WATSON, CRICK, AND FRANKLIN STRUCTURE FOR DNA ROSALIND FRANKLIN, THE DOUBLE HELIX, AND THE TRUE GANGSTERS WATSON & CRICK Today is the 93th anniversary of Rosalind Elsie Franklin (25 July 1920 – 16 April 1958). Although she made essential contributions toward elucidating the structure of DNA, Rosalind Franklin is known to many only as seen through THE DISTORTING LENS OF JAMES WATSON’S BOOK, THE DOUBLE HELIX. The diffraction photograph of the B form of DNA taken by Rosalind Franklin in May 1952 was by far the best photograph of its kind. Data derived from this photograph were instrumental in allowing James Watson and Francis Crick to construct their Nobel Prize–winning model for DNA. FRUSTRATED CONTRIBUTORS TO DNA STRUCTURE : JERRY DONOHUE, the chemist who had insisted that James Watson try modeling DNA with the keto form of nitrogenous bases, expressed to historian Horace Judson his frustration at not being sufficiently acknowledged. “Let’s face it,” Donohue wrote, “if the fates hadn’t ordained that I share an office with Watson and [Francis] Crick in the Cavendish [Laboratory] in 1952–3, they’d still be puttering around trying to pair ‘like-with-like’ ENOL FORMS of the bases” (The original 5 March 1976 letter is in the Anne Sayre Collection of the Microbiological Society Archives at the University of Maryland, Baltimore County ; B. Maddox, Rosalind Franklin: The Dark Lady of DNA, HarperCollins, New York, 2002). ERWIN CHARGAFF similarly felt insufficiently acknowledged for discovering that the DNA bases GUANINE AND CYTOSINE (and likewise adenine and thymine) are present in approximately equal amounts. MAURICE WILKINS was frustrated because he, understandably, had expected to be collaborating with Watson and Crick. In 1951, Rosalind Franklin joined the Medical Research Council unit at King’s College, London. At that time, Wilkins lacked her years of experimental diffraction experience; like most of his MRC colleagues at the King’s biophysics unit, he was an accomplished scientist struggling to apply his prior experience in physics to biological problems. As a result, other MRC units jokingly called the biophysics unit “Randall’s Circus,” after director John Randall. WILKINS ACKNOWLEDGED THE NATURE OF RANDALL’S UNIT WHEN HE SAID OF FRANKLIN, “WE WERE AMATEURS, BUT SHE WAS A PROFESSIONAL.” Wilkins, though, learned quickly and acquired some valuable collaborators. By early 1953, approximately eight months after Franklin recorded her famous photograph #51, he and Herbert Wilson were able to use a variety of DNA sources to obtain x-ray photographs sufficiently detailed for structural studies (H. R. Wilson, Trends Biochem. Sci. 13, 275,1988). Later, Wilkins designed a higher-resolution x-ray camera that enabled his team to take diffraction photographs that helped to confirm and refine the Watson and Crick structure. Wilkins had initiated DNA structural studies at King’s and, in 1950 with Raymond Gosling, had taken the best DNA photograph to date—one that showed a high degree of crystallinity and thus implied that DNA structure could be solved by x-ray diffraction. Wilkins had recognized DNA’s genetic importance LONG BEFORE CRICK, obtained high-quality DNA from Rudolf Signer, and supported the hiring of experienced x-ray diffraction expert Rosalind Franklin. Wilkins is well respected by the King’s staff that I interviewed and his contributions were deemed worthy of a Nobel Prize. CONCLUSION Franklin is prominent in virtually every telling of DNA history, but she is painted differently in various accounts. Watson and Crick made one of the most important and impressive scientific discoveries of the 20th century, BUT THEIR GOLDEN HELIX IS TARNISHED BY THE WAY THEY HAVE TREATED ROSALIND FRANKLIN AND MAURICE WILKINS. A meaningful gesture, given that it was Franklin’s data that Watson and Crick most directly used, would be for scientists to refer to the “WATSON, CRICK, AND FRANKLIN STRUCTURE FOR DNA.” Read the notebook entry showing that Rosalind Franklin knew that most, if not all, of the nitrogenous bases in DNA were IN THE KETO CONFIGURATION (circles indicate the hydrogen positions that distinguish keto from enol form). The keto form of nitrogenous bases is basic in DNA. The enol and keto forms are said to be TAUTOMERS of each other. Note I have made biology-physics studies (see my article on «Ummo» in «Science & Inexpliqué» n°20, WHERE I GIVE THE EXACT UNFOLDED ATOMIC STRUCTURE OF THE KRYPTON, due to my sufficient knowledge of physics). Note the noun Ketone, chemical group (1851), FROM GERMAN KETON, COINED IN 1848 BY GERMAN CHEMIST LEOPOLD GMELIN (1788-1853) from German Aketon, from French acétone (see acetone). Its comb. form is keto-. Note, too, that THE ASTEROID 9241 Rosfranklin, discovered in 1997, was named in her honour. Logical, FOR ROSALIND WAS A TRUE ELF ! Other members of her family have died of cancer, and the incidence of gynaecological cancer is known to be disproportionately high among Ashkenazi Jews. etymonline/index.php?allowed_in_frame=0&search=ketone+body&searchmode=none https://en.wikipedia.org/wiki/Keto%E2%80%93enol_tautomerism scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PHTOAD000056000003000042000001&idtype=cvips&bypassSSO=1 en.wikipedia.org/wiki/Rosalind_Franklin en.wikipedia.org/wiki/9241_Rosfranklin
Posted on: Thu, 25 Jul 2013 16:47:42 +0000
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