Sir Alexander Fleming lived from 6 August 1881 to 11 March 1955. An eminent biologist, he is primarily remembered for his discovery in 1928 of the antibiotic penicillin. The wider picture in Scotland at the time is set out in our Historical Timeline.
Alexander Fleming was born at Lochfield Farm, a little north of Darvel in East Ayrshire. He was educated at Loudoun Moor School, Darvel School, and then Kilmarnock Academy before leaving at the age of 16 to work in a shipping office. At the age of 20 he inherited money from an uncle and in 1901 he enrolled as a medical student at St Mary's Hospital, Paddington, in London. He graduated in 1906 and was planning to follow a career as a surgeon when, by chance, he instead became an assistant bacteriologist to Sir Almroth Wright, a pioneer in vaccine therapy and immunology at St Mary's. From 1908 he lectured at St Mary's.
During the First World War, Fleming served as as a captain in the Army Medical Corps, spending much of the war in army hospitals in France. Here he continued his work on the limited effectiveness of the antiseptic agents then available and ways of improving them in the testing conditions of the western front. On 23 December 1915, he married a nurse, Sarah McElroy. After the war, Alexander Fleming returned to St Mary's, where he became Professor of Bacteriology in 1928.
In 1922 Fleming made his first major discovery when he isolated the enzyme lysozyme, one of a family of enzymes that can damage bacterial cell walls. But this was eclipsed by his discovery of penicillin in 1928. On 28 September 1928, after returning from a holiday, he discovered that some discarded petri-dishes had become contaminated by a fungus. The fungus seemed to be preventing the growth of nearby bacteria. Fleming subsequently named an extract from the mould penicillin. He published his findings in 1929, and continued low level research through the 1930s. From late 1941 Fleming's work was carried forward by Howard Florey and Ernst Boris Chain, and with government funding they were eventually able to produce penicillin in sufficient quantity for it to become widely available in the latter part of the Second World War. Such was its impact that Fleming, Florey and Chain shared the Nobel Prize in Physiology or Medicine in 1945 for their work on penicillin. Fleming was also knighted for his discovery of penicillin in 1944.
Sir Alexander Fleming died of a heart attack in 1955. His ashes were interred in St Paul's Cathedral. He is widely remembered for his discovery of penicillin and the laboratory at St Mary's Hospital is now home to the Fleming Museum. His name also lives on in the Alexander Fleming Middle School near Los Angeles in California.