Member SpotlightsIn Memory of a Nobel Leaurate Joshua Lederberg, Ph.D. The Science Advisory Board wishes to acknowledge the deceased Joshua Lederberg, Ph.D, who was awarded the Nobel Prize for Physiology or Medicine. The Science Advisory Board had the opportunity to interview Lederberg in a previous Member Spotlight, and in remembrance, the original interview has been brought to the forefront again:  Joshua Lederberg, Ph.D. approaches research today with the same ferocious and unbounded imagination tempered by critical examination that he employed during his early training at Columbia and Yale Universities. This remarkable combination of creativity and analysis were instrumental in his discovery, in conjunction with Edward Tatum, that bacteria exchange genetic material through sexual recombination. In 1958 (at the age of 33 ), he was awarded the Nobel Prize for Physiology or Medicine for his "discoveries concerning genetic recombination and the organization of the genetic material of bacteria." He shared the prize with George W. Beadle and Tatum. Their prize was "for their discovery that genes act by regulating definite chemical events". Currently, Dr. Lederberg is Professor Emeritus, Laboratory of Molecular Genetics and Informatics at Rockefeller University (New York). In addition to maintaining an active research program on the limits to rate of growth of bacteria, he also lectures and serves on a number of advisory panels on global health policy, biological warfare and the threat of bioterrorism. After his work with Tatum, Dr. Lederberg elected to leave medical school to earn a Ph.D. from Yale University. Upon completion of his graduate studies, Dr. Lederberg joined the Genetics Department at the University of Wisconsin, which was originally part of the University's School of Agriculture. During his tenure there, he helped form and then served as chair of the Department of Medical Genetics. Just before receiving the Nobel Prize, Dr. Lederberg was invited to join the new Department of Genetics at Stanford University's School of Medicine. In 1978, he was appointed President of Rockefeller University and later became professor emeritus in 1990. Dr. Lederberg's scientific contributions also include his discovery along with Norton D. Zinder of transduction (a virus-mediated form of bacterial genetic recombination); coining the term plasmid to denote extra-chromosomal genetic material; and the technique of replica plating. These discoveries were influential in making bacteria a fundamental tool for genetics research and paved the way for the advent of recombinant DNA technology. Dr. Lederberg has been involved in artificial intelligence research and in the NASA experimental programs seeking life on Mars. He has also been a consultant on health-related matters for government and the international community including WHO's Advisory Health Research Council. In 1998, he received the US National Medal of Science in 1989, where his consultative role was specifically recognized. He has been a member of the National Academy of Sciences since 1957, and a charter member of its Institute of Medicine, has served as Chairman of the President's Cancer Panel, and of the Congress' Technology Assessment Advisory Council. In all of his endeavors, Dr. Lederberg has devoted himself to enhancing human's understanding of nature. He still finds it thrilling to mentor young scientists, citing enjoyment of the dialectic that results from a close relationship between two inquiring minds. He professes a sense of pride in seeing his students grow and prosper as researchers in their own right. From the Los Angeles Times, we bring you more details on the life of Joshua Lederberg, Ph.D, and details of his death due to pneumonia on February 2, 2008. Joshua Lederberg, 82; genetics pioneer won Nobel Prize By Thomas H. Maugh II, Los Angeles Times Staff Writer February 5, 2008 Joshua Lederberg, who won a Nobel Prize for discovering that bacteria could have sex, thereby establishing the foundation of modern genetics and biotechnology, died of pneumonia Saturday in New York City. He was 82. The prodigy's pioneering work while he was still in graduate school made him one of the first researchers to manipulate genes in a living organism. It opened the door to an understanding of how bacteria evolved and the mechanisms by which they develop and transfer antibiotic resistance. It also set the stage for a long and fruitful career in space biology and artificial intelligence, as well as four decades on government advisory commissions on health policy, national security and arms control. As president of Rockefeller University in New York City from 1978 to 1990, he was instrumental in the renovation of many of the scientific research institution's facilities and the construction of new ones. "Josh was one of the most creative scientists of our times," said molecular biologist Stanley N. Cohen of Stanford University. "He thought more broadly and more deeply about more things than anyone I've ever known. His death is a loss to all of us." When Lederberg began his research immediately after World War