Scottish bacteriologist who in 1928 noticed a mould (Penicillium notatum) had contaminated a petri dish and killed surrounding Staphylococcus bacteria. He named the active substance penicillin and published his findings, but could not isolate a stable form. It was Howard Florey and Ernst Chain at Oxford who purified penicillin in 1940 and proved its clinical value. Fleming, Florey, and Chain shared the 1945 Nobel Prize in Physiology or Medicine. Penicillin revolutionised the treatment of bacterial infection and saved hundreds of millions of lives.
- Nationality: scottish
- Roles: bacteriologist, physician
