Maurice Wilkins

Maurice Wilkins

Maurice Wilkins
Born 15 December 1916(1916-12-15)
Pongaroa, Wairarapa,
New Zealand
Died 5 October 2004(2004-10-05) (aged 87)
Blackheath, London,
United Kingdom
Fields molecular biologist,
Known for X-ray diffraction, DNA
Notable awards Nobel Prize in Physiology or Medicine (1962)

Maurice Hugh Frederick Wilkins CBE FRS (15 December 1916 – 5 October 2004) was a New Zealand-born British molecular biologist, and Nobel Laureate who contributed research in the fields of phosphorescence, radar, isotope separation, and X-ray diffraction. He was most widely known for his work at King's College London on the structure of DNA. In recognition of this work, he, Francis Crick and James Watson were awarded the 1962 Nobel Prize for Physiology or Medicine, "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material."[1]

Contents

Birth and education

Monument to Maurice Wilkins, Main Street, Pongaroa, New Zealand

Wilkins was born in Pongaroa, north Wairarapa, New Zealand where his father, Edgar Henry Wilkins was a medical doctor. His family moved to Birmingham, England when he was 6, where he subsequently attended Wylde Green College and then King Edward's School at the age of 12. He later studied physics at St John's College, Cambridge, then in 1940 he received his Ph.D. in physics at the University of Birmingham with a dissertation on phosphors. During World War II he developed improved radar screens at Birmingham, then worked on isotope separation at the Manhattan Project at the University of California, Berkeley for two years before returning to King's College London. Formerly classified UK security service papers reveal that, while working on the project, Wilkins came under suspicion of leaking atomic secrets. The files, released in August 2010, indicate surveillance of Wilkins ended by 1953.[2] "After the war I wondered what I would do, as I was very disgusted with the dropping of two bombs on civilian centres in Japan," he told Britain's Encounter radio programme in 1999.[3]

Academic career

In 1946 the physicist John Randall was placed in charge of a new biophysics laboratory at King's College. The plan was to hire physicists such as Wilkins to work on problems in biology. When Francis Crick first met Wilkins he was not convinced that the King's College laboratory had anything like a clear plan of attack. There seemed to be a vague hope that by applying techniques like Ultraviolet light microscopy (Wilkins) and electron microscopy (Randall), new insights could be gained into cell structure and function. By 1950, Randall was gearing up the laboratory for work on proteins. His original plan for Rosalind Franklin was that she do X-ray diffraction studies on proteins. Wilkins' work on DNA changed that. By 1951, Randall had established a major effort to solve the structure of collagen and Wilkins and Franklin represented a parallel effort to determine the structure of DNA. In the meantime, Maurice Wilkins' friend Francis Crick had joined forces with James Watson under the supervision of Max Perutz at the Cavendish Laboratory, Cambridge and under the overall direction of Lawrence Bragg.

DNA

At King's College Wilkins pursued, among other things x-ray diffraction work on DNA that had been obtained from calf thymus by the Swiss scientist Rudolf Signer. The DNA from Signer's lab was much more intact than the DNA which had previously been isolated. Wilkins discovered that it was possible to produce thin threads from this concentrated DNA solution that contained highly ordered arrays of DNA suitable for the production of x-ray diffraction patterns.[4] Using a carefully bundled group of these DNA threads and keeping them hydrated, Wilkins and a graduate student Raymond Gosling obtained x-ray photographs of DNA that showed that the long, thin DNA molecule in the sample from Signer had a regular, crystal-like structure in these threads. This initial x-ray diffraction work at Kings College was done in May or June 1950. It was one of the x-ray diffraction photographs taken in 1950, shown at a meeting in Naples a year later, that sparked James Watson’s interest in DNA.

At that time Wilkins also introduced Francis Crick to the importance of DNA. Wilkins knew that proper experiments on the threads of purified DNA would require better x-ray equipment. Wilkins ordered a new x-ray tube and a new microcamera. Before the DNA sample from Signer was available, Gosling had been trying to make x-ray diffraction images of sperm. However, Franklin did not start using the new equipment until September 1951. By the summer of 1950 Randall had arranged for a three year research fellowship that would fund Rosalind Franklin in his laboratory. Franklin was delayed in finishing her work in Paris. Late in 1950, Randall wrote to Franklin to inform her that rather than work on protein, she should take advantage of Wilkins's preliminary work and that she should do x-ray studies of DNA fibers made from Signer's samples of DNA. Early in 1951 Franklin finally arrived. Wilkins was away on holiday and missed an initial meeting at which Raymond Gosling stood in for him along with Alex Stokes, who, like Crick, would solve the basic mathematics that make possible a general theory of how helical structures diffract x-rays. No work had been done on DNA in the laboratory for several months; the new x-ray tube sat unused, waiting for Franklin. Franklin ended up with the DNA from Signer, Gosling became her PhD student, and she had the expectation that DNA x-ray diffraction work was her project. Wilkins returned to the laboratory expecting that Franklin would be his collaborator and that they would work together on the DNA project that he had started. Franklin felt that DNA was now her project and would not collaborate with Wilkins, who then pursued parallel studies.

