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Rosalind Elsie Franklin (25 July, 1920 Kensington, London – 16 April, 1958 Chelsea, London) was an English biophysicist and crystallographer who made important contributions to the understanding of the fine structures of DNA, viruses, coal and graphite. Franklin is best known for her work on the X-ray diffraction images of DNA which formed the framework of Watson and Crick's hypothesis of the double helical structure of DNA in their 1953 publication, and when published constituted critical evidence of the hypothesis. Later she led pioneering work on the tobacco mosaic and polio viruses. She died in 1958 of bronchopneumonia, secondary carcinomatosis, and cancer of the ovary.
Additional recommended knowledge
Franklin was born in Kensington, London  into an affluent and influential British-Jewish family. Her uncle was Herbert Samuel (later Viscount Samuel) who was Home Secretary in 1916 and the first practising Jew to serve in the British Cabinet. He was also the first High Commissioner (effectively governor) for the British Mandate of Palestine.
Her aunt Helen was married to Norman Bentwich, who was Attorney General in the British Mandate of Palestine. She was active in trade union organization and women's suffrage, and was later a member of the London County Council.
Franklin was educated at St Paul's Girls' School where she excelled in Latin and sport. Her family were actively involved with a Working Men's College, where Ellis Franklin, her father, taught electricity, magnetism and the history of the Great War in the evenings and later became vice principal. Later they helped settle Jewish refugees from Europe who had escaped the Nazis.
In the summer of 1938 Franklin went to Newnham College, Cambridge. She passed her finals in 1941, but was only awarded a decree titular, as women were not entitled to degrees (BA Cantab.) from Cambridge at the time. In 1945 Rosalind Franklin received her PhD from Cambridge for her thesis on holes in coal.
British Coal Utilisation Research Association
She worked for Ronald Norish between 1941 and 1942. Because of her desire to work during World War II, she worked at the British Coal Utilisation Research Association in Kingston-upon-Thames from August 1942, studying the porosity of coal. Her work helped spark the idea of high-strength carbon fibres and was the basis of her doctoral degree-"The physical chemistry of solid organic colloids with special reference to coal and related materials" that she earned in 1945.
Laboratoire central des services chimiques de l'État
After the war ended Franklin accepted an offer to work in Paris with Jacques Mering. She learned x-ray diffraction techniques during her three years at the Laboratoire central des services chimiques de l'État. She seemed to have been very happy there and earned an international reputation based on her published research on the structure of coal. In 1950 she sought work in England and in June 1950 she was appointed to a position at King's College London.
King's College London
In January 1951, Franklin started working as a research associate at King's College London in the Medical Research Council's (MRC) Biophysics Unit, directed by John Randall. Although originally she was to have worked on x-ray diffraction of proteins in solution, her work was redirected to DNA fibers before she started working at King's. Maurice Wilkins and Raymond Gosling had been carrying out x-ray diffraction analysis of DNA in the Unit since 1950.
Franklin, working with her student Raymond Gosling started to apply her expertise in x-ray diffraction techniques to the structure of DNA. They discovered that there were two forms of DNA: at high humidity (when wet) the DNA fiber became long and thin, when it was dried it became short and fat. These were termed DNA 'B' and 'A' respectively. The work on DNA was subsequently divided, Franklin taking the A form to study and Wilkins the 'B' form. The x-ray diffraction pictures taken by Franklin at this time have been called, by J. D. Bernal, "amongst the most beautiful x-ray photographs of any substance ever taken".
By the end of 1951 it was generally accepted in King's that the B form of DNA was a helix, but Franklin in particular was unconvinced that the A form of DNA was helical in structure. As a practical joke Franklin and Gosling produced a death notice regretting the loss of helical crystalline DNA (A-DNA). During 1952 Rosalind Franklin and Raymond Gosling worked at applying the Patterson function to the x-ray pictures of DNA they had produced, this was a long and labour-intensive approach but would give an insight into the structure of the molecule. In February 1953 Francis Crick and James D. Watson of the Cavendish Laboratory in Cambridge University had started to build a model of the B form of DNA using similar data to that available to the team at King's. Model building had been applied successfully in the elucidation of the structure of the alpha helix by Linus Pauling in 1951, but Rosalind Franklin was opposed to building theoretical models, taking the view that building a model was only to be undertaken after the structure was known. Watson and Crick then indirectly obtained a prepublication version of Franklin's DNA X-ray diffraction data (possibly without her knowledge), and a prepublication manuscript by Pauling and Corey, giving them critical insights into the DNA structure.
Francis Crick and James Watson then published their model in Nature on 25 April 1953 in an article describing the double-helical structure of DNA with a small footnote to Franklin's data. Articles by Wilkins and Franklin illuminating their x-ray diffraction data published in the same issue of Nature supported the Crick and Watson model for the B form of DNA. Franklin eventually left King's College London in March 1953 to move to Birkbeck College in a move that had been planned for some time.
Birkbeck College, London
Franklin's work in Birkbeck involved the use of x-ray crystallography to study the structure of the tobacco mosaic virus (TMV) under J. D. Bernal and was funded by the Agricultural Research Council(ARC). In 1954 Franklin began a longstanding and successful collaboration with Aaron Klug. In 1955 Franklin had a paper published in the journal Nature, indicating that TMV virus particles were all of the same length, this was in direct contradiction to the ideas of the eminent virologist Norman Pirie, though her observation ultimately proved correct.
