Photo 51 Explained

Photo 51 is an X-ray based fiber diffraction image of a paracrystalline gel composed of DNA fiber[1] taken by Raymond Gosling,[2] [3] a postgraduate student working under the supervision of Maurice Wilkins and Rosalind Franklin at King's College London, while working in Sir John Randall's group.[4] [5] [6] [7] The image was tagged "photo 51" because it was the 51st diffraction photograph that Franklin had taken.[8] It was critical evidence[9] in identifying the structure of DNA.[10]

Use in discovering structure of DNA

According to a later account by Raymond Gosling, although Photo 51 was an exceptionally clear diffraction pattern of the "B" form of DNA, Franklin was more interested in solving the diffraction pattern of the "A" form of DNA, so she put Gosling's Photo 51 to the side. When it had been decided that Franklin would leave King's College, Gosling showed the photograph to Maurice Wilkins[11] [12] (who would become Gosling's advisor after Franklin left).

A few days later, Wilkins showed the photo to James Watson after Gosling had returned to working under Wilkins' supervision. Franklin did not know this at the time because she was leaving King's College London. Randall, the head of the group, had asked Gosling to share all his data with Wilkins.[13] Watson recognized the pattern as a helix because his co-worker Francis Crick had previously published a paper of what the diffraction pattern of a helix would be. Watson and Crick used characteristics and features of Photo 51, together with evidence from multiple other sources, to develop the chemical model of the DNA molecule. Their model, along with papers by Wilkins and colleagues, and by Gosling and Franklin, were first published, together, in 1953, in the same issue of Nature.

In 1962, the Nobel Prize in Physiology or Medicine was awarded to Watson, Crick and Wilkins. The prize was not awarded to Franklin; she had died four years earlier, and although there was not yet a rule against posthumous awards,[14] the Nobel Committee generally does not make posthumous nominations.[15] Gosling's work also was not cited by the prize committee.

The photograph provided key information that was essential for developing a model of DNA. The diffraction pattern determined the helical nature of the double helix strands (antiparallel). The outside of the DNA chain has a backbone of alternating deoxyribose and phosphate moieties, and the base pairs, the order of which provides codes for protein building and thereby inheritance, are inside the helix. Watson and Crick's calculations from Gosling and Franklin's photography gave crucial parameters for the size and structure of the helix.

Photo 51 became a crucial data source[16] that led to the development of the DNA model and confirmed the prior postulated double helical structure of DNA, which were presented in the series of three articles in the journal Nature in 1953.

As historians of science have re-examined the period during which this image was obtained, considerable controversy has arisen over both the significance of the contribution of this image to the work of Watson and Crick, as well as the methods by which they obtained the image. Franklin had been hired independently of Maurice Wilkins, who, taking over as Gosling's new supervisor, showed Photo 51 to Watson and Crick without Franklin's knowledge. Whether Franklin would have deduced the structure of DNA on her own, from her own data, had Watson and Crick not obtained Gosling's image, is a hotly debated topic,[17] [18] [19] made more controversial by the negative caricature of Franklin presented in the early chapters of Watson's history of the research on DNA structure, The Double Helix.[20] [21] Watson admitted his distortion of Franklin in his book, noting in the epilogue: "Since my initial impressions about [Franklin], both scientific and personal (as recorded in the early pages of this book) were often wrong, I want to say something here about her achievements."[22]

