Cornforth, John Warcup (1917– )

Australian chemist. Using radioisotopes as markers, he found out how cholesterol is manufactured in the living cell and how enzymes synthesize chemicals that are mirror images of each other (optical isomers).

He shared the Nobel Prize for Chemistry in 1975 with Swiss chemist Vladimir Prelog for his work in the stereochemistry of enzyme-catalysed reactions. He was knighted in 1977.

Cornforth was born in Sydney and educated there and at Oxford University. He settled in the UK in 1941, and worked for the British Medical Research Council 1946–62, when he became director of the Milstead Laboratory of Chemical Enzymology, Shell Research Ltd. He remained there until 1975, when he accepted a professorship at the University of Sussex.

In his researches, Cornforth studied enzymes, trying to determine specifically which group of hydrogen atoms in a biologically active compound is replaced by an enzyme to bring about a given effect. By using the element's three isotopes, he was able to identify precisely which hydrogen atom was affected by enzyme action. He was able, for example, to establish the orientation of all the hydrogen atoms in the cholesterol molecule.