Franklin, Rosalind Elsie

views updated May 17 2018

FRANKLIN, ROSALIND ELSIE

(b. London, United Kingdom, 25 July 1920; d. London, United Kingdom, 16 April 1958)

physical chemistry, x-ray crystallography. For the original article on Franklin see DSB, vol. 7.

Franklin was born in London on 25 July 1920, the second of five children of Ellis Franklin and Muriel Franklin, née Waley, both from families of high standing in Anglo-Jewry. The Franklins came as Fraenkels to London from Breslau, Silesia, in 1763 and became wealthy bankers. By 1868 their financial base was a merchant bank, Keysers, which provided employment for many Franklin sons. Her novel position as an upper-class Englishwoman and a Jew shaped Rosalind Franklin’s life.

Early Years . Franklin was educated in London at the academically distinguished London day school, St. Paul’s Girls’, where girls were encouraged to prepare for a career. Rosalind decided to specialize in science, one of her best subjects. Her family was startled because Franklin women were not expected to take paid employment. In 1938 she went to Newnham College, a women’s college collect at Cambridge University. After receiving a good second-class degree in physical chemistry, she chose war-related work for the British Coal Utilisation Research Board. Her published work on the structure of coals and carbons gave her an international reputation. In 1945 she received her doctorate from Cambridge with a thesis titled “The Physical Chemistry of Solid Organic Colloids with Special Reference to Coal and Related Materials.”

From 1947 until the end of 1950, Franklin worked in Paris at the Laboratoire central des services chimiques de l’état, becoming skilled at the x-ray diffraction of disordered crystalline material such as coal. At the end of 1950, at the age of thirty, she accepted an appointment at King’s College London (KCL), associated with the University of London. On 4 December 1950, John Turton Randall, head of biophysics at KCL, wrote her a letter that changed completely the direction of her planned research. Randall said it now seemed more important for her “to investigate the structure of certain biological fibers in which we are interested. This means that as far as the experimental x-ray effort is concerned there will be at the moment only yourself and [graduate student Raymond] Gosling” (Olby, 1974, p. 346).

Randall did not explain that Dr. Maurice Wilkins, his deputy, had published important papers on the deoxyribonucleic acid, DNA, and considered the DNA project “his.” As Randall never showed Wilkins his letter, Wilkins thought that Franklin was coming to join his team. Yet Franklin sensed trouble. From Paris she wrote in a letter to her brother, “I far prefer here the place, the people, the life and the climate. I feel—and felt even before I came to France—far more European than English” (Maddox, 2002, p. 115).

In fact, however, returning to England was a good career move, taking Franklin into the new hybrid field of biophysics, where Britain was far more advanced than France. However, when Franklin arrived at KCL in January 1951 she hated it instantly. In the London of King George VI, Franklin’s quick, clipped voice carried a class label. According to Dr. Jean Hanson, the senior biologist at King’s College’s Biophysics Unit, “Just the way she spoke … there were people at that time who sneered at the upper-class way of speaking, and really hated it” (Maddox, 2002, p. 127). More alienating for Franklin was King’s College’s ecclesiastical atmosphere. Theology was its biggest department, with four hundred students training for the Anglican priesthood. When she was informed that women were not allowed in the college’s senior common room, where some of the staff ate lunch, she was angry. As she wrote to her American friend, Anne Sayre, on 1 March 1952, “King’s has neither foreigners nor Jews” (Maddox, 2002, p. 172). She was wrong, but her words show that she felt like an outsider.

DNA Crystallography . Franklin’s work went well. In making x-ray photographs of crystalline fibers of DNA, she was assisted by her graduate student, the amiable Raymond Gosling, and by the excellent samples of DNA fibers prepared by Professor Rudolf Signer of the University of Berne, in Switzerland, which were obtained for King’s College by Wilkins, who was away when she arrived. The only researcher working at high humidity, she took sharp, clear pictures that revealed two forms of DNA. When hydrated to absorb water, the fiber became longer and thinner. When placed over a drying agent, it changed back. This transformation explained why earlier attempts—made by Wilkins, among others—to understand DNA’s structure had been unsuccessful, as they had been looking at a blur of the two forms.

Franklin and Gosling called the longer, heavily hydrated DNA the “B” form; they called the other, shorter and drier, the “A” form. This discovery was indebted to Franklin’s expertise, for she had ordered special equipment from Paris, designed a tilting camera, pulled exceptionally thin DNA fibers, and perfected her technique for orienting the fibers in front of the camera’s beam.

Franklin did not share her findings with Wilkins because she was shocked by his ignorance of what she felt were simple hydration techniques. Trouble between them began in the summer of 1951. When he offered an adverse opinion on some of her results, she was outraged.

This was the type of dispute some could settle over a drink at the pub. But Franklin and Wilkins were temperamental opposites, she quick speaking and combative; he shy, tentative, and evasive. He thought she had been brought in to help his team with x-ray crystallography. She thought she had the x-ray work to herself. Finally, Randall intervened and gave Franklin all the Signer DNA and told her to concentrate on the A form.

Consequently, Wilkins felt shut out of his own project. On frequent visits to Cambridge, he talked with his old friend, Francis Crick, at the Cavendish Laboratory. Crick, although working on horse hemoglobin, was interested in DNA. So was the American, James Watson, who heard Wilkins pour out his troubles with “Rosie.” In November 1951, after Watson had heard Franklin describe her work at a King’s College seminar, he and Crick constructed a model of a possible structure for DNA. When Franklin and others from King’s came to inspect it, they knew at a glance that it was wrong. Embarrassed, Sir Lawrence Bragg, head of the Cavendish Laboratory, which was not supposed to be working on DNA, ordered Watson and Crick to drop it immediately.

