Alexander Fleming

Scottish biologist, pharmacologist and botanist whose best-known discoveries are the enzyme lysozyme in 1923 and the world's first antibiotic substance benzylpenicillin (Penicillin G) from the mould Penicillium notatum in 1928, for which he shared the Nobel Prize in Physiology or Medicine in 1945 with Howard Florey and Ernst Boris Chain. He was elected to the Royal Society in 1943, and knighted by King George VI in 1944.

After a two week holiday, in September 1928 he returned to his laboratory to find a strange mould growing on a specimen. He deduced the mould had antibacterial properties and identified Penicillium notatum calling it penicillin. Penicillin had been seen before, but Fleming's cognitive abilities allowed him to recognize what it could do. He published his findings in 1929 but abandoned the work in 1932 due to lack of expertise to purify the substance and he did not hold the conviction that drugs could cure a serious infection as the body's immune system should. In 1939 he provided some penicillin to Sir Howard Florey and Ernst Chain. They did the chemical work and in 1945 they all shared the Nobel prize in Medicine. As Fleming seemed to revel in publicity, he became the spokesman for the other scientists.

Born seventh of eight siblings and half-siblings to a sheep farming family, Alexander excelled in school. After his father's death he moved to London at about 14. As an adult he was short in stature, usually wore a bow tie and never mastered the conventions of polite society.

In 1900 he and two brothers joined a Scottish regiment to fight in the Boer War. In 1901 he entered medical school at Saint Mary's Hospital, London. He became a fellow of the Royal College of Surgeons in 1909. After serving as a captain in the Army Medical Corps in World War I, Fleming became a professor in 1919 and a research scientist with a profitable side practice of treating syphilis infections of prominent London artists.