Salvador Luria

Salvador Edward Luria (Turin, Italy, August 13, 1912 – Lexington, Massachusetts, February 6, 1991) was an Italian microbiologist.
He won the 1969 Nobel Prize in Physiology or Medicine for his pioneering work with Max Delbrück and Alfred Hershey on phages in molecular biology.
Biography.
Luria was born Salvatore Edoardo Luria in Turin, Italy to an influential Italian Sephardic Jewish family. He attended the medical school at the University of Turin. There, he met two other future Nobel laureates: Rita Levi-Montalcini and Renato Dulbecco.
In Rome, he was introduced to Max Delbrück's theories on the gene as a molecule and began to formulate methods for testing genetic theory with bacteriophages, which are 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 Marseilles where he received an immigration visa to the United States.
Phage research.
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 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 that inheritance in bacteria follows Darwinian rather than Lamarckian principles and that mutant genes occurring randomly can still give 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.
From 1943 to 1950, he worked at Indiana University, Bloomington. 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 at Urbana-Champaign. While investigating how a culture of "E. coli" was able to stop the production of phages, Luria discovered that specific bacterial strains produce enzymes that cut DNA at certain sequences. These enzymes became known as restriction enzymes and developed into one of the main molecular tools in molecular biology.