Continuing her systematic x-ray investigation of the Signer DNA fibers, Franklin calculated the dimensions of the unit cell of the molecule and the location of its phosphates—on the outside. In early 1952 she reported that her evidence suggested “a helical structure (which must be very closely packed) containing probably 2, 3 or 4 co-axial nucleic acid chains per helical unit” (Report to Turner-Newall, in Franklin Archives).

Over 1 and 2 May 1952, Franklin and Gosling got an exceptionally clear picture of the B form of DNA, showing a stark “X” that suggested a helix. She worked out the distance between turns of the helix and the number of base pairs within it. Numbering the photograph 51, she put it aside, to return (as agreed with Randall) to the A form.

In mid-December 1952 the unpublished results of her x-ray work were included in a report prepared for the visiting biophysics committee of the Medical Research Council (MRC), the government agency financing both

Randall’s research unit at King’s and Bragg’s at the Cavendish Laboratory. Franklin’s summary gave the full dimensions of the DNA unit cell, its density, and her claim to have established “with certainty” that the crystal fell into the C2 space group that crystallogrphers call “face-centered monoclinic.”

Move to Birbeck . In January 1953 Franklin announced that she was leaving KCL in March, having negotiated the transfer of her Turner and Newall Fellowship to Birkbeck College, a secular institution within the University of London. She was giving up DNA work for as-yet-unspecified research. “I may be moving from a palace to the slums,” she wrote to a friend on 10 March 1953, “but I’m sure I will be happier” (Maddox, 2002, p. 205). Her new boss, J. Desmond Bernal, a well-known physicist and a Communist, was a brilliant crystallographer.

At King’s College, Ray Gosling, about to lose Franklin as his thesis adviser, gave the photographs he and Franklin had taken to Maurice Wilkins. On 30 January 1953, Watson came into Franklin’s room at King’s and offered to show her the pre-publication paper of Linus Pauling of the California Institute of Technology in Pasadena, claiming to have solved the structure of DNA. The paper, given to Watson by Pauling’s son Peter, showed that Pauling had made a fundamental chemical mistake in placing the phosphates in the center where they could not be ionized. He also proposed a triple-strand helix.

Franklin countered with her own evidence against a helical structure. Watson then went into Wilkins’s lab where Wilkins, defending the helical theory, showed Watson Photo 51 of Franklin and Gosling. One look told Watson that the DNA molecule has the form of a helix. He then persuaded Crick to try another model.

At the Cavendish Laboratory, Watson and Crick asked their colleague, Max Perutz, a member of the MRC’s biophysics committee, to show them a copy of the MRC report. When Crick saw Franklin’s evidence that the molecule belonged to the “monoclinic C2” space group, he knew instantly that the DNA’s two chains of nucleic acid must be anti-parallel.

Then Watson spotted that the two chains of DNA were linked by pairs of bases that always occurred in the same combinations. When the chains came apart, these bases would seek each other out and, therefore, copy themselves. By the end of February 1953 Watson and Crick had completed their now-celebrated model, with its twisting coils of paired atoms.

Meanwhile, Franklin’s notebooks show that at the end of February 1953, she took out Photo 51 and concluded that both the A and the B forms of DNA were two-chain helices. Her work was ready for publication just as Crick and Watson began trying to publish their discovery quickly, and to find a way to acknowledge the embarrassing fact that all the experimental work behind it had been done at King’s College. Wilkins got Watson and Crick to agree that there should be a second paper in Nature, written by himself (Wilkins), Alec Stokes, and Herbert Wilson, describing the DNA research of the three of them. Wilkins then learned that Franklin and Gosling had finished writing their own paper.

On 17 March 1953 Franklin adapted this paper in order for it to accompany the Watson-Crick paper, making three papers in Nature. She inserted the words, “Thus our general ideas are consistent with the model proposed by Crick and Watson.” So they should have been added, as the Watson-Crick model was in large part derived from her work. Photo 51 of the B form of DNA appeared as an illustration to the Franklin-Gosling paper, “Molecular Configuration in Sodium Thymonucleate,” published in Nature on 25 April 1953, with no suggestion that Watson had seen it.

Franklin had no sense of having been exploited. Nor did she accept Watson and Crick’s ideas as more than a hypothesis. In the second of her two papers that appeared in Acta Crystallographica in September 1953, she wrote of “the Watson-Crick model” that “discrepancies prevent us from accepting it in detail” (Maddox, 2002, p. 223).

Work on TMV . At Birkbeck College, Franklin formed her own team of dedicated disciples (including the subsequent Nobel laureate, Sir Aaron Klug) and published seventeen papers on the tobacco mosaic virus, TMV.

Starting in 1954, Franklin’s earlier carbon work brought her several welcome invitations to conferences in the United States. In August 1956 she was diagnosed in London with ovarian cancer. She died in April 1958. That year Bernal wrote of her in Nature that “her photographs are among the most beautiful x-ray photographs of any substance ever taken” (1958, p. 154). In 1962 Watson, Crick, and Wilkins got the Nobel Prize. Only Wilkins mentioned, very briefly, Franklin’s part.

Franklin had come very close to getting the answer to the structure of DNA. That her draft manuscript of 17 March 1953, proving how close she was, should not have come to light until many years later—reported in an article, “Corrigendum,” by Klug, for Nature (1968)—is one of the many ways in which fortune did her no favors. In the late twentieth and early twenty-first centuries she became an icon of the oppressed female scientist. Ironically, posterity would not have known of her part in discovering DNA’s structure had Watson not revealed it, however unflatteringly, in his 1968 book, The Double Helix.

