Lederberg in New Delhi, India
|5thPresident of Rockefeller University|
|Preceded by||Frederick Seitz|
|Succeeded by||David Baltimore|
|Born||May 23, 1925|
Montclair, New Jersey
|Died||February 2, 2008 82) (aged|
New York City
|Spouse(s)|| Esther Miriam Zimmer (1946–1966; divorced)|
Marguerite Stein Kirsch (1968–2008; 1 child, 1 stepchild)
|Alma mater|| Stuyvesant High School |
|Known for|| Neurospora crassa |
|Awards|| Nobel Prize in Physiology or Medicine (1958)|
National Medal of Science (1989)
Presidential Medal of Freedom (2006)
|Thesis||Genetic recombination in Escherichia coli (1947)|
|Doctoral advisor||Edward Tatum|
|Doctoral students||Norton Zinder|
Joshua Lederberg, ForMemRS(May 23, 1925 – February 2, 2008) was an American molecular biologist known for his work in microbial genetics, artificial intelligence, and the United States space program. He was 33 years old when he won the 1958 Nobel Prize in Physiology or Medicine for discovering that bacteria can mate and exchange genes (bacterial conjugation). He shared the prize with Edward Tatum and George Beadle, who won for their work with genetics.
In addition to his contributions to biology, Lederberg did extensive research in artificial intelligence. This included work in the NASA experimental programs seeking life on Mars and the chemistry expert system Dendral.
Lederberg was born in Montclair, New Jersey, to a Jewish family, son of Esther Goldenbaum Schulman Lederberg and Rabbi Zvi Hirsch Lederberg, in 1925, and moved to Washington Heights, Manhattan as an infant.He had two younger brothers. Lederberg graduated from Stuyvesant High School in New York City at the age of 15 in 1941. After graduation, he was allowed lab space as part of the American Institute Science Laboratory, a forerunner of the Westinghouse Science Talent Search. He enrolled in Columbia University in 1941, majoring in zoology. Under the mentorship of Francis J. Ryan, he conducted biochemical and genetic studies on the bread mold Neurospora crassa . Intending to receive his MD and fulfill his military service obligations, Lederberg worked as a hospital corpsman during 1943 in the clinical pathology laboratory at St. Albans Naval Hospital, where he examined sailors' blood and stool samples for malaria. He went on to receive his undergraduate degree in 1944.
Joshua Lederberg began medical studies at Columbia's College of Physicians and Surgeons while continuing to perform experiments. Inspired by Oswald Avery's discovery of the importance of DNA, Lederberg began to investigate his hypothesis that, contrary to prevailing opinion, bacteria did not simply pass down exact copies of genetic information, making all cells in a lineage essentially clones. After making little progress at Columbia, Lederberg wrote to Edward Tatum, Ryan's post-doctoral mentor, proposing a collaboration. In 1946 and 1947, Lederberg took a leave of absence to study under the mentorship of Tatum at Yale University. Lederberg and Tatum showed that the bacterium Escherichia coli entered a sexual phase during which it could share genetic information through bacterial conjugation.With this discovery and some mapping of the E. coli chromosome, Lederberg was able to receive his Ph.D. from Yale University in 1947. Joshua married Esther Miriam Zimmer (herself a student of Edward Tatum) on December 13, 1946.
Instead of returning to Columbia to finish his medical degree, Lederberg chose to accept an offer of an assistant professorship in genetics at the University of Wisconsin–Madison. His wife Esther Lederberg went with him to Wisconsin. She received her doctorate there in 1950.
Joshua Lederberg and Norton Zinder showed in 1951 that genetic material could be transferred from one strain of the bacterium Salmonella typhimurium to another using viral material as an intermediary step.This process is called transduction. In 1956, M. Laurance Morse, Esther Lederberg and Joshua Lederberg also discovered specialized transduction. The research in specialized transduction focused upon lambda phage infection of E. coli. Transduction and specialized transduction explained how bacteria of different species could gain resistance to the same antibiotic very quickly.
During her time in Joshua Lederberg's laboratory, Esther Lederberg also discovered fertility factor F, later publishing with Joshua Lederberg and Luigi Luca Cavalli-Sforza. In 1956, the Society of Illinois Bacteriologists simultaneously awarded Joshua Lederberg and Esther Lederberg the Pasteur Medal, for "their outstanding contributions to the fields of microbiology and genetics".
In 1957, Joshua Lederberg founded the Department of Medical Genetics at the University of Wisconsin–Madison. He has held visiting professorship in Bacteriology at the University of California, Berkeley in summer 1950and University of Melbourne (1957). Also in 1957, he was elected to the National Academy of Sciences.
Sir Gustav Nossal views Lederberg as his mentor, describing him as "lightning fast" and "loving a robust debate."
