-
Alfred Hershey and Martha Chase
he Hershey–Chase experiments were a series of experiments conducted in 1952[1] by Alfred Hershey and Martha Chase that helped to confirm that DNA is the genetic material. While DNA had been known to biologists since 1869,[2] a few scientists still assumed at the time that proteins carried the information for inheritance. 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 mo -
Frederick Griffith
Frederick Griffith (c. 1879–1941) was a British bacteriologist whose focus was the epidemiology and pathology of bacterial pneumonia. In January 1928 he reported what is now known as Griffith's Experiment, the first widely accepted demonstrations of bacterial transformation, whereby a bacterium distinctly changes its form and function.[1] -
Beadle And Tatum
George W. Beadle (1903-1989) and Edward L. Tatum (1909-1975) show how genes direct the synthesis of enzymes that control metabolic processes -
Watson and Crick
Watson and Crick describe structure of DNA
1953 Photo: Model of DNA molecule
In the late nineteenth century, a German biochemist found the nucleic acids, long-chain polymers of nucleotides, were made up of sugar, phosphoric acid, and several nitrogen-containing bases. Later it was found that the sugar in nucleic acid can be ribose or deoxyribose, giving two forms: RNA and DNA. In 1943, American Oswald Avery proved that DNA carries genetic information. He even suggested DNA might actually be -
Oswald Avery: McCarty and MacLeod
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 (with the very word protein itself coined to indicate a belief that its function was primary). -
Max Ludwig Henning Delbrück
Max Ludwig Henning Delbrück, FRS[4] (4 September 1906 – 9 March 1981), 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 cell physiology. The three s -
Rosalind Franklin and Maurice Wilkins
Maurice Wilkins and Rosalind Franklin, together with Ray Gosling, Alec Stokes and Herbert Wilson and other colleagues at the Randall Institute at King's, made crucial contributions to the discovery of DNA's structure in 1953. -
Edwin Chargaff
Erwin Chargaff (11 August 1905 – 20 June 2002) was an Austrian biochemist who immigrated to the United States during the Nazi era and was a professor of biochemistry at Columbia University medical school.[1] Through careful experimentation, Chargaff discovered two rules that helped lead to the discovery of the double helix structure of DNA. Chargaff's rules state that DNA from any cell of all organisms should have a 1:1 ratio (base Pair Rule) of pyrimidine and purine bases and, more specificall -
Matthew Meselom and Frank Stahl
The Meselson–Stahl experiment was an experiment by Matthew Meselson and Franklin Stahl in 1958 which supported the hypothesis that DNA replication was semiconservative. In semiconservative replication, when the double stranded DNA helix is replicated each of the two new double-stranded DNA helixes consisted of one strand from the original helix and one newly synthesized. It has been called "the most beautiful experiment in biology. -
Arthur Kornburg
Arthur Kornberg (March 3, 1918 – October 26, 2007) was an American biochemist who won the Nobel Prize in Physiology or Medicine 1959 for his discovery of "the mechanisms in the biological synthesis of deoxyribonucleic acid (DNA)" together with Dr. Severo Ochoa of New York University. He was also awarded the Paul-Lewis Award in Enzyme Chemistry from the American Chemical Society in 1951, L.H.D. degree from Yeshiva University in 1962, as well as National Medal of Science in 1979 -
Marshall Nirenburg
(April 10, 1927 – January 15, 2010)[1] was an American biochemist and geneticist. He shared a Nobel Prize in Physiology or Medicine in 1968 with Har Gobind Khorana and Robert W. Holley for "breaking the genetic code" and describing how it operates in protein synthesis. In the same year, together with Har Gobind Khorana, he was awarded the Louisa Gross Horwitz Prize from Columbia University. -
Paul Berg
Paul Berg (1926-) creates first recombinant DNA molecules Paul Berg assembled the first DNA molecules that combined genes from different organisms. Results of his experiments, published in 1972, represented crucial steps in the subsequent development of recombinant genetic engineering. By stepwise methods such as he devised, individual genes could be isolated and inserted into mammalian cells or into such rapidly growing organisms as bacteria. The genes themselves could then be studied, and the -
Stanley Cohen and Herbert Boyer
Herbert Boyer and Stanley Cohen combined their efforts in biotechnology to invent a method of cloning genetically engineered molecules in foreign cells. By this discovery and its applications Boyer and Cohen initiated what is now the multibillion-dollar biotechnology industry. -
Kary Mullis
Kary Banks Mullis (born December 28, 1944) is a Nobel Prize-winning American biochemist, author, and lecturer. In recognition of his improvement of the polymerase chain reaction (PCR) technique, he shared the 1993 Nobel Prize in Chemistry with Michael Smith[1] and earned the Japan Prize in the same year. The process was first described by Kjell Kleppe and 1968 Nobel laureate H. Gobind Khorana, and allows the amplification of specific DNA sequences.[2][3][4] The improvements made by Mullis allowe