By November 1951 Wilkins had evidence that DNA in cells as well as purified DNA had a helical structure.[5] Alex Stokes had solved the basic mathematics of helical diffraction theory and thought that Wilkins's x-ray diffraction data indicated a helical structure in DNA. Wilkins met with Watson and Crick and told them about his results. This information from Wilkins, along with additional information gained by Watson when he heard Franklin talk about her research during a King's College research meeting, stimulated Watson and Crick to create their first molecular model of DNA, a model with the phosphate backbones at the center. Upon viewing the model of the proposed structure, Franklin told Watson and Crick that it was wrong. Franklin knew from basic chemical principles the hydrophilic backbones should go on the outside of the molecule where they could interact with water. Crick tried to get Wilkins to continue with additional molecular modeling efforts, but Wilkins did not take this approach. During 1952, Franklin also refused to participate in molecular modeling efforts and continued to work on step-by-step detailed analysis of her x-ray diffraction data (Patterson synthesis). By the spring of 1952, Franklin had received permission from Randall to ask to transfer her fellowship so that she could leave King's College and work in John Bernal's laboratory at Birkbeck College, also in London. However, Franklin remained at King's College for another year.

By early 1953, it was clear that Franklin would simply drop her DNA work at the end of her fellowship that summer, or even sooner due to illness. Linus Pauling had published a proposed but incorrect structure of DNA, making the same basic error that Watson and Crick had made a year earlier. Some of those working on DNA in the United Kingdom feared that Pauling would quickly solve the DNA structure once he recognized his error and put the backbones of the nucleotide chains on the outside of a model of DNA. After March 1952 Franklin concentrated on the x-ray data for the A-form of less hydrated DNA while Wilkins tried to work on the hydrated B-form. Wilkins was handicapped because Franklin had all of the good DNA. Wilkins got new DNA samples, but it was not as good as the original sample he had used in 1950 and which Franklin continued to use. Most of his new results were for biological samples like sperm cells, which seemed to also suggest a helical structure for DNA. In the middle of 1952 Wilkins had for a time abandoned further DNA work when Franklin reported to him that her results made her doubt the helical nature of the A-form. Wilkins feared that the data suggesting a helical structure might just be an artifact.

In early 1953 Watson visited King's College and Wilkins showed him a high quality image of the B-form x-ray diffraction pattern, now nicknamed photo 51, that Franklin had produced in March 1952. With the knowledge that Pauling was working on DNA and had submitted a model of DNA for publication, Watson and Crick mounted one more concentrated effort to deduce the structure of DNA. Through Max Perutz, his thesis supervisor, Crick gained access to a progress report from King's College that included useful information from Franklin about the features of DNA she had deduced from her x-ray diffraction data. Watson and Crick published their proposed DNA double helical structure in a paper in the journal Nature in April 1953. In this paper Watson and Crick acknowledged that they had been "stimulated by.... the unpublished results and ideas" of Wilkins and Franklin.

The discovery itself was made on 28 February 1953 by Watson and Crick; the first Watson-Crick paper appeared in Nature on 25 April 1953. Sir Lawrence Bragg, the director of the Cavendish Laboratory, where Watson and Crick worked, gave a talk at Guys Hospital Medical School in London on Thursday 14 May 1953 which resulted in an article by Ritchie Calder in the News Chronicle of London, on Friday 15 May 1953, entitled "Why You Are You. Nearer Secret of Life." The news reached readers of The New York Times the next day; Victor K. McElheny, in researching his biography of Watson, Watson and DNA: Making a Scientific Revolution, found a clipping of a six-paragraph New York Times article written from London and dated 16 May 1953 with the headline "Form of 'Life Unit' in Cell Is Scanned." The article ran in an early edition and was then pulled to make space for news deemed more important. (The New York Times subsequently ran a longer article on 12 June 1953). The Cambridge University undergraduate newspaper Varsity also ran its own short article on the discovery on Saturday 30 May 1953. Bragg's original announcement at a Solvay conference on proteins in Belgium on 8 April 1953 went unreported by the press.

In recognition of the contribution from King's College, Watson and Crick agreed that Wilkins, Stokes, and Wilson[6] and Franklin and Gosling should each publish their x-ray diffraction work, which supported the proposed Crick-Watson model, in separate articles in the same issue of Nature.

Wilkins and others went on to repeat and extend much of Franklin's work, and produced abundant evidence to support the helical model produced by Crick and Watson.

