest of his career.
At MIT, Luria was instrumental in transforming their Department of Biology into a world-class research community. Along with fellow faculty members Boris Magasanik, Alexander Rich, and Irwin Sizer, he recruited top researchers and graduate students, including David Baltimore. He helped shift the department’s pedagogical focus toward genetics and microbiology and in the process increased undergraduate enrollment significantly. Luria was elected to the National Academy of Sciences in 1960. In 1966, he was named the first William Thompson Sedgwick Professor of Biology and in 1970 he became an institute professor. Luria’s status as an authority on viruses and cancer helped MIT win one of the first federal grants for basic cancer research as part of the “war on cancer.” Luria served as the director of MIT’s Center for Cancer Research from 1972 until he retired in 1985.
Protesting the Vietnam War . The height of Luria’s political involvement came in the 1960s and 1970s. He was one of the founding members of the Boston Area Faculty Group on Public Issues, a cohort of academics who sponsored advertisements and wrote editorials on political issues. Their main focus was on protesting the Vietnam War in a series of advertisements in the New York Times and other national publications. The most dramatic advertisement appeared in January 1967. Surrounding the words “Mr. President, Stop the Bombing” were the names of more than two thousand academics from around the United States.
Luria’s leadership role in the scientific community gave him the opportunity to mobilize biologists against the Vietnam War. As the president of the American Society for Microbiology in 1968, he announced that the society would terminate its advisory relationship with the U.S. Army’s Biological Laboratory at Fort Detrick, Maryland. In a widely publicized address on “The Microbiolo-gist and His Times,” Luria articulated a vision of “a society in which science will flourish, both as a liberating intellectual activity and as the source of a beneficial technology” (1968, p. 403).
Public Figure . Luria’s public roles converged in one dramatic weekend in October 1969. He helped organize the Vietnam War Moratorium in Boston on 15 October. The next day, his Nobel Prize was announced, and Luria declared that he would donate part of his prize money to the peace movement. On 20 October, Luria again made headlines when his name was found on a list of scientists who had been blacklisted from serving on advisory committees at the National Institutes of Health, presumably because of their political views.
Late in his career, Luria had many opportunities to argue for the value of science in a democratic society. He testified before Senate and Congressional committees on science policy, and was one of the first fellows of the Salk Institute in La Jolla, California. He wrote articles, textbooks, curricula, and a popular science book. In Life: The Unfinished Experiment (1973), he explained evolution, genetics, and molecular biology to a general audience while critiquing sociobiology and other examples of biological determinism. This book was a critical success and won the National Book Award in 1974. Luria continued to publish essays and op-eds on scientific and political issues until his death from cancer on 6 February 1991.
A complete bibliography is available in Luria’s papers, deposited at the American Philosophical Society Library in Philadelphia. A list of many of his scientific publications since 1955 can be retrieved through the Web of Science database. Other archival sources include the collections at the American Society for Microbiology, the Cold Spring Harbor Laboratory, Indiana University, the Massachusetts Institute of Technology, the Rockefeller Archive Center, and the University of Illinois, Urbana-Champaign. Luria’s FBI files were obtained by this author through a Freedom of Information Act request in 1999.
WORKS BY LURIA
With Thomas F. Anderson. “The Identification and Characterization of Bacteriophages with the Electron Microscope.” Proceedings of the National Academy of Sciences of the United States of America 28 (1942): 127–130.
With Max Delbrück. “Interference between Bacterial Viruses: I. Interference between Two Bacterial Viruses Acting upon the Same Host, and the Mechanism of Virus Growth.” Archives of Biochemistry 1 (1942): 111–141.
With Max Delbrück. “Interference between Inactivated Bacterial Virus and Active Virus of the Same Strain and of a Different Strain.” Archives of Biochemistry 1 (1942): 207–218.
With Max Delbrück. “Mutations of Bacteria from Virus Sensitivity to Virus Resistance.” Genetics 28 (1943): 491–511.
With Max Delbrück and Thomas F. Anderson. “Electron Microscope Studies of Bacterial Viruses.” Journal of Bacteriology 46 (1943): 57–76.
“Recent Advances in Bacterial Genetics.” Bacteriological Reviews 11 (1947): 1–40.
With Renato Dulbecco. “Genetic Recombinations Leading to Production of Active Bacteriophage from Ultraviolet Inactivated Bacteriophage Particles.” Genetics 34 (1949): 93–125.
“Bacteriophage: An Essay on Virus Reproduction.” Science 111 (12 May 1950): 507–511. Reprinted in Viruses 1950, edited by Max Delbrück. Pasadena: Division of Biology of the California Institute of Technology, 1950.
With Mary L. Human. “A Nonhereditary, Host-Induced Variation of Bacterial Viruses.” Journal of Bacteriology 64 (1952): 557–569.
General Virology. New York: John Wiley and Sons, 1953a. “Host-Induced Modifications of Viruses.” In Viruses. Cold Spring Harbor Symposia on Quantitative Biology 18. Cold Spring Harbor, NY: Cold Spring Harbor Press, 1953b.
“Viruses, Cancer Cells, and the Genetic Concept of Virus Infection.” Cancer Research 20 (June 1960): 677–688.
“Mutations of Bacteria and of Bacteriophage.” In Phage and the Origins of Molecular Biology, edited by John Cairns, Gunther Stent, and James D. Watson. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press, 1966. Revised and expanded ed., 1992.