SUPPLEMENTARY BIBLIOGRAPHY

Rosalind Franklin’s papers are held in the Churchill College Archives, Cambridge University, England.

WORKS BY FRANKLIN

“The Physical Chemistry of Solid Organic Colloids with Special Reference to Coal and Related Materials.” PhD diss., Cambridge University, Cambridge, UK, 1945.

“A Note on the True Density, Chemical Composition, and Structure of Coals and Carbonized Coals.” Fuel 27 (1948): 46–49.

“Influence of the Bonding Electrons on the Scattering of X-Rays by Carbon.” Nature 165 (14 January 1950): 71–72.

“Crystallite Growth in Graphitizing and Non-graphitizing Carbons.” Proceedings of the Royal Society 209 (1951): 196–218.

With R. G. Gosling. “Molecular Configuration in Sodium Thymonucleate.” Nature 171 (25 April 1953): 740–741.

With R. G. Gosling. “Evidence for 2-Chain Helix in Crystalline Structure of Sodium Deoxyribonucleate.” Nature 172 (25 July 1953): 156–157.

With R. G. Gosling. “The Structure of Sodium Thymonucleates Fibres. I. The Influence of Water Content.” Acta Crystallographica 6 (10 September 1953): 673–677.

With R. G. Gosling. “The Structure of Sodium Thymonucleate Fibres. II. The Cylindrically Symmetrical Patterson Function.” Acta Crystallographica 6 (10 September 1953): 678–685.

“Structure of Tobacco Mosaic Virus.” Nature 175 (26 February 1955): 379–381.

With K. C. Holmes. “The Helical Arrangement of the Protein Sub-units in Tobacco Mosaic Virus.” Biochimica et Biophysica Acta 21 (1956): 405–406.

With A. Klug. “The Nature of the Helical Groove on the Tobacco Mosaic Virus Particle.” Biochimica et Biophysica Acta 19 (1956): 403–416.

“Location of the Ribonucleic Acid in the Tobacco Mosaic Virus Particle.” Nature 177 (1956): 928–930.

With A. Klug and J. T. Finch. “Structure of Turnip Yellow Mosaic Virus: X-ray Diffraction Studies.” Biochimica et Biophysica Acta 25 (1957): 242–252.

With A. Klug, J. T. Finch, and K. C. Holmes. “On the Structure of Some Ribonucleoprotein Particles.” Transactions of the Faraday Society 25 (1958): 197–198.

With A. Klug. “Order-disorder Transitions in the Structures Containing Helical Molecules.” Discussions of the Faraday Society 25 (1958): 104–110.

With K. C. Holmes. “The Radial Density Distribution in Some Strains of Tobacco Mosaic Virus.” Virology 6 (1958): 328–336.

With A. Klug. “The Structure of RNA in Tobacco Mosaic Virus and in Some Other Ribonucleoproteins.” Transactions of the Faraday Society 55 (1959): 494–495.

OTHER SOURCES

Bernal, J. D. “Dr. Rosalind E. Franklin.” Nature 182 (19 July 1958): 154.

Elkin, Lynne Osman. “Rosalind Franklin and the Double Helix.” Physics Today 56 (March 2003): 42–48.

Franklin, Arthur E. Records of the Franklin Family and Collaterals. 2nd ed. London: Routledge, 1935.

Glassman, Gary. The Secret of Photo 51. WGBH-Noval, PBS. 22 April 2003.

Glynn, Jenifer. “Rosalind Franklin 1920–1958.” In Cambridge Women: Twelve Portraits, edited by Edward Shils and Carmen Blacker. Cambridge, UK: Cambridge University Press, 1996.

Harris, Peter. “On Charcoal.” Interdisciplinary Science Reviews 24 (1999): 301–306.

———. “Rosalind Franklin’s Work on Coal, Carbon, and Graphite.” Interdisciplinary Science Reviews 26 (2001): 204–209.

Hubbard, Ruth. “The Double Helix: A Study of Science in Context.” In The Politics of Women’s Biology. New Brunswick, NJ, and London: Rutgers University Press, 1990.

Klug, Aaron. “Rosalind Franklin and the Discovery of the Structure of DNA.” Nature 219 (24 August 1968): 808–810, 843–844, 879–880.

———. “Corrigendum.” Nature 219 (14 September 1968): 1192.

———. “Rosalind Franklin and the Double Helix.” Nature 248 (26 April 1974): 787–788.

———. “The Tobacco Mosaic Virus Particle: Structure and Assembly.” Philosophical Transactions: Biological Sciences 354 (29 March 1999): 531–535.

Maddox, Brenda. Rosalind Franklin: The Dark Lady of DNA. New York: HarperCollins, 2002.

Nicholson, W. Life Story. BBC2 Horizon Programme. 27 April 1987.

Olby, Robert. The Path to the Double Helix. London: Macmillan, 1974.

Sayre, Anne. Rosalind Franklin and DNA . New York: Norton, 1975.

Watson, James D. The Double Helix: A Personal Account of the Discovery of the Structure of DNA. New York: Atheneum, 1968.

Wilkins, Maurice. The Third Man of the Double Helix: The Autobiography of Maurice Wilkins. Oxford: Oxford University Press, 2003.

Brenda Maddox

Franklin, Rosalind Elsie

views updated May 18 2018

Franklin, Rosalind Elsie

(b. London, England, 25 July 1920; d. London, 16 April 1958)

physical chemistry, molecular biology.

