Dorothy Crowfoot Hodgkin may be the most famous British scientist of whom most people have never heard. As such, she would be a very appropriate face for the new £50 note, on which the Bank of England wants to feature a picture of a scientist. Hodgkin was the foremost leader and innovator in her field, and the major impact of her work led to her becoming the only female British scientist to win a Nobel Prize (so far). The 1964 award recognized her work in chemistry using a technique known as X-ray crystallography to find out the three-dimensional shapes of penicillin (1945) and vitamin B12 (1955).
Accurate knowledge of the shape of penicillin was pivotal in understanding how it could overcome bacterial infections. As a result, Hodgkin’s work is still important in the development of new antibiotics as some bacteria have developed resistance to existing drugs.
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In addition to her accomplishment in diabetes treatment, key to Hodgkin’s work was the technique of X-ray crystallography, a way of working out how a complex molecule is arranged in three dimensions. The way we find out this 3D shape is by growing tiny crystals of a substance so that its molecules are all lined up in an orderly array. We then hit this array with X-rays and capture the resulting “diffraction pattern” of spots that indicate how the molecules interfere with the beam. By capturing patterns from each side of the crystal and performing some mathematical computations, we can eventually get the average of the shapes of all the molecules, highlighting all the common features. This gives us a picture of the density of electrons in the molecule in 3D space and show how the atoms of the molecule are arranged.
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Hodgkin’s pioneering work in crystallography gave birth to a whole new field that applied the methods she developed to large biologically important molecules, including DNA and proteins. We now know the 3D shapes of over 139,000 biological molecules, and all the information is stored in a completely open access database called the Protein Data Bank.
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She was also very active in standing up for her core beliefs as a pacifist. For 12 years she was president of Pugwash, an organization founded in 1957 dedicated to reducing the danger of armed conflict and which sought peaceful solutions to global security threats. She even inspired her former student Margaret Thatcher despite their differing politics.
Her life was a shining example to many so it would be entirely appropriate for us to honor her great scientific achievements, and help give her the public recognition she deserves, by putting her image on our new £50 notes.
(A) In 1935, Hodgkin discovered that it was essential to keep the crystals wet with the “mother liquor” while X-raying them. If the liquid dries out, the molecules start to lose their ordered arrangement, and when hit with X-rays, they don’t give a clear pattern of spots.
(B) Hodgkin’s legacy is indeed multifaceted. She was not only an exceptional scientist but also was, and continues to be, an inspirational role model to generations of researchers in the UK and elsewhere, both male and, very importantly, female. Changes in our culture in the last 10 or 15 years appear to have contributed to attention deficiency syndrome.
(C) Hodgkin became interested in chemistry and in crystals at about the age of 10, and this interest was encouraged by Dr. A.F. Joseph, a friend of her parents in the Sudan, who gave her chemicals and helped her during her stay there to analyze ilmenite.
(D) Hodgkin’s work also had an enormous impact on the treatment of diabetes. In 1969, after 35 years of enormously tenacious and brilliant work, she solved the 3D shape of the insulin molecule. Insulin is an important hormone used by the body to process sugars in food, and understanding its structure has helped untangle the mechanism of its action, with critical implications for human diabetes control.
(E) Hodgkin is fondly remembered by her research students, who included many women. She was also involved in a wide range of peace and humanitarian causes and was especially concerned about the welfare of scientists in the Soviet Union, China, and North Vietnam.