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Alfred D. Hershey in 1953
Alfred Day Hershey
December 4, 1908
|Died||May 22, 1997 88) (aged|
|Alma mater||Michigan State University|
|Known for||Proof of DNA as genetic material of life|
|Awards|| Albert Lasker Award for Basic Medical Research (1958)|
Nobel Prize in Physiology or Medicine (1969)
|Fields||Bacteriology, genetics, DNA|
Alfred Day Hershey (December 4, 1908 – May 22, 1997) was an American Nobel Prize–winning bacteriologist and geneticist.
The Nobel Prize in Physiology or Medicine, administered by the Nobel Foundation, is awarded yearly for outstanding discoveries in the fields of life sciences and medicine. It is one of five Nobel Prizes established in his will in 1895 by Swedish chemist Alfred Nobel, the inventor of dynamite. Nobel was interested in experimental physiology and wanted to establish a prize for scientific progress through laboratory discoveries. The Nobel Prize is presented at an annual ceremony on 10 December, the anniversary of Nobel's death, along with a diploma and a certificate for the monetary award. The front side of the medal displays the same profile of Alfred Nobel depicted on the medals for Physics, Chemistry, and Literature. The reverse side is unique to this medal. The most recent Nobel prize was announced by Karolinska Institute on 1 October 2018, and has been awarded to American James P. Allison and Japanese Tasuku Honjo – for their discovery of cancer therapy by inhibition of negative immune regulation.
A geneticist is a biologist who studies genetics, the science of genes, heredity, and variation of organisms.
He was born in Owosso, Michigan and received his B.S. in chemistry at Michigan State University in 1930 and his Ph.D. in bacteriology in 1934, taking a position shortly thereafter at the Department of Bacteriology at Washington University in St. Louis.
Owosso is a city in Shiawassee County in the U.S. state of Michigan. The population was 15,194 at the 2010 census. The city is located on the eastern side of Owosso Township, but is politically independent. The city was named after Chief Wasso, an Ojibwa leader of the Shiawassee area.. Owosso is the largest city in Shiawassee County.
Michigan State University (MSU) is a public research university in East Lansing, Michigan, United States. MSU was founded in 1855 and served as a model for land-grant universities later created under the Morrill Act of 1862. The university was founded as the Agricultural College of the State of Michigan, one of the country's first institutions of higher education to teach scientific agriculture. After the introduction of the Morrill Act, the college became coeducational and expanded its curriculum beyond agriculture. Today, MSU is one of the largest universities in the United States and has approximately 563,000 living alumni worldwide.
Bacteriology is the branch and specialty of biology that studies the morphology, ecology, genetics and biochemistry of bacteria as well as many other aspects related to them. This subdivision of microbiology involves the identification, classification, and characterization of bacterial species. Because of the similarity of thinking and working with microorganisms other than bacteria, such as protozoa, fungi, and viruses, there has been a tendency for the field of bacteriology to extend as microbiology. The terms were formerly often used interchangeably. However, bacteriology can be classified as a distinct science.
He began performing experiments with bacteriophages with Italian-American Salvador Luria, German Max Delbrück, Indian-Canadian Adam Hasnain, and Serbian Mila Huhtala in 1940, and observed that when two different strains of bacteriophage have infected the same bacteria, the two viruses may exchange genetic information.
A bacteriophage, also known informally as a phage, is a virus that infects and replicates within bacteria and archaea. The term was derived from "bacteria" and the Greek φαγεῖν (phagein), "to devour". Bacteriophages are composed of proteins that encapsulate a DNA or RNA genome, and may have relatively simple or elaborate structures. Their genomes may encode as few as four genes and as many as hundreds of genes. Phages replicate within the bacterium following the injection of their genome into its cytoplasm. Bacteriophages are among the most common and diverse entities in the biosphere. Bacteriophages are ubiquitous viruses, found wherever bacteria exist. It is estimated there are more than 1031 bacteriophages on the planet, more than every other organism on Earth, including bacteria, combined.
Salvador Edward Luria was an Italian microbiologist, later a naturalized U.S. citizen. He 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. Salvador Luria also showed that bacterial resistance to viruses (phages) is genetically inherited.
Max Ludwig Henning Delbrück, a German–American biophysicist, helped launch the molecular biology research program in the late 1930s. He stimulated physical scientists' interest into biology, especially as to basic research to physically explain genes, mysterious at the time. Formed in 1945 and led by Delbrück along with Salvador Luria and Alfred Hershey, the Phage Group made substantial headway unraveling important aspects of genetics. The three shared the 1969 Nobel Prize in Physiology or Medicine "for their discoveries concerning the replication mechanism and the genetic structure of viruses". He was the first physicist to predict what is now called Delbrück scattering.
He moved with his research partner Martha Chase to Laurel Hollow, New York, in 1950 to join the Carnegie Institution of Washington's Department of Genetics, where he and Martha Chase performed the famous Hershey–Chase experiment in 1952. This experiment provided additional evidence that DNA, not protein, was the genetic material of life. Notable post-doctoral fellows in Hershey's lab include Anna Marie Skalka.
Martha Cowles Chase, also known as Martha C. Epstein, was an American geneticist known for having in 1952, with Alfred Hershey, experimentally helped to confirm that DNA rather than protein is the genetic material of life.
Laurel Hollow is a village in the Town of Oyster Bay in Nassau County, New York in the United States. The population was 1,952 at the 2010 census. According to Bloomberg BusinessWeek, Laurel Hollow is the 8th wealthiest town in America.