In 1958, Joshua Lederberg received the Nobel Prize and moved to Stanford University, where he was the founder and chairman of the Department of Genetics. He collaborated with Frank Macfarlane Burnet to study viral antibodies. With the launching of Sputnik in 1957, Lederberg became concerned about the biological impact of space exploration. In a letter to the National Academies of Sciences, he outlined his concerns that extraterrestrial microbes might gain entry to Earth onboard spacecraft, causing catastrophic diseases. He also argued that, conversely, microbial contamination of manmade satellites and probes may obscure the search for extraterrestrial life. He advised quarantine for returning astronauts and equipment and sterilization of equipment prior to launch. Teaming up with Carl Sagan, his public advocacy for what he termed exobiology helped expand the role of biology in NASA.
In the 1960s, he collaborated with Edward Feigenbaum in Stanford's computer science department to develop DENDRAL.
In 1978, he became the president of Rockefeller University, until he stepped down in 1990 and became professor-emeritus of molecular genetics and informatics at Rockefeller University, reflecting his extensive research and publications in these disciplines.
Throughout his career, Lederberg was active as a scientific advisor to the U.S. government. Starting in 1950, he was a member of various panels of the Presidential Science Advisory Committee. In 1979, he became a member of the U.S. Defense Science Board and the chairman of President Jimmy Carter's President's Cancer Panel. In 1989, he received National Medal of Science for his contributions to the scientific world. In 1994, he headed the Department of Defense's Task Force on Persian Gulf War Health Effects, which investigated Gulf War Syndrome.
Lederberg married fellow scientist Esther Miriam Zimmer in 1946; they divorced in 1966. He married psychiatrist Marguerite Stein Kirsch in 1968. He was survived by Marguerite, their daughter, Anne Lederberg, and his stepson, David Kirsch.
Escherichia coli, also known as E. coli, is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus Escherichia that is commonly found in the lower intestine of warm-blooded organisms (endotherms). Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in their hosts, and are occasionally responsible for product recalls due to food contamination. The harmless strains are part of the normal microbiota of the gut, and can benefit their hosts by producing vitamin K2, (which helps blood to clot) and preventing colonisation of the intestine with pathogenic bacteria, having a symbiotic relationship. E. coli is expelled into the environment within fecal matter. The bacterium grows massively in fresh fecal matter under aerobic conditions for 3 days, but its numbers decline slowly afterwards.
Oswald Theodore Avery Jr. was a Canadian-American physician and medical researcher. The major part of his career was spent at the Rockefeller University Hospital in New York City. Avery was one of the first molecular biologists and a pioneer in immunochemistry, but he is best known for the experiment that isolated DNA as the material of which genes and chromosomes are made.
Barbara McClintock was an American scientist and cytogeneticist who was awarded the 1983 Nobel Prize in Physiology or Medicine. McClintock received her PhD in botany from Cornell University in 1927. There she started her career as the leader in the development of maize cytogenetics, the focus of her research for the rest of her life. From the late 1920s, McClintock studied chromosomes and how they change during reproduction in maize. She developed the technique for visualizing maize chromosomes and used microscopic analysis to demonstrate many fundamental genetic ideas. One of those ideas was the notion of genetic recombination by crossing-over during meiosis—a mechanism by which chromosomes exchange information. She produced the first genetic map for maize, linking regions of the chromosome to physical traits. She demonstrated the role of the telomere and centromere, regions of the chromosome that are important in the conservation of genetic information. She was recognized as among the best in the field, awarded prestigious fellowships, and elected a member of the National Academy of Sciences in 1944.
Dendral was a project in artificial intelligence (AI) of the 1960s, and the computer software expert system that it produced. Its primary aim was to study hypothesis formation and discovery in science. For that, a specific task in science was chosen: help organic chemists in identifying unknown organic molecules, by analyzing their mass spectra and using knowledge of chemistry. It was done at Stanford University by Edward Feigenbaum, Bruce G. Buchanan, Joshua Lederberg, and Carl Djerassi, along with a team of highly creative research associates and students. It began in 1965 and spans approximately half the history of AI research.
Pathophysiology – a convergence of pathology with physiology – is the study of the disordered physiological processes that cause, result from, or are otherwise associated with a disease or injury. Pathology is the medical discipline that describes conditions typically observed during a disease state, whereas physiology is the biological discipline that describes processes or mechanisms operating within an organism. Pathology describes the abnormal or undesired condition, whereas pathophysiology seeks to explain the functional changes that are occurring within an individual due to a disease or pathologic state.
The Rockefeller University is a private graduate university in New York City. It focuses primarily on the biological and medical sciences and provides doctoral and postdoctoral education. Rockefeller is the oldest biomedical research institute in the United States. The 82-person faculty has 37 members of the National Academy of Sciences, 17 members of the National Academy of Medicine, seven Lasker Award recipients, and five Nobel laureates. As of October 2019, a total of 36 Nobel laureates have been affiliated with Rockefeller University.
