Joshua Lederberg

Nobel Prize winner for discovery of genetic recombination in bacteria. Born on May 23, 1925, in Montclair, NJ, USA, he died on Feb 2, 2008, in New York, NY, USA, of pneumonia. When Joshua Lederberg began medical school at Columbia in 1944, biologists were buzzing with news of Oswald Avery's discovery that DNA was the genetic material. Lederberg was similarly captivated, he would later recall in the National Library of Medicine's Profiles in Science series, so while in medical school, he continued work he had begun earlier with biochemist Francis Ryan. Lederberg's first experiments, in Neurospora, a bread mould, were designed to find evidence that DNA exchange could transform the characteristics of bacterial strains. They failed, because of a particular characteristic of the species, which can revert to wild-type in the absence of essential aminoacids. But it did allow Lederberg to publish his first paper on a technique for picking out strains that could revert. And it encouraged him to take a leave of absence from medical school, in 1946, to work with Yale's Edward Tatum, who was studying genetics of bacteria. Escherichia coli would become the key to Lederberg's success. Lederberg and Tatum's research found that certain strains of E coli could reproduce sexually. The finding overturned biological dogma, and set the stage for work on “genetic recombination and the organisation of the genetic material of bacteria” for which Lederberg would share the 1958 Nobel Prize in Physiology or Medicine. That work would also make genetic engineering possible from the 1970s. Lederberg never finished medical school. He was only 22 years old when he accepted a position at the University of Wisconsin at Madison, in 1947, soon after Yale granted him a PhD in biochemistry. He had married microbiologist Esther Zimmer by that time. The two developed the technique of replica plating, among other work on viral transduction. After founding the University of Wisconsin's department of medical genetics, in 1957, Lederberg accepted a position at Stanford University, where he was the first chair of the medical school's department of genetics. He had accepted the offer days before winning the 1958 Nobel Prize. He was known for sitting quietly through presentations. Larry Kedes recalled his first encounter with Lederberg as a Stanford faculty member: “Josh entered carrying a stack of journals and a paper sack lunch. Josh appeared to be paying little attention to the presentation; he rummaged in his sack with gusto for lunch items and read the journals intently,” Kedes wrote in a comment to The Scientist magazine. “But about 20 minutes into the talk he interrupted with a devastating barrage of insightful questions that revealed he had followed the talk better than any of the rest of us.” Lederberg's scientific interests ranged widely, from the search for life in space—he coined the word “exobiology”—to the threat of emerging infectious diseases. Lederberg and Robert Shope edited Emerging Infections: Microbial Threats to Health in the United States, which was published in 1992 and credited with galvanising scientific and political interest in such infections. His weekly column in The Washington Post, which ran from 1966 to 1971, was concerned with issues such as the ethics of science and scientific understanding, and was an extension of his work as a scientific advisor to US Presidents; he eventually advised nine. In the 1950s, Lederberg began what would become a life-long collaboration with Eugene Garfield, founder of the Institute for Scientific Information and considered the father of citation analysis. Garfield credits a 1959 letter from Lederberg for encouraging him forward. “Since you first published your scheme for a ‘citation index’ in Science about 4 years ago I have been thinking very seriously about it, and must admit I am completely sold”, Lederberg wrote. Garfield went on to found The Scientist, in 1986, and Lederberg would remain an active chair of the magazine's scientific advisory board. I myself, who was an editor at The Scientist from 2002 until this month, remember Lederberg's keen ability to bring together seemingly disparate fields of science. In 1978, Lederberg became President of the Rockefeller University in New York, a position he would hold until 1990. He continued working at Rockefeller until shortly before his death. Lederberg and Zimmer divorced in 1966. He is survived by his second wife, Marguerite Lederberg, and two children.