Penicillin discovered by Alexander Fleming in 1928

Sir Alexander Fleming (6 August 1881 – 11 March 1955) was a Scottish physician and microbiologist. He shared the 1945 Nobel Prize in Physiology or Medicine with Howard Florey and Ernst Chain 'for the discovery of penicillin and its curative effect in various infectious diseases'. This recognition marked the first antibiotic substance to be discovered.

In 1928 he identified benzylpenicillin (also known as penicillin G) from the mould Penicillium rubens, a discovery that has been described as the 'single greatest victory ever achieved over disease'.

He also discovered the enzyme lysozyme in his nasal discharge in 1922, and he named a bacterium Micrococcus lysodeiktikus, later Micrococcus luteus.

Fleming was knighted for his scientific achievements in 1944.

In 1999 Time magazine named him in its list of the 100 Most Important People of the 20th century. In 2002, he was included in the BBC's television poll of the 100 Greatest Britons, and in 2009, he was voted third 'greatest Scot' in an STV opinion poll, behind only Robert Burns and William Wallace.