Early life Luria was born Salvatore Luria in
Turin, Italy to an influential Italian
Sephardi Jewish family. His parents were Davide and Ester (Sacerdote) Luria. He attended the medical school at the
University of Turin studying with
Giuseppe Levi. There, he met two other future
Nobel laureates:
Rita Levi-Montalcini and
Renato Dulbecco. He obtained his M. D.
summa cum laude in 1935. From 1936 to 1937, Luria served his required time in the Italian army as a medical officer. He then took classes in
radiology at the
University of Rome. Here, he was introduced to
Max Delbrück's theories on the
gene as a molecule and began to formulate methods for testing genetic theory with the
bacteriophages,
viruses that infect
bacteria. In 1938, he received a fellowship to study in the United States, where he intended to work with Delbrück. Soon after Luria received the award,
Benito Mussolini's
fascist regime banned Jews from academic research fellowships. Without funding sources for work in the U.S. or Italy, Luria left his home country for Paris, France in 1938. As the
Nazi German armies invaded France in 1940, Luria fled on bicycle to
Marseille where he received an immigration
visa to the United States.
Phage research at the 1953 Cold Spring Harbor Symposium. In the background are
Aaron Novick, Bruce Stocker, Haig Papazian and Geraldine Lindegren. Luria arrived in New York City on September 12, 1940, and soon changed his first and middle names. With the help of physicist
Enrico Fermi, whom he knew from his time at the University of Rome, Luria received a
Rockefeller Foundation fellowship at
Columbia University. He soon met Delbrück and Hershey, and they collaborated on experiments at
Cold Spring Harbor Laboratory and in Delbrück's lab at
Vanderbilt University. His famous experiment with Delbrück in 1943, known as the
Luria–Delbrück experiment, demonstrated statistically that inheritance in bacteria must follow
Darwinian rather than
Lamarckian principles and that
mutant bacteria occurring randomly can still bestow viral resistance without the virus being present. The idea that natural selection affects bacteria has profound consequences, for example, it explains how bacteria develop
antibiotic resistance. Luria and Latarjet in 1947 published a quantitative analysis on the effect of
ultraviolet irradiation on
bacteriophage multiplication during intracellular growth. During the early course of infection they found an increase in bacteriophage resistance to ultraviolet irradiation and then later a decrease. At the time this pattern, known as the Luria-Laterjet effect, was published little was known about the central role of
DNA in biology. Later work established that multiple specific
DNA repair pathways, encoded by the infecting bacteriophage, contribute to the increase in UV resistance early in infection. From 1943 to 1950, he worked at
Indiana University. His first graduate student was
James D. Watson, who went on to discover the structure of
DNA with
Francis Crick. In January 1947, Luria became a
naturalized citizen of the United States. In 1950, Luria moved to the
University of Illinois Urbana–Champaign. In the early 1950s, Luria and
Giuseppe Bertani discovered the phenomenon of
host-controlled restriction and modification of a bacterial virus: a culture of
E. coli can significantly reduce the production of phages grown in other strains; however, once the phage become established in that strain, they also become restricted in their ability to grow in other strains. It was later discovered by other researchers that bacteria produce
enzymes that cut viral DNA at particular sequences but not the bacteria's own DNA, which is protected by
methylation. These enzymes became known as
restriction enzymes and developed into one of the main molecular tools in
molecular biology. Luria won the
Nobel Prize in Physiology or Medicine in 1969, with
Max Delbrück and
Alfred Hershey, for their discoveries on the replication mechanism and the genetic structure of viruses.
Later work In 1959, he became chair of Microbiology at the
Massachusetts Institute of Technology (MIT). At MIT, he switched his research focus from phages to
cell membranes and
bacteriocins. While on sabbatical in 1963 to study at the
Institut Pasteur in Paris, he found that bacteriocins impair the function of cell membranes. Returning to MIT, his lab discovered that bacteriocins achieve this impairment by forming holes in the cell membrane, allowing
ions to flow through and destroy the
electrochemical gradient of cells. In 1972, he became chair of The
Center for Cancer Research at MIT. The department he established included future Nobel Prize winners
David Baltimore,
Susumu Tonegawa,
Phillip Allen Sharp and
H. Robert Horvitz. In addition to the Nobel Prize, Luria received a number of awards and recognitions. He was elected to the
American Academy of Arts and Sciences in 1959. He was named a member of the
National Academy of Sciences in 1960. In 1964, he was elected to the
American Philosophical Society. From 1968 to 1969, he served as president of the
American Society for Microbiology. In 1969, he was awarded the
Louisa Gross Horwitz Prize from
Columbia University together with
Max Delbrück, co-winner with Luria of the Nobel Prize in Physiology or Medicine in 1969. In the U.S. he won the 1974
National Book Award in Science for his
popular science book
Life: the Unfinished Experiment and received the
National Medal of Science in 1991.
Political activism Throughout his career, Luria was an outspoken political advocate. He joined with
Linus Pauling in 1957 to protest against nuclear weapon testing. Luria was an opponent of the
Vietnam War and a supporter of
organized labor. In the 1970s, he was involved in debates over
genetic engineering, advocating a compromise position of moderate oversight and regulation rather than the extremes of a complete ban or full scientific freedom. Due to his political involvement, he was
blacklisted from receiving funding from the
National Institutes of Health for a short time in 1969.
Noam Chomsky describes him as a friend, and writes that Luria attempted to influence Jewish American writer
Elie Wiesel's public stance on Israel.
Death Luria died in
Lexington, Massachusetts of a heart attack on 6 February 1991 at the age of 78. == Books ==