'Alexander Fleming Prix Nobel 1945'.
© Science Museum / Science & Society Picture Library
Nobel prize medal awarded to Alexander Fleming (1881-1955). In 1928 Alexander Fleming (1881-1955) had discovered that a strain of penicillium mould exuded a substance which killed certain bacteria. Following the German firm IG Farben's announcement of the first general purpose bacteria-killing drug Prontosil, Fleming now saw it as a posible medicine and gave this sample to a colleague at St Mary's Hospital, London. Penicillin was eventually isolated in 1939, and from 1942 became an important drug. Although the work leading to this was largely carried out by Howard Florey and Ernst Chain, Fleming shared the Nobel Prize for Medicine with them in 1945.