II, biologists had a very limited understanding of genetics and bacterial reproduction. Pioneering molecular biologist Oswald Avery had discovered in 1944 that deoxyribonucleic acid, or DNA, was the material that encoded the genetic information of life, including bacteria. Inspired by the findings, Lederberg took a leave of absence from Columbia University medical school and began studying pneumococci and Escherichia coli with Edward L. Tatum of Yale University. At the time, bacteria were thought to be simple organisms that reproduced by cell division and thus produced offspring that were genetically identical to the parent -- that is, clones. Within a year, the pair were able to show that E. coli underwent a sexual stage in which it could mate and exchange genetic information, a process called recombination or conjugation. When bacteria in the sexual stage came into contact, they could exchange rings of DNA -- separate from their nuclear DNA -- that Lederberg dubbed plasmids. That nomenclature did not catch on until the 1970s, however, when it became clear that genes encoded in the plasmids were the mechanism by which bacteria transferred antibiotic resistance from one organism to another. In 1952, working with his student Norton D. Zinder, Lederberg identified a second mechanism for exchange of genes, called transduction. In transduction, viruses that infect bacteria remove one or more genes from the DNA of a bacterium and insert it into the genome of a second one. That finding was the first demonstration of the manipulation of an organism's genetic material and ultimately served as the basis for the techniques of genetic engineering. In 1958, at the age of 33, Lederberg was awarded half of the Nobel Prize in Physiology or Medicine. The other half was shared by Tatum and George Beadle, who were honored for their discovery in the 1940s that genes acted by regulating specific chemical processes. The fame conferred by the Nobel Prize allowed Lederberg to expand his interests. Following the launch of Sputnik in 1958, he began arguing that biologists should have a place in the exploration of space, coining the term "exobiology" to refer to the study of life outside Earth. With physicist Dean B. Cowle, he argued that astronauts and spacecraft returning to Earth should be quarantined to prevent a potentially catastrophic infection by extraterrestrial germs. They also argued that our own spacecraft be sterilized before launch to prevent the possible contamination of biological life on other planets. Both suggestions were adopted. Lederberg helped design and build automated instruments to detect signs of life on Mars as part of NASA's 1975 Viking mission. That, in turn, led him to advocate expanding the role of computers in science. He and Edward Feigenbaum of Stanford University developed a computer program called DENDRAL, designed to help identify unknown chemical compounds from spectroscopic and laboratory data. It was the first expert system for use in science. Among his many government advisory positions, he served as a consultant to the Arms Control and Disarmament Agency during the negotiation of the biological weapons disarmament treaty. In his later years, he spoke often about the threat to humankind from the potential emergence of multi-drug-resistant microorganisms. Among the many honors he received for his achievements were the National Medal of Science in 1998 and the Presidential Medal of Freedom in 2006, the nation's highest civilian award. Joshua Lederberg was born May 23, 1925, in Montclair, N.J., the son of Jewish immigrants from Palestine. A precocious child, by the age of 6 or 7 he had decided on science as a career, professing a desire to be "like Einstein." By the age of 11, he was reading college medical texts in the back of the classroom as his peers were pursuing more mundane subjects. He graduated from New York's prestigious Stuyvesant High School in 1941 at the age of 15 and enrolled as a zoology major at Columbia. At 17, he enlisted in the Navy's V-12 college training program, which featured a condensed pre-med and medical training program to produce doctors for the armed forces. He entered medical school at Columbia in 1944, but left after two years to work with Tatum. He had intended to return, but before he completed his doctorate in 1948, Lederberg was offered a position in the department of genetics at the University of Wisconsin, a post that would allow him to continue his research on bacteria. After a decade there, he was appointed chairman of the new genetics department of Stanford, where he spent 20 years before becoming president of Rockefeller University. Much of his work at Wisconsin and Stanford was performed in association with his first wife, the former Esther Miriam Zimmer, whom he met while working with Tatum. They were divorced in 1966. Lederberg is survived by his second wife, Dr. Marguerite S. Lederberg of New York; a daughter, Anned Lederberg of New York; and a stepson, David Kirsch of Chevy Chase, Md. ### << Previous Next >> [ View All Member Spotlights ] |
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