Frederick Sanger

Frederick Sanger was born on 13 August 1918 in Rendcomb, Gloucestershire, England, and died on 19 November 2013 in Cambridge. He earned his PhD at St John's College, Cambridge in 1943, joined Charles Chibnall's protein chemistry group there, and later became head of the Protein Chemistry division of the Medical Research Council's Laboratory of Molecular Biology in 1962. Between 1945 and 1955 he determined the complete amino acid sequence of bovine insulin, both its A and B chains and the three disulfide bonds linking them, using his own reagent, 1-fluoro-2,4-dinitrobenzene, now called Sanger's reagent, to label and trace each chain's terminal amino acid. The work proved for the first time that a protein has one exact, fixed sequence of amino acids rather than a loose or variable composition, and won him the Nobel Prize in Chemistry in 1958. In 1980 he shared a second Nobel Prize in Chemistry, with Walter Gilbert and Paul Berg, for the dideoxy chain-termination method of DNA sequencing that bears his name and that later made the Human Genome Project possible; he remains the only person to have won the Nobel Prize in Chemistry twice.