Cultural references

See also

Notes and References

  1. Franklin. R. E.. Gosling. R. G.. 1953-09-10. The structure of sodium thymonucleate fibres. I. The influence of water content. Acta Crystallographica. 6. 8. 673–677. 10.1107/S0365110X53001939. 1953AcCry...6..673F . free.
  2. Due credit . Nature . 496 . 7445 . 270 . 18 April 2013 . 10.1038/496270a. 23607133 . free .
  3. Witkowski J . 2019 . The forgotten scientists who paved the way to the double helix . Nature . 568 . 7752. 308–309 . 10.1038/d41586-019-01176-9 . 2019Natur.568..308W . free .
  4. Attar . N . Raymond Gosling: the man who crystallized genes . Genome Biology . 2013 . 14 . 4 . 402 . 10.1186/gb-2013-14-4-402. 23651528 . 3663117 . free .
  5. Web site: DNA: the King's story . 2013-02-15 . https://web.archive.org/web/20130207222431/http://www.kingscollections.org/exhibitions/archives/dna/key-discoveries/momentum . 2013-02-07 . live .
  6. Web site: Secret of Photo 51. Nova . . 2017-09-08 . https://web.archive.org/web/20170831201252/http://www.pbs.org/wgbh/nova/photo51/ . 2017-08-31 . live .
  7. Book: The gene: a historical perspective . registration . PHOTO 51 rosalind franklin. . 85 . Greenwood Publishing Group . 2007 . 9780313334498 .
  8. PastCast: The other DNA papers . 26 April 2019 . 10.1038/d41586-019-01347-8 . 4 September 2019 . https://web.archive.org/web/20190605110254/https://www.nature.com/articles/d41586-019-01347-8 . 5 June 2019 . live . Smith . Kerri . Nature . 201414443 .
  9. Web site: Anatomy of Photo 51 . Krock . Lexi . NOVA online . . 22 April 2003 . 8 September 2017 . https://web.archive.org/web/20100729050654/http://www.pbs.org/wgbh/nova/photo51/anat-flash.html . 29 July 2010 . live .
  10. James D. . Watson . James D. Watson . Francis . Crick . Francis Crick . 1953 . A Structure for Deoxyribose Nucleic Acid . Nature . 171 . 737–738 . https://web.archive.org/web/20030403052855/http://www.nature.com/nature/dna50/watsoncrick.pdf . dead . 2003-04-03 . 10.1038/171737a0 . 13054692 . 4356. 1953Natur.171..737W . 4253007 .
  11. PastCast: The other DNA papers . 26 April 2019 . 10.1038/d41586-019-01347-8 . Raymond Gosling: 'I took it down the corridor and gave it to him because it had reached the stage now when Rosalind was going to leave, so she suggested that I go down the corridor and give this beautiful structure B pattern, this photo 51, to Maurice. Maurice couldn’t believe it when I offered it to him. He couldn’t believe that I hadn’t stolen it from her desk. He didn’t think that she could ever offer him something as interesting as this.' . 4 September 2019 . https://web.archive.org/web/20190605110254/https://www.nature.com/articles/d41586-019-01347-8 . 5 June 2019 . live . Smith . Kerri . Nature . 201414443 .
  12. Tobin . Martin J. . 2003-04-15 . April 25, 1953: Three Papers, Three Lessons . American Journal of Respiratory and Critical Care Medicine . en . 167 . 8 . 1047–1049 . 10.1164/rccm.2302011 . 12684243 . 1073-449X . On January 30, 1953, Watson visited King's. Without Franklin's permission, Wilkins showed her data to Watson—in particular, an X-ray crystallograph (of May 1952) that provided unquestionable evidence of the helical structure of DNA..
  13. Book: Williams . Gareth . Unravelling the Double Helix . 2019 . Pegasus Books . New York . 978-1-64313-215-0 . 264–267.
  14. Web site: Official Website of the Nobel Prizes . Nobel Prize Facts . 24 January 2016 . https://web.archive.org/web/20170708135926/https://www.nobelprize.org/nobel_prizes/facts/ . 8 July 2017 . live .
  15. News: My aunt, the DNA pioneer . BBC News . 24 April 2003 . 18 May 2011 . https://web.archive.org/web/20070828122335/http://news.bbc.co.uk/1/hi/sci/tech/2895681.stm . 28 August 2007 . live .
  16. "The instant I saw the picture my mouth fell open and my pulse began to race." James D. Watson (1968), The Double Helix, page 167. New York: Atheneum, Library of Congress card number 68-16217. Page 168 shows the X-shaped pattern of the B-form of DNA which provided details of the helical structure of DNA to both scientists Watson and Crick.
  17. Book: Maddox, Brenda . 2002 . Rosalind Franklin: The Dark Lady of DNA . registration . HarperCollins . 978-0-393-32044-2 .
  18. Max Perutz and the Secret of Life. Published in the UK by Chatto & Windus, and in the USA by the Cold Spring Harbor Laboratory Press.
  19. Book: Wilkins . Wilkins . M. . The Third Man of the Double Helix: An Autobiography . 2003 . Oxford University Press . Oxford .
  20. Book: Watson, James D. . The Double Helix: A Personal Account of the Discovery of the Structure of DNA . 1968 . Atheneum . 1980 . 978-0-689-70602-8 .
  21. Book: Sayre, Anne . Rosalind Franklin and DNA . registration . 1975 . New York . W. W. Norton and Company . 978-0-393-32044-2 .
  22. Book: Watson, James D. . The Double Helix: A Personal Account of the Discovery of the Structure of DNA . 1980 . 1980 Norton Critical . Gunther Stent . W. W. Norton and Company . 978-0-393-95075-5 . registration .
  23. Web site: NOVA: DNA – Secret of Photo 51 (2003). 26 January 2015. https://web.archive.org/web/20150204074312/http://www.nytimes.com/movies/movie/389902/NOVA-DNA-Secret-of-Photo-51/overview. 4 February 2015. Movies & TV Dept.. The New York Times. Nathan Southern. 2015. dead.
  24. Web site: Secret of Photo 51 Transcript. PBS. 26 January 2015. https://web.archive.org/web/20141231071217/http://www.pbs.org/wgbh/nova/transcripts/3009_photo51.html. 31 December 2014. live.
  25. Web site: Rosalind Franklin: DNA's Dark Lady (2003) (TV). MoviesPictures.ORG. 4 February 2015. https://web.archive.org/web/20150204065108/http://moviespictures.org/movie/Rosalind_Franklin_DNAs_Dark_Lady_2003_TV. 4 February 2015. dead.
  26. Web site: Season 1, Episode 1 The Secret of Life. TV Guide. 26 January 2015.
  27. Web site: Episode 1: The Secret of Life. PBS. 26 January 2015. https://web.archive.org/web/20141230115118/http://www.pbs.org/wnet/dna/episode1/. 30 December 2014. live.
  28. News: Cox. Gordon. Nicole Kidman to Star on West End in 'Photograph 51'. 25 August 2015. Variety. April 23, 2015. https://web.archive.org/web/20150908014035/http://variety.com/2015/legit/news/nicole-kidman-west-end-1201478267/. 8 September 2015. live.
  29. News: Ziegler's Photograph 51 Wins STAGE International Script Competition. 25 August 2015. American Theater Web News. August 5, 2008. https://web.archive.org/web/20150927154903/http://www.americantheaterweb.com/index.php/originals/2008/08/05/zieglers-ligphotograph-51l-ig-wins-stage. 2015-09-27. dead.
  30. Web site: Nicole Kidman Returns To The West End In Photograph 51 . Jacob . Porteous . London Theatre Direct . 24 April 2015 . 27 October 2015 . https://web.archive.org/web/20151016015641/https://www.londontheatredirect.com/news/1648/Nicole-Kidman-Returns-To-The-West-End-In-Photograph-51--Tickets-On-Sale-Now-.aspx . 16 October 2015 . live .
  31. https://genome.ch.bbc.co.uk/9820fc48eeb24a9b9e10ac42126e0d59