The daughter of a banking and artistic family previously unconnected with sciences, Rosalind Franklin was a foundation scholar at St. Paul’s Girls’s School, London, from which she won an exhibition to Newnham College, Cambridge, in 1938. After graduating in 1941 she stayed on to investigate gas-phase chromatography under Ronald Norrish. In 1942 she joined the British Coal Utilisation Research Association where, under D. H. Bangham, she applied her expertise in physical chemistry to the problem of the physical structure of coals and carbonized coals. From 1947 to 1950 Franklin worked under Jacques Méring at the Laboratoire Central des Services Chimiques de l’État, Paris, where she developed her skill in X-ray diffraction techniques and applied them to a detailed and illuminating study of carbons and of the structural changes accompanying graphitization. In 1951 she joined Sir John Randall’s Medical Research Council unit at King’s College, London, to apply these techniques to the problems of the structure of DNA, and in 1953 she moved to Birkbeck College, London, to work similarly on the even more exacting problems of virus structure.

At the British Coal Utilisation Research Association, Franklin developed, with Bangham and other workers, a hypothesis of the micellar organization of coals which provided a satisfactory explanation of their absorptive behavior toward liquids and gases and their thermal expansion. From her study of the fine porosity of a range of coals, by measurements of true and apparent densities, Franklin concluded that their structure was best represented by a model with pore constrictions which gave coals the properties of molecular sieves. In Paris she turned her attention to the application of X-ray diffraction methods to the problems of carbon structure and developed a procedure for the detailed interpretation of the diffuse X-ray diagram of carbons. This allowed her to describe the structure in more precise quantitative terms than had been possible, and she made use of it to study in detail the structural changes that accompanied the formation of graphite when these carbons were heated to high temperatures.

In the course of this work Franklin developed a relation between the apparent interlayer spacing of the partially graphitized carbons and the proportion of disoriented layers, which has proved of considerable value in the industrial study of carbons. In addition, by studying the changes in structure that chars of different origin underwent on heating, she established that there are two distinct classes of carbons—those which form graphite on heating to high temperatures (the graphitizing carbons) and those which do not (the nongraphitizing carbons)— and related these differences in behavior to structural differences in the parent chars. She showed, in particular, that the graphitizability increases with the finestructure porosity and this, in turn, she believed to be related to the cross-linking between the crystallites.

Franklin’s work on coals brought her into contact with Charles Coulson, through whom she was introduced to Randall, and with the award of a Turner Newall Fellowship she went to work in the King’s College Medical Research Council Biophysics Unit. At that time (January 1951) Raymond Gosling, under M. H. F. Wilkins’ direction, had obtained diffraction pictures of DNA showing a high degree of crystallinity; sharper pictures were obtained with higher ambient humidity.

Franklin and Gosling conducted a systematic study of the effect of humidity on the X-ray pattern produced. Using salt solutions to control humidity, they showed that there are two distinct intramolecular patterns, which they found to be producible from the same specimen: the crystalline “A” pattern at 75 percent relative humidity and a new “Wet” paracrystalline pattern at 95 percent relative humidity. In a report which Franklin gave on this work in November 1951, she described this discovery and went on to show, as Wilkins had a year before in Cambridge, that the patterns were consistent with a helical conformation. She discussed how the A ⇋B transformation takes place and suggested, quite correctly, that the phosphates are on the outside of the helices and in the “A” form are held parallel to each other by electrostatic attraction between O- and Na+. When water is added, it penetrates between the helices, thus destroying the electrostatic attraction which holds them in parallel alignment. She said little about the forces operating inside the helices but mentioned hydrogen bonding between keto and amino groups of the bases.

Despite this promising beginning Franklin was too professional a crystallographer to proceed further in this way. Instead, she thought to solve the structure of DNA in an inductive manner by using Patterson functions and superposition. While publicly she heaped scorn on those who were convinced that DNA is helical, in her unpublished reports she stated that such a conformation is probable for the B form and not inconsistent with the A form. A spurious case of double orientation encountered in April 1952, which when indexed showed marked radial asymmetry (all left-hand reflections were indexed hKL and all righthand ones hkl̄), led her to seek nonhelical structures for the A form. Earlier ambiguities in the indexing of the A diagram had led Franklin to embark on a Patterson analysis. This helped her to obtain accurate parameters for the unit cell. Yet the cylindrical Patterson function obtained by Gosling in July 1952 strengthened her antihelical views, although the arrangement of peaks was consistent with a helix. She was misled, by what appeared to be clear evidence of a structural repeat at half the height of the unit cell, into ruling out helices for the A form, since no DNA chain could possibly be folded into a helix with a pitch equal to half the height of the unit cell (fourteen Å.)

At this time Franklin was thinking in terms of antiparallel rods in pairs back-to-back, forming a double sheet structure. Then she investigated diagonal rod structures such as would simulate the diffraction pattern of a helix, but by January 1953, when she started model building, she found such structures impossible to build. Still rejecting single- or multistrand helices, she investigated a figure-eight structure in which a single chain formed a long column of repeating eights. This, she believed, would account for the halving of the unit cell in the cylindrical Patterson function and clearly provided a form of tight packing which could be unfolded to give the dramatic increase in length (30 percent) when structure A changes to structure B. She knew that the helix in the extended B form is close-packed and was doubtful that the same type of structure could pack down even more densely.

At the end of February 1953 Franklin turned to the B Pattern, and for two weeks she weighed the merits of single and multiple helices. In a paper dated 17 March which she wrote with Gosling, she ruled out triple-strand and equally spaced double-strand helices and stated that “if there are two nonequivalent, i.e., unequally spaced coaxial chains these are separated by 3/8th. of the fibre axis period.” This is the conformation of the sugar-phosphate backbones as found in the Watson-Crick model. On the following day Franklin returned to the Patterson function of the A form, only to learn that Watson and Crick had solved the structure of the B form. She and Gosling quickly expanded and rearranged their draft paper of 17 March in the light of the Cambridge discovery so that it could appear in the 25 April issue of Nature, which contains Watson and Crick’s paper on their model.