With James E. Darnell Jr. General Virology. 2nd ed. New York: John Wiley and Sons, 1967.
“The Microbiologist and His Times.” Bacteriological Reviews 32 (December 1968): 401–403.
Life: The Unfinished Experiment. New York: Charles Scribner’s Sons, 1973.
36 Lectures in Biology. Cambridge, MA: MIT Press, 1975.
“Phage; Colicins and Macroregulatory Phenomena.” In Nobel Lectures in Molecular Biology, 1933–1975, edited by David Baltimore. New York: Elsevier, 1977.
With James E. Darnell Jr., David Baltimore, and Allan Campbell. General Virology. 3rd ed. New York: John Wiley and Sons, 1978.
With Stephen Jay Gould and Sam Singer. A View of Life. Menlo Park, CA: Benjamin/Cummings, 1981.
A Slot Machine, a Broken Test Tube: An Autobiography. New York: Harper and Row, 1984.
Abir-Am, Pnina G. “Entre mémoire collective et histoire en biologie moléculaire: les premiers rites commémoratifs pour les groupes fondateurs.” In La mise en mémoire de la science: Pour une ethnographie historique des rites commémoratifs, edited by Pnina G. Abir-Am. Amsterdam: Overseas Publishers Association, 1998.
Bertani, Giuseppe. “Lysogeny at Mid-Twentieth Century: P1, P2, and Other Experimental Systems.” Journal of Bacteriology 186 (2004): 595–600.
Brock, Thomas D. The Emergence of Bacterial Genetics. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press, 1990.
Cairns, John, Gunther Stent, and James D. Watson, eds. Phage and the Origins of Molecular Biology. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press, 1966. Revised and expanded ed., 1992. This volume, published in honor of Max Delbrück’s sixtieth birthday, was the first attempt by molecular biologists to write their own history.
Fischer, Ernst Peter, and Carol Lipson. Thinking about Science: Max Delbrück and the Origins of Molecular Biology. New York: W. W. Norton, 1988.
Judson, Horace Freeland. The Eighth Day of Creation: Makers of the Revolution in Biology. New York: Simon & Schuster, 1979. One of the standard historical accounts of the emergence of molecular biology, based on extensive interviews with the participants.
Kay, Lily E. “Conceptual Models and Analytical Tools: The Biology of Physicist Max Delbruck.” Journal of the History of Biology 18, no. 2 (Summer 1985): 207–247.
Krementsov, Nikolai. “A ‘Second Front’ in Soviet Genetics: The International Dimension of the Lysenko Controversy, 1944–47.” Journal of the History of Biology 29 (1996): 229–250.
Lysenko, Trofim Denisovich. Heredity and Its Variability. Translated from the Russian by Theodosius Dobzhansky. New York: King’s Crown Press, 1945.
Mendel, Gregor. “Versuche über Pflanzenhybriden.” Verhandlungen des Naturforschenden Vereins in Brünn 4 (1866): 3–57. Read at 1865 meeting.
Morange, Michel. A History of Molecular Biology. Cambridge, MA: Harvard University Press, 1998.
“Nobel Prize in Physiology or Medicine, 1969.” Nobel Prize Web site. Available from http://nobelprize.org/nobel_prizes/medicine/.
Olby, Robert. The Path to the Double Helix: The Discovery of DNA. Seattle: University of Washington Press, 1974. 2nd ed., 1994. Another standard historical account, focusing more on the technological and experimental roots of the discovery of DNA.
Rasmussen, Nicolas. Picture Control: The Electron Microscope and the Transformation of Biology in America, 1940–1960. Stanford, CA: Stanford University Press, 1997.
Selya, Rena. “Salvador Luria’s Unfinished Experiment: The Public Life of a Biologist in Cold War America.” PhD diss., Harvard University, 2002.
Stent, Gunther S. Molecular Genetics: An Introductory Narrative. San Francisco: W. H. Freeman, 1970.
Summers, William C. “How Bacteriophage Came to Be Used by the Phage Group.” Journal of the History of Biology 26 (1993): 255–267.
Watson, James D. “Growing up in the Phage Group.” In Phage and the Origins of Molecular Biology, edited by John Cairns, Gunther Stent, and James D. Watson. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press, 1966. Revised and expanded ed., 1992.
———. The Double Helix: A Personal Account of the Discovery of the Structure of DNA. Norton Critical Edition, edited by Gunther Stent. New York: W. W. Norton, 1980. James Watson was Luria’s first graduate student. These two works reflect Watson’s intense interest in shaping how the history of molecular biology is written and presented to the public.
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Luria, Salvador Edward
Salvador Edward Luria, 1912–1991, American physician, b. Turin, Italy, M.D., Univ. of Turin, 1935. He conducted research and taught at the Institute of Radium in Paris (1938–40), Columbia (1940–42), Indiana Univ. (1943–50), and the Univ. of Illinois (1950–59) before joining the faculty at the Massachusetts Institute of Technology in 1959. In 1969 Luria, Max Delbrück, and Alfred Hershey were awarded the Nobel Prize in physiology or medicine for uncovering new information about the replication mechanism and genetic structure of viruses. Beginning in 1940, the researchers, working in parallel, became interested in using bacteriophages (viruses that infect bacteria) to study such fundamental life processes as self-replication and mutation. Luria conducted experiments that supported Delbrück's finding that radiation-induced genetic damage in bacteriophages could be repaired by gene exchange. The collective work of these three scientists contributed substantially to the discipline of virology and to the progress of molecular biology.
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