Structural Biochemistry/Rosalind Franklin

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Rosalind Elsie Franklin was famous for her research and discovery work for understanding the structure of DNA, RNA, viruses, coal, and graphite. She is best known for her work with x-ray crystallography and x-ray diffraction images of DNA which eventually led to the discovery of the double helix. She is most memorable for her contributions to the understanding of DNA. DNA is the foundation of genetics and the better understanding of its structure gives a better understanding of how genetics are endowed from parent to offspring. Although the research and images provided by her proved to be accurate and valuable in discovering the DNA structure, her contributions are often overlooked. Many of her unpublished drafts show that she located the phosphate groups of DNA. Unfortunately, Watson and Crick only hint at her contribution. In 1958, she died of ovarian cancer while leading research on the polio virus.

Early Life[edit]

Franklin was born on July 25, 1920 in Notting Hill London into an affluent family. Her father was a merchant banker at the time and her parents had five children, Rosalind being the eldest. According to her mother, Muriel Frances Waley, Rosalind always knew where she was going and at sixteen, she took science for her subject. At an early age, she demonstrated aptitude for math and science and foreign languages including French, Italian and German.

In 1938, 18 at the time, Rosalind started her college career at University of Cambridge. Three years later, she was awarded a bachelor's degree and received a research fellowship with R.G.W. Norrish at the National Cancer institute. Afterwards, she continued to work as a research assistant at the British Coal Utilisation Research Association (BCURA) with professor Norrish. She based her Ph. D. thesis on the porosity of coal, and after she wrote The Physical Chemistry of Solid Organic Colloids with Special Reference to Coal and five other papers, Cambridge University awarded her a Ph. D. in 1945.

Discovery[edit]

In 1951, she started working with John Randall at the King's College London. She worked on DNA fibers and experimental diffraction. Here, she was able to increase her skills with x-ray diffraction. In Randall's lab, she was partnered with Maurice Wilkins. Although they were both concerned with DNA, they led separate research groups and projects. Although the university was not very welcoming for women, Randall persisted on the DNA project and utilized her knowledge in x-ray crystallography to see different images of the DNA.

Franklin was an X-ray crystallographer. Her images of the x-ray diffraction of the DNA molecule led to a better understanding of the DNA structure. Her work had confirmed that the DNA is of a helical structure. She had purposed that there are two types of the DNA molecule, type A and type B. Furthermore, she determined the location of the phosphate groups and insisted that the backbones were on the outside of the structure.

Although she was very close to solving the complete structure of DNA, Watson and Crick beat her to the finish due to many bickers with Wilkins and herself. It is known that at one point, Wilkins showed Watson one of Franklin's x-ray portraits of the DNA and this served as the last missing puzzle piece for Watson and Crick.


Controversies[edit]

Although Franklin's work was mentioned in the published journal written by Watson and Crick, the amount of credit she deserves still remains questionable. There is no doubt that her data were used by Watson and Crick to build their model of DNA in 1953. Although she did have a meaningful role in proposing the structure of the DNA, many people argue that Watson and Crick already figured out the model on their own and that her portrait just 'confirmed' what they already knew. Instead of inviting Franklin to co-author their paper describing the structure, Watson and Crick invited Wilkins, who leaked Franklin's portrait to Watson, to co-author. Although Wilkins declined this offer, he later expressed his regret of denying this offer. She was never nominated for a Nobel Prize because she died of cancer in 1958. Instead, the prize subsequently went to Watson, Crick, and Wilkins.

References[edit]

http://profiles.nlm.nih.gov/ps/retrieve/Narrative/KR/p-nid/187

http://www.sdsc.edu/ScienceWomen/franklin.html