Rosalind Franklin crystallographer died 50 years ago
Rosalind Franklin died 50 years ago , aged 37, on April 16th 1958, of ovarian cancer and related conditions, which had become first apparent in the summer of 1956.
Working with Maurice Wilkins at Kings College London , through very skilled experimental work, in altering humidity, she identified two types of DNA, A and B which were mixed up Wilkin's crystallographic prints. Having made this distinction she worked on the B type molecule and her graduate student Raymond Gosling worked on the crystalline A type.
As a consequence she was one of a group of scientists whose work finally elucidated the physical structure of DNA. Her contribution , essentially revolves around the exact way James Watson obtained site of an X ray photograph produced by Rosalind Franklin of the B or wet type of DNA molecules called photo 51 - which has been claimed to surreptitious and without her consent or knowledge. see The Double Helix by James Watson
"The instant I saw the picture, my mouth fell open and my pulse began to race.
The pattern was unbelievably simpler than those obtained previously ("A" form).
Moreover the black cross of reflections which dominated the picture could arise
only from a helical structure. With the A form, the argument for a helixwas
never straightforward.... With the B form, however, mere inspection of its X-ray
picture gave several of the vital helical parameters"
J D Bernal was later to describe these x ray diffraction photographs as, "amongst the most beautiful x-ray photographs of any substance ever taken".
Crick who had worked on the structure of Haemoglobin realised from Franklin's photographs that they predicated base pairs, along with Erwin Chargaff's essential discovery on the equivalence of the AC / GT pairs, and the double helix structure was rapidly unravelled - and with it the elegant solution to understanding replication of the DNA molecule at mitosis.
Whatever the truth, of it's genesis , in an unorthodox fashion Watson and Crick realised this photo re-inforced their stunning and original insight that DNA was a double helix (and also their desire to beat Linus Pauling who had previously suggested a tricyclic helix)which they published as a letter in Nature in 1953 - "A Structure for Deoxyribose Nucleic Acid" by J D Watson and F H C Crick. Nature 1953, 171:737-738 .. and the rest as they say is history.
A more detailed history can be found here Friday, July 20, 2007 Watson + Crick DNA / LSD / X rays and Serendipity in Science because it appears that not only Wilkins photgraphs helped them but also the novel uses of the recently discovered hallucinogen LSD, which Crick was in later life claim that it fuelled their scientific insight ... and not a few parties at which the louche ladies man would ingest.
Anyway in 1961 3 years later Watson, Crick and Wilkins received the Nobel prize for Physiology and Medecine "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material"
As Nobel Prizes are never awarded to more than a group of 3 people or posthumously Wilkins was denied a prize that many felt she was due. Including Aaron Klug ( who received the OM in 1995 and "for his development of crystallographic electron microscopy and his structural elucidation of biologically important nucleic acid-protein complexes" the Nobel price for Chemistry in 1982) who felt that the Nobel committee shoudl have given Watson and Crick the Physiology and Medicine Prize and Wilkins and Franklin the Chemistry prize.
Rosalind Franklin was a single minded, determined woman, she suffered in a predominantly male collegiate atmosphere and she did not suffer fools gladly. An Ashkenazi Jew born in 1920, the second of 5 children and first daughter to Ellis and Muriel Franklin who lived the comfortable London suburban life of prosperous merchant bankers and with powerful and influential relatives such as her great uncle , Herbert Samuel and her mother's cousin the Chinese scholar Arthur Waley. They believed girls were educated to get married and do charitable social work in adult life, Roslind was not prepared to go along with this - which didn't please her dad.
It seems remarkable today that when she received her degree at Cambridge in 1941 it was "titular" degree as degrees were not then awarded to women.
Brenda Maddox wrote a biography Rosalind Franklin: The Dark Lady of DNA (Amazon) in which she argues that sexism, egotism and anti-Semitism conspired to marginalize a brilliant and uncompromising young scientist. The book is also a dreadful feminist tract which fails to understand the way that in scientific research there is an interplay between (invariably) strong minded, very clever people in whom a streak of ruthless endeavour is a necessary and vital part of the mix. (You don't sharpen an axe without causing a few sparks)
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