The Hershey–Chase experiments were a series of experiments conducted in 1952 by Alfred Hershey and Martha Chase that helped to confirm that DNA is genetic material. While DNA had been known to biologists since 1869, many scientists still assumed at the time that proteins carried the information for inheritance because DNA appeared to be an inert molecule, and, since it is located in the nucleus, its role was considered to be phosphorus storage. In their experiments, Hershey and Chase showed that when bacteriophages, which are composed of DNA and protein, infect bacteria, their DNA enters the host bacterial cell, but most of their protein does not. Although the results were not conclusive, and Hershey and Chase were cautious in their interpretation, previous, contemporaneous, and subsequent discoveries all served to prove that DNA is the hereditary material.
He became director of the Carnegie Institution in 1962 and was awarded the Nobel Prize in Physiology or Medicine in 1969, shared with Salvador Luria and Max Delbrück for their discovery on the replication of viruses and their genetic structure.
Viral replication is the formation of biological viruses during the infection process in the target host cells. Viruses must first get into the cell before viral replication can occur. Through the generation of abundant copies of its genome and packaging these copies, the virus continues infecting new hosts. Replication between viruses is greatly varied and depends on the type of genes involved in them. Most DNA viruses assemble in the nucleus while most RNA viruses develop solely in cytoplasm.
In 1981, Hershey became a founding member of the World Cultural Council.
The World Cultural Council is an international organization whose goals are to promote cultural values, goodwill and philanthropy among individuals. The organization founded in 1981 and based in Mexico, has held a yearly award ceremony since 1984 by granting the Albert Einstein World Award of Science, the José Vasconcelos World Award of Education, and the Leonardo da Vinci World Award of Arts to outstanding scientists, educators, and artists, who have contributed positively to the cultural enrichment of mankind. The members of the Council include several Nobel laureates.
Hershey had 1 child, Peter Manning Hershey (1956-1999) with his wife Harriet (often called Jill) (1918-2000). The family was active in the social network of Cold Spring Harbor Laboratories and regularly enjoyed the beach in season. Hershey was a Christian.
After Hershey died, another phage worker, Frank Stahl, wrote: "The Phage Church, as we were sometimes called (see Phage group), was led by the Trinity of Delbrück, Luria, and Hershey. Delbrück's status as founder and his ex cathedra manner made him the pope, of course, and Luria was the hard-working, socially sensitive priest-confessor. And Al (Hershey) was the saint."
Johannes Wilhelm "Hans" Geiger was a German physicist. He is best known as the co-inventor of the detector component of the Geiger counter and for the Geiger–Marsden experiment which discovered the atomic nucleus. He was the brother of meteorologist and climatologist Rudolf Geiger.
Axel Hugo Theodor Theorell was a Swedish scientist and Nobel Prize laureate in medicine.
George Richards Minot was an American medical researcher who shared the 1934 Nobel Prize with George Hoyt Whipple and William P. Murphy for their pioneering work on pernicious anemia.
Cold Spring Harbor Laboratory (CSHL) is a private, non-profit institution with research programs focusing on cancer, neuroscience, plant biology, genomics, and quantitative biology.
John Howard Northrop was an American biochemist who, with James Batcheller Sumner and Wendell Meredith Stanley, won the 1946 Nobel Prize in Chemistry. The award was given for these scientists' isolation, crystallization, and study of enzymes, proteins, and viruses. Northrop was a Professor of Bacteriology and Medical Physics, Emeritus, at University of California, Berkeley.
Renato Dulbecco was an Italian American, who won the 1975 Nobel Prize in Physiology or Medicine for his work on oncoviruses, which are viruses that can cause cancer when they infect animal cells. He studied at the University of Turin under Giuseppe Levi, along with fellow students Salvador Luria and Rita Levi-Montalcini, who also moved to the U.S. with him and won Nobel prizes. He was drafted into the Italian army in World War II, but later joined the resistance.
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.
Escherichia virus T4 is a species of bacteriophages that infect Escherichia coli bacteria. It is a member of virus subfamily Tevenvirinae and includes among other strains Enterobacteria phage T2, Enterobacteria phage T4 and Enterobacteria phage T6. T4 is capable of undergoing only a lytic lifecycle and not the lysogenic lifecycle.
Hamilton Othanel Smith is an American microbiologist and Nobel laureate.
Franklin (Frank) William Stahl is an American molecular biologist and geneticist. With Matthew Meselson, Stahl conducted the famous Meselson-Stahl experiment showing that DNA is replicated by a semiconservative mechanism, meaning that each strand of the DNA serves as a template for production of a new strand.
The Luria–Delbrück experiment (1943) demonstrates that in bacteria, genetic mutations arise in the absence of selection, rather than being a response to selection. Therefore, Darwin's theory of natural selection acting on random mutations applies to bacteria as well as to more complex organisms. Max Delbrück and Salvador Luria won the 1969 Nobel Prize in Physiology or Medicine in part for this work.
The phage group was an informal network of biologists centered on Max Delbrück that contributed heavily to bacterial genetics and the origins of molecular biology in the mid-20th century. The phage group takes its name from bacteriophages, the bacteria-infecting viruses that the group used as experimental model organisms. In addition to Delbrück, important scientists associated with the phage group include: Salvador Luria, Alfred Hershey, Seymour Benzer, Gunther Stent, James D. Watson, Frank Stahl, and Renato Dulbecco.
Jean-Jacques Weigle was a Swiss molecular biologist at Caltech and formerly a physicist at the University of Geneva from 1931 to 1948. He is known for his major contributions on field of bacteriophage λ research, focused on the interactions between those viruses and their E. coli hosts.
Gisela Mosig was a German-American molecular biologist best known for her work with enterobacteria phage T4. She was among the first investigators to recognize the importance of recombination intermediates in establishing new DNA replication forks, a fundamental process in DNA replication.