Glossary for "Defending Franklin's Legacy"
antiparallel: parallel but upside down with respect to each other
base-pairing: In a key insight on the road to discovering DNA's structure, Watson figured out that the four basic chemicals in DNA paired up as follows: adenine with thymine and guanine with cytosine.
John Desmond Bernal: An acclaimed crystallographer, Bernal was head of the physics department at Birkbeck College when Franklin joined the staff in March 1953. It was Bernal who wrote Franklin's obituaries.
Chargaff's ratios: Regarding DNA's base pairs, Erwin Chargaff discovered in 1952 that the total amount of adenine and guanine always equaled the total amount of thymine and cytosine.
coal researchers: Franklin worked on the molecular structure of coal early in her career.
Francis Crick: Co-discoverer, with James Watson, of the structure of DNA.
Jerry Donohue: Chemist sharing an office with Watson and Crick who suggested to Watson that he try modeling DNA with the enol rather than keto forms of the base pairs.
enol and keto forms: The four chemical bases come in two forms, enol and keto, each of which makes an oxygen atom available for bonding in a different position.
Franklin-Wilkins Building: Part of King's College London, where Franklin and Maurice Wilkins worked on the structure of DNA, this is the home of the college's Department of Pharmacy. Opened in 2000, it provides teaching and research facilities for 4,500 students.
Raymond Gosling: A doctoral candidate at King's College London, Gosling assisted Franklin in her X-ray diffraction work.
helical backbone: The basic structure, or scaffolding, of DNA is a double helix.
Dorothy Hodgkin: A crystallographer, Hodgkin won the Nobel Prize in chemistry in 1964.
hydrogen bonding: DNA's four chemical bases are bonded together by hydrogen atoms.
Aaron Klug: Chemist who collaborated with Franklin on her virus work in the mid-1950s. Klug received the Nobel Prize in chemistry in 1982.
March 17th draft: Written in March, 1953, by Franklin, this paper summarized Franklin's findings about the double-helix backbone in the B form of DNA. It was published alongside Watson and Crick's famous paper in the April 25th, 1953, issue of Nature.
MRC report: Franklin's portion of a 1952 Medical Research Council report inspired Watson and Crick to cease trying to put the bases on the outside of their burgeoning model of DNA.
Linus Pauling: The foremost chemist of his day, Pauling was trying to determine the structure of DNA at the same time as Watson and Crick. Pauling is the only person to ever win two Nobel Prizes—chemistry in 1954 and peace in 1962.
Anne and David Sayre: Anne Sayre published a biography of her good friend Franklin in 1975 (Rosalind Franklin and DNA, Norton). David Sayre, her husband, is a crystallographer.
sugar-phosphate groups: DNA's backbone is made up of sugar-phosphate groups to which the four bases adhere and point toward the helical axis.
34-angstrom measurements: Crystallographer William Astbury determined that DNA's base pairs lay flat, 3.4 angstroms apart, and that the distance between each turn of the helix is 34 angstroms.
two forms of DNA: Franklin discovered that DNA comes in two forms, which she labeled "A" and "B."
James Watson: Co-discoverer, with Francis Crick, of the structure of DNA.
Maurice Wilkins: A physicist at King's College London who was Franklin's immediate boss when she worked there. Wilkins shared the Nobel Prize in physiology or medicine with Watson and Crick in 1962.
X-ray work: Franklin used X-ray diffraction techniques to study the structure of DNA.