Franklin deserves credit for having discovered the A ⇋B transformation and characterized the diffraction patterns of these forms of DNA; for providing Watson and Crick with vital data, in particular the parameters of the unit cell; for exposing the errors in their first unpublished model; and for marshaling the evidence in favor of the phosphates being on the outside of the helix. It was also she who, with the aid of the special tilting camera built by Gosling, discovered the meridional reflection on the eleventh layer line in the A pattern and was the first to show how the B form can pack down more tightly to give the A form with eleven residues in one turn of the helix. Although she had been misled by the cylindrical Patterson function, this did provide the most refined evidence in favor of the Watson-Crick model at the time of its discovery in 1953. Franklin and Gosling’s rarely cited paper on this subject appeared in Nature on 25 July 1953.

For the last five years of her life Franklin worked in the Crystallography Laboratory of Birkbeck College, London, supported first by the Agricultural Research Council and later by the U.S. Department of Health. There she continued to publish on her earlier work on coals, completed the writing up of her DNA work, and took up the structure of tobacco mosaic virus (TMV). By 1956 she had greatly improved on J. D. Watson’s X-ray pictures of 1954. With the aid of material supplied by Heinz Fraenkel-Conrat and by Gerhard Schramm, Franklin and her co-workers, A. Klug and K. C. Holmes, were able to reject the picture of TMV as a solid cylinder with the RNA in the center and the protein subunits, possibly of two types, on the outside. They showed that the particles are hollow, that the protein subunits are structurally of one type only, and that forty-nine such units are packed in helical array around the axis in the axial repeat period of sixty-nine Å. The greatest achievement of the Franklin team was the location of the RNA helix embedded within the protein fraction at a radial distance of forty Å. from the axis. From a study of the X-ray diagram of TMV, Franklin and Klug resolved the discrepancy between estimates of the maximum radius and the packing radius by postulating the morphology of the protein as “a helical array of knobs, one knob for each sub-unit.” Shortly before her death from cancer, Franklin instituted work which was later to justify her conclusion that the RNA in TMV is present in the form of a single-strand helix.

Franklin was a deft experimentalist, keenly observant and with immense capacity for taking pains. As a result she was able with difficult material to achieve a remarkable standard of resolution in her X-ray diagrams. Although a bold experimentalist, she was critical of speculation, favoring an inductive approach which proved very successful in her work on coals and TMV but which allowed others to get ahead of her in her work on DNA. Where those with a more intuitive approach rejected antihelical data as spurious, Franklin felt obliged to invent other conformations which might yield a helical-type pattern. She would not trust to the principle of exclusion, nor was she confident of the “Obvious” deductions dictated by physical intuition. Hence her work was not marked by great originality of thought. Her theory of graphitization, for instance, although the best of its day, was traditional in character and belongs to what is now regarded as the “Classical” period. Her great strength lay in her technical innovations and her employment of precise technique on difficult macromolecules. When she died at the age of thirty-seven, she had won international recognition both as an industrial chemist and as a molecular biologist.

BIBLIOGRAPHY

I. Original Works. Franklin and her co-workers published about forty papers. A complete list of her publications on the structure of viruses is in her paper written with D. L. D. Casper and A. Klug, “The Structure of Viruses as Determined by X-Ray Diffraction,” in C. S. Holton et al., eds., Plant Pathology: problems and progress, 1908–1958 (Madison, Wis., 1959), pp.447–461. This paper provides a broad review of Franklin’s work and contains a tribute to her by W. M. Stanley.

Of her other papers the following appeared in Acta crystallographica: “The Interpretation of Diffuse X-Ray Diagrams of Carbon,” 3 (1950), 107–117; “A Rapid Approximate Method for Correcting Low-Angle Scattering Measurements for the Influence of the Finite Height of the X-Ray Beam,” ibid., 158–159; “The Structure of Graphitic Carbons,” 4 (1951), 253–261; “The a Dimension of Graphite,” ibid., 561; and “The structure of Sodium Thymonucleate Fibres. I, II, & III,” 6 (1953), 673–677, 678–685; 8 (1955), 151–156.

Other important papers are “A Note on the True Density, Chemical Composition and Structure of Coals and Carbonized Coals,” in Fuel, 27 (1948), 46–49; “A Study of the Fine-Structure of Carbonaceous Solids by Measurements of True and Apparent Densities. Part I. Coals. Part II. Carbonized Coals,” in Transactions of the Faraday Society, 45 (1949), 274–286, 668–682; “Crystallite Growth in Graphitizing and Nongraphitizing Carbons,” in Proceedings of the Royal Society, 209A (1951), 196–218; “Molecular Configuration in Sodium Thymonucleate,” in Nature, 171 (1953), 740–741; and “Evidence for 2-Chain Helix in Crystalline Structure of Sodium Deoxyribonucleate,” ibid., 172 (1953), 156–157.

Her last paper, written with A. Klug, was published after her death: “Order-Disorder Transitions in Structures Containing Helical Molecules,” in Discussions of the Faraday Society, 25 (1958), 104–110.

II. Secondary Ltterature. Obituary notices appeared in The Times (19 Apr. 1958), p.3; and Nature, 182 (1958), 154.

For two very different accounts of Franklin’s work on DNA, see J. D. Watson, The Double Helix (New York, 1968), Passim; and A. Klug, “Rosalind Franklin and the Discovery of the Structure of DNA,” in Nature, 219 (1968), 808–810, 843–844; corrigenda, 879, 1192; correspondence, 880.