Personal life

Wilkins married his second wife Patricia Ann Chidgey in 1959. They had four children, Sarah, George, Emily and William; he had a son by his previous marriage, to an art student called Ruth in California.

He published his autobiography, The Third Man of the Double Helix, in 2003, but does not specifically credit Stokes and Wilson as co-authors of their paper in Nature. Whether this was deliberate on his part or just the result of poor sub-editing by the publisher is not known.

Recognition

A plaque commemorating Maurice Wilkins and his discovery, beneath the monument, Pongaroa, New Zealand

In 1960 he was presented with the American Public Health Association's Albert Lasker Award, and in 1962 he was made a Commander of the British Empire. Also in 1962 he shared the Nobel Prize in Physiology or Medicine with Watson and Crick for the discovery of the structure of DNA.

On Saturday 20 October 1962 the award of Nobel prizes to John Kendrew and Max Perutz, and to Crick, Watson, and Wilkins was satirised in a short sketch in the BBC TV programme That Was The Week That Was with the Nobel Prizes being referred to as 'The Alfred Nobel Peace Pools.'

In 2000, King's College London opened the Franklin-Wilkins Building in honour of Dr. Franklin's and Professor Wilkins' work at the college.[7]

The wording on the new DNA sculpture (which was donated by James Watson) outside Clare College's Thirkill Court, Cambridge, England is

a) on the base:

i) "These strands unravel during cell reproduction. Genes are encoded in the sequence of bases."
ii) "The double helix model was supported by the work of Rosalind Franklin and Maurice Wilkins."

b) on the helices:

i) "The structure of DNA was discovered in 1953 by Francis Crick and James Watson while Watson lived here at Clare."
ii) "The molecule of DNA has two helical strands that are linked by base pairs Adenine - Thymine or Guanine - Cytosine."

References

  1. ↑ The Nobel Prize in Physiology or Medicine 1962. Nobel Prize Site for Nobel Prize in Physiology or Medicine 1962.
  2. ↑ Alan Travis "Nobel-winning British scientist accused of spying by MI5, papers reveal", The Guardian, 26 August 2010
  3. ↑ "A Bunch of Genes". Radio National. 4 July 1999. http://www.abc.net.au/rn/relig/enc/stories/s39549.htm. Retrieved 2009-02-20. 
  4. ↑ See Figure 1 of the Nobel lecture by Wilkins. See other examples at the King's College website for DNA structure.
  5. ↑ See Chapter 2 of The Eighth Day of Creation: Makers of the Revolution in Biology by Horace Freeland Judson published by Cold Spring Harbor Laboratory Press (1996) ISBN 0-87969-478-5.
  6. ↑ "Molecular Structure of Deoxypentose Nucleic Acids" by M. H. F. Wilkins, A.R. Stokes A.R. and H. R. Wilson in Nature (1953) volume 171, p. 738-740. Download the full text in PDF format.
  7. ↑ Maddox, p. 323
  1. Watson, James D. "The Double Helix: A Personal Account of the Discovery of the Structure of DNA"; The Norton Critical Edition, which was published in 1980, edited by Gunther S. Stent.

Books featuring Maurice Wilkins

External links

DNA structure research at King's College London 1947-1959
Rosalind Franklin · Raymond Gosling · John Randall · Alexander Stokes · Maurice Wilkins · Herbert Wilson
 DNA-fragment-3D-vdW.png
Nobel Laureates in Physiology or Medicine

Max Theiler (1951) · Selman Waksman (1952) · Hans Krebs / Fritz Lipmann (1953) · John Enders / Thomas Weller / Frederick Robbins (1954) · Hugo Theorell (1955) · André Cournand / Werner Forssmann / Dickinson W. Richards (1956) · Daniel Bovet (1957) · George Beadle / Edward Tatum / Joshua Lederberg (1958) · Severo Ochoa / Arthur Kornberg (1959) · Frank Burnet / Peter Medawar (1960) · Georg von Békésy (1961) · Francis Crick / James D. Watson / Maurice Wilkins (1962) · John Eccles / Alan Hodgkin / Andrew Huxley (1963) · Konrad Bloch / Feodor Lynen (1964) · François Jacob / André Lwoff / Jacques Monod (1965) · Francis Rous / Charles B. Huggins (1966) · Ragnar Granit / Haldan Hartline / George Wald (1967) · Robert W. Holley / Har Khorana / Marshall Nirenberg (1968) · Max Delbrück / Alfred Hershey / Salvador Luria (1969) · Bernard Katz / Ulf von Euler / Julius Axelrod (1970) · Earl Sutherland, Jr. (1971) · Gerald Edelman / Rodney Porter (1972) · Karl von Frisch / Konrad Lorenz / Nikolaas Tinbergen (1973) · Albert Claude / Christian de Duve / George Palade (1974) · David Baltimore / Renato Dulbecco / Howard Temin (1975)
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