Sir Alexander Fleming


Sir Alexander Fleming

Photo from the Nobel Foundation archive.

Sir Alexander Fleming
The Nobel Prize in Physiology or Medicine 1945

Born: 6 August 1881, Lochfield, Scotland

Died: 11 March 1955, London, United Kingdom

Affiliation at the time of the award: London University, London, United Kingdom

Prize motivation: “for the discovery of penicillin and its curative effect in various infectious diseases”

Prize share: 1/3


Among microorganisms, life is a constant battle for survival. Alexander Fleming became interested in this. He used to leave bowls with bacteria cultures standing by his worktable. In 1928 he saw that in addition to bacteria, a mold fungus had begun to grow in a bowl and that the bacteria's growth had been impeded in the vicinity of the mold. He concluded that the mold contained a substance that was effective against bacteria. The substance was given the name penicillin and became the basis for medication to treat bacterial infections.

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