Photo credit: Frederick Sanger — File:Frederick Sanger2.jpg (Wikimedia Commons) · Public domain
Frederick Sanger
1918–2013 · United Kingdom · 20th century
Nobel Chemistry 1958Nobel Chemistry 1980
Determined the amino-acid sequence of insulin and developed DNA sequencing; one of only two people to win the chemistry prize twice.
Nobel Prize work
The 1958 Nobel Prize in Chemistry honored his determination of the structure of proteins, above all insulin: tagging free amino groups with fluorodinitrobenzene and fragmenting the chains, he sequenced insulin's 51 amino-acid residues — the first protein sequence ever obtained, proving proteins have a defined covalent structure. The 1980 prize (shared) recognized his methods for sequencing nucleic acids, above all the dideoxy chain-termination method published in 1977 that became the standard way to read DNA.