Robert Olby

Franklin, Rosalind

views updated May 29 2018

Franklin, Rosalind


ENGLISH MOLECULAR BIOLOGIST
19201958

Rosalind Elsie Franklin, the second of four children and the first daughter of Ellis Franklin, a wealthy Jewish banker, and Muriel Franklin (née Waley), was born on July 25, 1920, in London. Although raised in a happy home where children were encouraged to develop their individuality, Rosalind felt discriminated against because she was a girl, a feeling that surfaced again, along with an awareness of anti-Semitism, when she was working on DNA at King's College.

In 1938 Franklin graduated from St. Paul's Girls' School in London, where, at age fifteen, she decided to become a scientist. Although her father disapproved of college education for women, she attended Newnham College, a women's college at Cambridge University, from which she received a bachelor's degree in 1941. She spent a year (19411942) working with future (1967) Nobel chemistry laureate Ronald George Wreyford Norrish, after which she contributed to the World War II effort by working as a physical chemist for the British Coal Utilization Research Association (19421945). Her research on the structural changes caused by heating coal resulted in five publications, earned her a doctorate, and made her a recognized authority on crystallography and industrial chemistry.

Franklin's next three years (19471950) were spent as a research scientist at the Laboratoire Central des Services Chimiques de l'État in Paris. She became a researcher at King's College, London, in 1951, where she began to work on the structure of deoxyribonucleic acid (DNA), the physical basis of heredity. Her relationship with DNA coworker Maurice Hugh Frederick Wilkins (b. 1916), a biophysicist from New Zealand, soon degenerated into one of mutual dislike. In England two laboratories were working on the crystalline structures of biological materials: King's College was working on DNA, and the Cavendish Laboratory in Cambridge was working on proteins. The American James Dewey Watson (b. 1928) and the Briton Francis Harry Compton Crick (b. 1916) decided that DNA research was more exciting than the protein research in which they were thought to be engaging at the Cavendish.

Franklin discovered that DNA occurs in two forms (the "A" form, which is more crystalline, contains more water than the "B" form, which is the form that occurs in cells). When Watson and Crick visited King's, Wilkins showed them Franklin's x-ray diffraction photographs of the "B" structure. Her critique of Watson and Crick's earlier work helped them reformulate their structure. However, she failed to recognize the significance of the particular crystal symmetry system (monoclinic C2 symmetry) of "B" DNA. Crick, who was working on hemoglobin, which possessed C2 symmetry, recognized that this meant that the strands of nucleic acid are antiparallel, so they could serve as templates for each other. This insight, together with Watson's knowledge of Erwin Chargaff's base pairing, led to their final success. Watson, Crick, and Wilkins received the Nobel Prize in physiology or medicine in 1962.

Watson and Crick wished to publish quickly, before Linus Pauling, but were embarrassed that all the experimental work had been performed at King's, and Franklin's data had not been published. The heads of King's and the Cavendish approached the editors of Nature, who agreed to publish three articles in a single issue (April 25, 1953).

Watson and Crick's short paper was followed by an analysis by Wilkins, A. R. Stokes, and H. R. Wilson of the x-ray crystallographic data and Franklin and her graduate student Raymond G. Gosling's conclusion that the phosphate backbone of DNA lies on the outside of the structure. The Watson and Crick paper provided the experimental evidence for the helical structure of nucleic acids. Actually, Franklin and Gosling's paper provided the basis for Watson and Crick's structure, rather than being a confirmation of it.

Because Franklin and Wilkins were hardly speaking to each other, Franklin left King's College in 1953 for Birkbeck College, also in London, where she finished her DNA work and became head of the team studying tobacco mosaic virus. Franklin died of ovarian cancer on April 16, 1958, at the age of 37.

see also Deoxyribonucleic Acid (DNA); Double Helix; Pauling, Linus; Watson, James Dewey.

George B. Kauffman

Bibliography

Chemistry & Industry (2003). "Rosalind Franklin: The Woman behind the DNA Helix" Chemistry & Industry 8 (April 21):13.

Elkin, Lynne Osman (2003). "Rosalind Franklin and the Double Helix." Physics Today 56 (March):42.

Harvey, Joy, and Ogilvie, Marilyn B. (2000). "Rosalind Elsie Franklin (19201958)." In The Biographical Dictionary of Women in Science: Pioneering Lives from Ancient Times to the Mid-20th Century, Vol. 1, ed. Marilyn Ogilvie and Joy Harvey. New York and London: Routledge.

Julian, M. M. (1983). "Rosalind Franklin, from Coal to DNA to Plant Viruses." Journal of Chemical Education 60:660662.

Klug, Aaron (1968). "Rosalind Franklin and the Discovery of the Structure of DNA." Nature 219:808810, 843844.

Maddox, Brenda (2002). Rosalind Franklin: The Dark Lady of DNA. New York: Harper Collins Publishers.

McGrayne, Sharon Bertsch (1998). Nobel Prize Women in Science: Their Lives, Struggles, and Momentous Discoveries, 2nd edition. Washington, DC: Joseph Henry Press.

Miksic, Mary Clarke (1993). "Rosalind Elsie Franklin (19201958)." In Women in Chemistry and Physics: A Biobibliographic Sourcebook, ed. Louise S. Grinstein, Rose K. Rose, and Miriam Rafailovich. Westport, CT, and London: Greenwood Press.

Olby, Robert (1972). "Rosalind Elsie Franklin (19201958)." In Dictionary of Scientific Biography, Vol. 5, ed. Charles Coulston Gillispie. New York: Scribner.

Rayner-Canham, Marelene, and Rayner-Canham, Geoffrey (1998). Women in Chemistry: Their Changing Roles from Alchemical Times to the Mid-Twentieth Century. Washington, DC: American Chemical Society.

