Tuesday, October 22, 2019

Rosalind Franklin Discovered DNA Structure

Rosalind Franklin Discovered DNA Structure Rosalind Franklin is known for her role (largely unacknowledged during her lifetime) in discovering the helical structure of DNA, a discovery credited to Watson, Crick, and Wilkins- received a Nobel Prize for physiology and medicine in 1962.  Franklin might have been included in that prize, had she lived.  She was born on July 25, 1920, and died on April 16, 1958.  she was a biophysicist, physical chemist, and molecular biologist. Early Life Rosalind Franklin was born in London. Her family was well-off; her father worked as a banker with socialist leanings and taught at the Working Mens College. Her family was active in the public sphere. A paternal great-uncle was the first practicing Jew to serve in the British Cabinet. An aunt was involved with the womens suffrage movement and trade union organizing. Her parents were involved in resettling Jews from Europe. Studies Rosalind Franklin developed her interest in science at school, and by age 15 she decided to become a chemist. She had to overcome the opposition of her father, who did not want her to attend college or become a scientist; he preferred that she go into social work. She earned her Ph.D. in chemistry in 1945 at Cambridge. After graduating, Rosalind Franklin stayed and worked for a while at Cambridge and then took a job in the coal industry, applying her knowledge and skill to the structure of coal. She went from that position to Paris, where she worked with Jacques Mering and developed techniques in x-ray crystallography, a leading-edge technique to explore the structure of the atoms in molecules. Studying DNA Rosalind Franklin joined the scientists at the Medical Research Unit, Kings College when John Randall recruited her to work on the structure of DNA. DNA (deoxyribonucleic acid) was originally discovered in 1898 by Johann Miescher, and it was known that it was a key to genetics. But it was not until the middle of the 20th century when scientific methods had developed to where the actual structure of the molecule could be discovered, and Rosalind Franklins work was key to that methodology. Rosalind Franklin worked on the DNA molecule from 1951 until 1953. Using x-ray crystallography, she took photographs of the B version of the molecule. A co-worker with whom Franklin did not have a good working relationship, Maurice H.F. Wilkins, showed Franklins photographs of DNA to James Watson- without Franklins permission. Watson and his research partner Francis Crick were working independently on the structure of DNA, and Watson realized that these photographs were the scientific evidence they needed to prove that the DNA molecule was a double-stranded helix. While Watson, in his account of the discovery of the structure of DNA, largely dismissed Franklins role in the discovery, Crick later admitted that Franklin had been only two steps away from the solution herself. Randall had decided that the lab would not work with DNA, and so by the time her paper was published, she had moved on to Birkbeck College and the study of the structure of the tobacco mosaic virus, and she showed the helix structure of the virus RNA. She worked at Birkbeck for John Desmond Bernal and with Aaron Klug, whose 1982 Nobel Prize was based in part on his work with Franklin. Cancer In 1956, Franklin discovered she had tumors in her abdomen. She continued to work while undergoing treatment for cancer. She was hospitalized at the end of 1957, returned to work in early 1958, but soon became unable to work. She died in April. Rosalind Franklin did not marry or have children; she conceived of her choice to go into science as giving up marriage and children. Legacy Watson, Crick, and Wilkins were awarded the Nobel Prize in physiology and medicine in 1962, four years after Franklin died. The Nobel Prize rules limit the number of people for an award to three and also limit the award to those who are still alive, so Franklin was not eligible for the Nobel. Nevertheless, many have thought that she deserved explicit mention in the award and that her key role in confirming the structure of DNA was overlooked because of her early death and the attitudes of the scientists of the time toward women scientists. Watsons book recounting his role in the discovery of DNA displays his dismissive attitude toward Rosy. Cricks description of Franklins role was less negative than Watsons, and Wilkins mentioned Franklin when he accepted the Nobel. Anne Sayre wrote a biography of Rosalind Franklin, responding to the lack of credit given to her and the descriptions of Franklin by Watson and others. The wife of another scientist at the laboratory and a friend of Franklin, Sayre describes the clash of personalities and the sexism that Franklin faced in her work. Aaron Klug used Franklins notebooks to show how close she had come to independently discovering the structure of DNA. In 2004, the Finch University of Health Sciences/The Chicago Medical School changed its name to the Rosalind Franklin University of Medicine and Science to honor Franklins role in science and medicine. Career Highlights Fellowship, Cambridge, 1941-42: gas-phase chromatography, working with Ronald Norrish (Norrish won a 1967 Nobel in chemistry)British Coal Utilisation Research Association, 1942-46: studied physical structure of coal and graphiteLaboratoire Central des Services Chimiques de lEtat, Paris, 1947-1950: worked with x-ray crystallography, working with Jacques MeringMedical Research Unit, Kings College, London; Turner-Newall fellowship, 1950-1953: worked on the structure of DNABirkbeck College, 1953-1958; studied tobacco mosaic virus and RNA Education St. Pauls Girls School, London: one of the few schools for girls that included scientific studyNewnham College, Cambridge, 1938-1941, graduated 1941 in chemistryCambridge, Ph.D. in chemistry, 1945 Family Father: Ellis FranklinMother: Muriel Waley FranklinRosalind Franklin was one of four children, the only daughter Religious Heritage: Jewish, later became an agnostic Also known as:  Rosalind Elsie Franklin, Rosalind E. Franklin Key Writings by or About Rosalind Franklin Rosalind Franklin and Raymond G. Gosling [research student working with Franklin]. Article in Nature published April 25, 1953, with Franklins photograph of the B form of DNA. In the same issue as Watson and Cricks article announcing the double-helix structure of DNA.J. D. Bernal. Dr. Rosalind E. Franklin. Nature 182, 1958.James D. Watson. The Double Helix. 1968.Aaron Klug, Rosalind Franklin and the discovery of the structure of DNA. Nature 219, 1968.Robert Olby. The Path to the Double Helix. 1974.Anne Sayre. Rosalind Franklin and DNA. 1975.Brenda Maddox. Rosalind Franklin: The Dark Lady of DNA. 2002.

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