Transduction is the process by which foreign DNA is introduced into a bacterial cell by a virus or viral vector. An example is the viral transfer of DNA from one bacterium to another and hence an example of horizontal gene transfer. Transduction does not require physical contact between the cell donating the DNA and the cell receiving the DNA, and it is DNase resistant. Transduction is a common tool used by molecular biologists to stably introduce a foreign gene into a host cell's genome.
George Wells Beadle was an American geneticist. In 1958 he shared one-half of the Nobel Prize in Physiology or Medicine with Edward Tatum for their discovery of the role of genes in regulating biochemical events within cells. He also served as the 7th President of the University of Chicago.
Werner Arber is a Swiss microbiologist and geneticist. Along with American researchers Hamilton Smith and Daniel Nathans, Werner Arber shared the 1978 Nobel Prize in Physiology or Medicine for the discovery of restriction endonucleases. Their work would lead to the development of recombinant DNA technology.
Edward Lawrie Tatum was an American geneticist. He shared half of the Nobel Prize in Physiology or Medicine in 1958 with George Beadle for showing that genes control individual steps in metabolism. The other half of that year's award went to Joshua Lederberg.
Stanley Norman Cohen is an American geneticist and the Kwoh-Ting Li Professor in the Stanford University School of Medicine. Stanley Cohen and Herbert Boyer were the first scientists to transplant genes from one living organism to another, a fundamental discovery for genetical engineering. Thousands of products have been developed on the basis of their work, including human growth hormone and hepatitis B vaccine. According to microbiologist Hugh McDevitt, "Cohen's DNA cloning technology has helped biologists in virtually every field". Without it, "the face of biomedicine and biotechnology would look totally different."
Norton David Zinder was an American biologist famous for his discovery of genetic transduction. Zinder was born in New York City, received his Ph.D. from the University of Wisconsin–Madison, and became a member of the National Academy of Sciences in 1969. He led a lab at Rockefeller University until shortly before his death.
Julius Adler Ph.D. is an American biochemist. He has been an Emeritus Professor of biochemistry and genetics at the University of Wisconsin–Madison since 1997.
The fertility factor allows genes to be transferred from one bacterium carrying the factor to another bacterium lacking the factor by conjugation. The F factor is carried on the F episome, the first episome to be discovered. Unlike other plasmids, F factor is constitutive for transfer proteins due to a mutation in the gene finO. The F plasmid belongs to a class of conjugative plasmids that control sexual functions of bacteria with a fertility inhibition (Fin) system.
Esther Miriam Zimmer Lederberg was an American microbiologist and a pioneer of bacterial genetics. Notable contributions include the discovery of the bacterial virus λ, the transfer of genes between bacteria by specialized transduction, the development of replica plating, and the discovery of the bacterial fertility factor F.
Bernard Ogilvie Dodge was an American botanist and pioneer researcher on heredity in fungi. Dodge was the author of over 150 papers dealing with the life histories, cytology, morphology, pathology and genetics of fungi, and with insects and other animal pests of plants. He made the first studies of sexual reproduction in the common bread mold, Neurospora.
The Avery–MacLeod–McCarty experiment was an experimental demonstration, reported in 1944 by Oswald Avery, Colin MacLeod, and Maclyn McCarty, that DNA is the substance that causes bacterial transformation, in an era when it had been widely believed that it was proteins that served the function of carrying genetic information. It was the culmination of research in the 1930s and early 20th Century at the Rockefeller Institute for Medical Research to purify and characterize the "transforming principle" responsible for the transformation phenomenon first described in Griffith's experiment of 1928: killed Streptococcus pneumoniae of the virulent strain type III-S, when injected along with living but non-virulent type II-R pneumococci, resulted in a deadly infection of type III-S pneumococci. In their paper "Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Desoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III", published in the February 1944 issue of the Journal of Experimental Medicine, Avery and his colleagues suggest that DNA, rather than protein as widely believed at the time, may be the hereditary material of bacteria, and could be analogous to genes and/or viruses in higher organisms.
The Matilda effect is a bias against acknowledging the achievements of those women scientists whose work is attributed to their male colleagues. This effect was first described by suffragist and abolitionist Matilda Joslyn Gage (1826–98) in her essay, "Woman as Inventor". The term "Matilda effect" was coined in 1993 by science historian Margaret W. Rossiter.
Zygotic induction occurs when a bacterial cell carrying the silenced DNA of a bacterial virus in its chromosome transfers the viral DNA along with its own DNA to another bacterial cell lacking the virus, causing the recipient of the DNA to break open. In the donor cell, a repressor protein encoded by the prophage keeps the viral genes turned off so that virus is not produced. When DNA is transferred to the recipient cell by conjugation, the viral genes in the transferred DNA are immediately turned on because the recipient cell lacks the repressor. As a result, lots of virus is made in the recipient cell, and lysis eventually occurs to release the new virus.
Escherichia coli is a Gram-negative gammaproteobacterium commonly found in the lower intestine of warm-blooded organisms (endotherms). The descendants of two isolates, K-12 and B strain, are used routinely in molecular biology as both a tool and a model organism.