Sayre, Anne (1975). Rosalind Franklin and DNA. New York: W.W. Norton & Co.

Watson, James D. (1968). The Double Helix: A Personal Account of the Discovery of DNA. New York: Atheneum.

Internet Resources

Franklin, Rosalind, and Gosling, Raymond G. (1953). "Molecular Configuration in Sodium Thymonucleate." Nature 171:740741. Available from <http://www.nature.com/nature/dna50/franklingosling.pdf>.

"NOVA: Secret of Photo -51." PBS Online. Available from <http://www.pbs.org/wgbh/nova/photo51>.

Rosalind Elsie Franklin

views updated Jun 08 2018

Rosalind Elsie Franklin

The British physical chemist and molecular biologist Rosalind Elsie Franklin (1920-1958) made her most outstanding contribution to molecular biology by establishing the crystallographic basis for the structure of DNA.

Rosalind Elsie Franklin was born in London, England, on July 25, 1920, the second child and first daughter of Ellis and Muriel (Waley) Franklin. Her family's background was in banking and the arts. Yet, by the age of 15 she had chosen science as her vocation. Years later she still debated this decision with her father, who eventually accepted it even though it meant, at that time, a choice of career over marriage and family life.

Following St. Paul's Girls' School in London, she went to Cambridge University in 1938 as a chemistry student at Newnham College. After graduation in 1941 she remained in Cambridge on a research scholarship to study gas-phase chromatography with Ronald G. W. Norrish, a Nobel Laureate for Chemistry in 1967.

Between 1942 and 1946 Franklin's expertise in physical chemistry was called upon to study the physical structure of coals as assistant research officer of the British Coal Utilization Research Association. In 1945 Franklin received her Ph.D. from Cambridge University for a thesis on "The Physical Chemistry of Solid Organic Colloids with Special Relation to Coal and Related Materials."

Early in 1947 Franklin left London for Paris where she was a researcher at the Laboratoire Central des Services Chimiques de l'État. There she worked closely with Jacques Méring until the end of 1950, having become an expert in X-ray crystallography. Her work was fundamental for what is now known as carbon-fiber technology.

As X-ray crystallography of biological compounds was rapidly expanding in Britain under the auspices of the Medical Research Council (MRC) in the early 1950s, Franklin returned to London. She joined the MRC Unit at King's College. There John Randall, who arranged for her to receive the Turner-Newall fellowship for three years, suggested that she work on DNA (deoxyribonucleic acid) structure.

The main outcome of the research Franklin conducted at King's College between January 1951 and March 1953 was published, with her research student Raymond G. Gosling as a co-author, in Nature on April 25, 1953. It included the X-ray photography of the B form of DNA ("Sodium deoxyribose nucleate from calf thymus. Structure B"), which provided the basis for the interpretation of DNA structure as a double helix by James D. Watson and Francis H. C. Crick. Their own famous paper appeared in the same issue also, in the section "Molecular Structure of Nucleic Acids." This joint publication, accompanied by yet another corroborating paper on DNA structure by Maurice H. F. Wilkins, A. R. Stokes and H. R. Wilson, also from King's College, conveys a misleading impression of the circumstances of the discovery of DNA structure. It appears as if this discovery resulted from a close cooperation linking the MRC Biophysics Research Unit and the Wheatstone Physics Laboratory, King's College, in London, and the MRC Unit for the Study of the Molecular Structure of Biological Systems at the Cavendish Laboratory in Cambridge, where Watson and Crick worked. Due to this contiguity, the experimental papers by Franklin and Gosling and by Wilkins, Stokes, and Wilson became "mere" corroborations, although they were independent interpretative efforts. In contrast, the double helix model gained further credibility from this juxtaposition, as it moved from the status of a "hypothesis" to that of a "proven" theoretical statement. All three papers professed advance knowledge of the general nature of the research performed both in King's College and in Cambridge.

By the time her DNA paper was published Franklin was no longer at King's College. She had found it imperative to leave because of Randall's unjustifiable injunction to abandon the DNA problem altogether. She moved to Birkbeck College in London, where John Desmond Bernal (1901-1971), a founder of British X-ray crystallography of biological compounds, welcomed her to work on the structure of TMV (tobacco mosaic virus), a project he had begun before World War II. In 1954 Franklin and Aaron Klug started a fruitful collaboration. Following her untimely death in 1958 he brought to completion their TMV work. He was awarded the Nobel Prize for Chemistry in 1982, in part for this work.

With the recognition of the fundamental importance of DNA structure for molecular biology in the 1960s, Franklin's work on DNA became a subject of great attention. In 1962 the Nobel Prize for Medicine or Physiology was awarded to Crick, Watson, and Wilkins, when Franklin was no longer alive. First clues about her role in the complex events which surrounded the discovery of DNA structure emerged in 1968 when Watson published his bestselling and highly controversial autobiography, The Double Helix. Nicknamed "Rosy" in a derogatory manner, Franklin was depicted there as the key obstacle to Watson and Crick's hunt for a helical interpretation of DNA. She was allegedly "anti-helical" and refused to disclose data she was in the course of interpreting herself. Franklin, Wilkins, and Linus C. Pauling, the Nobel Laureate for Chemistry (1954) and for Peace (1962) who had worked briefly on DNA in 1953, were portrayed as the "losers" in a "race" for the double helix, evidently won by Watson and Crick. As a result, both Franklin's work and her personality became the object of distortion.

Crick saw it differently: "After all, the structure was there waiting to be discovered—Watson and I did not invent it. It seems to me unlikely that either of us would have done it separately, but Rosalind Franklin was getting pretty close. She was in fact only two steps away. She needed to realize that the two chains were anti-parallel and to discover the base-pairing." Wilkins also acknowledged Franklin's contribution, posthumously, in his Nobel Lecture. Klug provided evidence, quoting Franklin's notebooks, that she was close to solving the DNA structure.