Franklin worked on rod like viruses such as TMV with her Ph.D. student Kenneth Holmes, while Aaron Klug worked on spherical viruses with his student John Finch, Franklin coordinated the work and was in charge. Franklin also had a research assistant, James Watt, subsidised by the National Coal Board and was now the Leader of the "ARC Group" at Birkbeck. By the end of 1955 her team had completed a model of the TMV and were working on viruses affecting several plants, including potato, turnip, tomato and pea. Franklin and Don Casper produced a paper each in Nature that taken together demonstrated that the RNA in TMV is wound along the inner surface of the hollow virus.
Illness and death
In the summer of 1956, while on a work related trip to the United States of America (USA) Franklin first began to suspect a health problem. An operation in September of the same year revealed two tumours in her abdomen. After this period of illness Franklin spent some time convalescing at the home of Crick and his wife Odile. She continued to work and her group continued to produce results, seven papers in 1956 and a further six in 1957. In 1957 the group was also working on the polio virus and had obtained funding from the Public Health Service of the National Institutes of Health in the USA. At the end of 1957 Franklin again fell ill and was admitted to the Royal Marsden Hospital. She returned to work in January 1958 and was given a promotion to Research Associate in Biophysics. She fell ill again on the 30th of March and died at Chelsea, London on April 16, 1958  . Exposure to X-ray radiation is sometimes considered a possible factor in her illness, though she was no more careless than other laboratory staff of the time. Other members of her family have died of cancer, and the incidence of cancer is known to be disproportionately high amongst Ashkenazi Jews.
She died in 1958 of bronchopneumonia, secondary carcinomatosis, and carcinoma of the ovary; her death certificate read (quote) "A Research Scientist, Spinster, Daughter of Ellis Arthur Franklin, a Banker."
Controversies after death
Various controversies have surrounded Rosalind Franklin; these have all come to light after her death.
Allegations of sexism at King's College
There have been allegations that Rosalind Franklin was discriminated against because of her gender.
One of the allegations is that King's, as an institution, was sexist. The allegation held that women were excluded from the staff dining room, and had to eat their meals in the student hall or away from the University. Whereas it is true that there was a dining room for the exclusive use of men (as was the case at other University of London colleges at the time), there was also a mixed gender dining room that overlooked the river Thames, and many male scientists refused to use the male only dining room owing to the preponderance of theologians. This notwithstanding, the fact remains that she was not given a choice in this regard, thus being effectively isolated from fellow scientists, a handicap that Watson and Crick certainly did not experience.
The other accusation regarding gender is that women were under-represented in John Randall's group; there was only one other woman in the group and that women were unfairly excluded. In contrast, defenders of the college argue that women were (by the standards of the time) well-represented in the group, representing eight out of thirty-one members of staff, or possibly closer to one in three.
Contribution to the model of DNA
Rosalind Franklin's contributions to the Crick and Watson model include an X-ray photograph of B-DNA (called photograph 51), that was briefly shown to James Watson by Maurice Wilkins in January 1953, and a report written for an MRC biophysics committee visit to King's in December 1952. The report contained data from the King's group, including some of Rosalind Franklin's work, and was given to Francis Crick by his thesis supervisor Max Perutz, a member of the visiting committee. Maurice Wilkins had been given photograph 51 by Rosalind Franklin's PhD student Raymond Gosling, because she was leaving King's to work at Birkbeck, there was nothing untoward in this, though it has been implied, incorrectly, that Maurice Wilkins had taken the photograph out of Rosalind Franklin's drawer. Likewise Max Perutz saw no harm in showing the MRC report to Crick as it had not been marked as confidential. Much of the important material contained in the report had been presented by Franklin in a talk she had given in November 1951, which Watson had attended. The upshot of all this was that when Crick and Watson started to build their model in February 1953 they were working with very similar data to those available at King's. Rosalind Franklin was probably never aware that her work had been used during construction of the model.
Recognition of her contribution to the model of DNA
On the completion of their model, Francis Crick and James Watson had invited Maurice Wilkins to be a co-author of their paper describing the structure. Wilkins turned down this offer, as he had taken no part in building the model. Maurice Wilkins later expressed regret that greater discussion of co-authorship had not taken place as this may have helped to clarify the contribution the work at King's had made to the discovery. There is no doubt that Franklin's experimental data were used by Crick and Watson to build their model of DNA in 1953 (see above). That she is not cited in their original paper outlining their model may be a question of circumstance, as it would have been very difficult to cite the unpublished work from the MRC report they had seen. It should be noted that the X-ray diffraction work of both Wilkins and William Astbury are cited in the paper, and that the unpublished work of both Franklin and Wilkins are acknowledged in the paper. Franklin and Raymond Gosling's own publication in the same issue of Nature was the first publications of this more clarified X-ray image of DNA.
The rules of the Nobel Prize forbid posthumous nominations, ; because Rosalind Franklin had died in 1958 she was not eligible for nomination to the Nobel Prize subsequently awarded to Crick, Watson, and Wilkins in 1962. The award was for their body of work on nucleic acids and not exclusively for the discovery of the structure of DNA. By the time of the award Wilkins had been working on the structure of DNA for over 10 years, and had done much to confirm the Crick-Watson model. Crick had been working on the genetic code at Cambridge and Watson had worked on RNA for some years.
a) on the base:
i) "These strands unravel during cell reproduction. Genes are encoded in the sequence of bases."
ii) "The double helix model was supported by the work of Rosalind Franklin and Maurice Wilkins."
b) on the helices:
i) "The structure of DNA was discovered in 1953 by Francis Crick and James Watson while Watson lived here at Clare."
ii) "The molecule of DNA has two helical strands that are linked by base pairs Adenine - Thymine or Guanine - Cytosine."
|This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Rosalind_Franklin". A list of authors is available in Wikipedia.|