Her friend and biographer Anne Sayre suggested that Franklin might have been impeded in her progress on DNA by the problematic attitude towards women and minority researchers prevailing at King's College at that time. Although various authors lay emphasis on the clash of personalities at King's College, where Franklin was isolated, a key fact still remaining to be clarified concerns credit appropriation. Or, as F. R. Jevons put it: "Winner Takes All."

Franklin had too short a life to straighten the DNA record herself, having died of cancer on April 16, 1958, at the age of 37. How appropriate were J. D. Bernal's words: "Her early death is a great loss to science."

Further Reading

An assessment of Franklin's career was J. D. Bernal, "Dr. Rosalind E. Franklin" in Nature 182 (July 19, 1958). The three papers on DNA structure appeared in Nature 171 (April 25, 1953). On Franklin, see: Edward Garber, editor, Genetic Perspectives in Biology and Medicine (1985); John Gribbin, In Search of the Double Helix (1985); Frederick Raphael Jevons, Winner Takes All (1981); Horace Freeland Judson, The Eighth Day of Creation (1980); James D. Watson, The Double Helix. A Personal Account of the Discovery of the Structure of DNA, Gunther S. Stent, editor (1980; the original version, without reviews and comments, appeared in 1968); Pnina G. Abir-Am, "Review of A Century of DNA" in ISIS 69 (1978); Nicholas Wade, The Ultimate Experiment (1977); Maurice H. F. Wilkins, "The Molecular Configuration of Nucleic Acids," in Nobel Lectures in Molecular Biology 1933-1975 (1977); Anne Sayre, Rosalind Franklin and DNA (1975); A. Klug, "Rosalind Franklin and the Double Helix," (published together with eight other papers for the 21 years of the double helix) Nature 248 (April 26, 1974); and Robert Olby, The Path to the Double Helix (foreword by Francis Crick, 1974). □

Franklin, Rosalind Elsie

views updated May 29 2018

FRANKLIN, ROSALIND ELSIE

FRANKLIN, ROSALIND ELSIE (1920–1958), British biophysicist. Franklin was born in London, England, into an upper middle class Jewish family whose ancestors had come to England from Breslau in 1763. Her uncle, Sir Herbert *Samuel, was the first British High Commissioner to Palestine. In 1938 she was accepted to Newnham College Cambridge where she completed her studies in chemistry and physics and received her Ph.D. from Cambridge in the physical chemistry of carbon and graphite micro-structures (1945). During the war years she focused her research efforts on the analysis of high-strength carbon fibers, working at the British Coal Utilization Research Association (bcura), work that later found use in the construction of carbon rods in modern nuclear power plants. She moved to Paris and lived there from 1947 to 1951, joining the Central Government Laboratory for Chemistry. Working under Jacques Mering she became proficient in X-ray diffraction analysis of coal structure. During this time, in addition to her science she perfected her French and culinary arts, embraced French fashion, and generally enjoyed the freedom and respect as a scientist and colleague, devoid of the prejudice women had to endure in England. Nonetheless, as a foreigner in France, she understood that it would be hard for her to establish herself as an independent researcher and so she returned to England and joined Kings College in London under Sir John Randall. It was here that she produced the essential basic data that paved the way for James Watson and Francis Crick of Cambridge University to propose the double helix structure of dna, the molecule that genes are made of. At Kings College she and Maurice Wilkins independently studied dna structure. Franklin perfected the X-ray diffraction equipment and technology to produce highly focused X-ray beams to study the fine dna fibers she was able to extract. She soon discovered that dna could assume two forms, which she called a and b. Through painstaking work and extreme care and patience in sample preparation she produced photographs of both a and b forms that led her to conclude that dna was a double helical molecule in which the phosphate atoms must be on the outside of the structure and the nitrogen bases facing inside. These conclusions and Franklin's X-ray photographs enabled Watson and Crick to propose their double helix model of dna in which base pairing created the bonds necessary to hold the anti-parallel strands of dna together. In 1953, she moved to Birkbeck College to establish a new laboratory dedicated to the study of nucleic-acid protein complexes (when she left Kings College Sir Randall demanded that she stop working on dna!). Franklin turned to the study of Tobacco Mosaic Virus (tmv) and with a young investigator, Aaron *Klug, discovered that tmv was an extended tube in which its proteins were arranged in helical fashion with rna (ribonucleic acid) embedded amongst the protein molecules.

She made pivotal contributions in three areas of science; the analysis of the structure of carbon and coal, the elucidation of the structure of dna, and the new field of structural virology as a pioneer. In 1956 she was diagnosed with ovarian cancer. Despite three operations and experimental chemotherapy she courageously continued her work on tmv and polio virus until her dying day. Four years later, Francis Crick, James Watson, and Maurice Wilkins received the Nobel Prize in medicine and physiology for their discoveries concerning the structure of dna. In 1982 Sir Aaron Klug was awarded the Nobel Prize in chemistry for his structural elucidation of biologically important nucleic acid-protein complexes. It is not by chance that such profound science was so intimately associated with Rosalind Franklin. At the age of 37 she died of ovarian cancer, with little recognition of her monumental contributions to modern biophysics.

bibliography:

B. Maddox, Rosalind Franklin: The Dark Lady of dna (2002); A. Piper, "Light on a Dark Lady," in: Trends in Biochem. Sci. 23 (1998), 151–54; J.D. Watson, The Double Helix (1968).

[Jonathan Gershoni (2nd ed.)]

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