Alexander Fleming
Scottish physician and microbiologist who discovered the first antibiotic, penicillin, in 1928.
Alexander Fleming, a Scottish physician and microbiologist, was born on 6 August 1881 and died on 11 March 1955. He is best known for discovering the first antibiotic substance, penicillin. In 1945, he shared the Nobel Prize in Physiology or Medicine with Howard Florey and Ernst Chain for identifying penicillin and its ability to cure various infectious diseases. His 1928 discovery of what became known as benzylpenicillin (or penicillin G) from the mould *Penicillium rubens* has been called the single greatest victory ever achieved over disease.
Earlier, in 1922, Fleming discovered the enzyme lysozyme from his own nasal mucus. Alongside this, he identified a bacterium he named *Micrococcus lysodeikticus*, later reclassified as *Micrococcus luteus*. For his scientific work, he was knighted in 1944.
Fleming grew up on a farm near Darvel in Ayrshire, Scotland, the third of four children born to farmer Hugh Fleming and Grace Stirling Morton. His father, who had four surviving children from a previous marriage, was 59 when he married Grace and died when Alexander was seven. After attending local schools and earning a scholarship to Kilmarnock Academy, Fleming moved to London for the Royal Polytechnic Institution. He worked in a shipping office for four years, then inherited money from an uncle. Following his older brother Tom, a physician, Fleming enrolled at St Mary's Hospital Medical School in 1901, earning his MBBS with distinction in 1906.
From 1900 to 1914, Fleming served as a private in the London Scottish Regiment of the Volunteer Force and was a member of his medical school’s rifle club. The club captain, wanting to keep him on the team, suggested he join St Mary’s research department. There, he became assistant bacteriologist to Sir Almroth Wright, a pioneer in vaccine therapy and immunology. In 1908, he earned a BSc with a gold medal in bacteriology and lectured at St Mary’s until 1914.
Commissioned as a lieutenant in 1914 and promoted to captain in 1917, Fleming served throughout World War I with the Royal Army Medical Corps and was Mentioned in Dispatches. He and colleagues worked in battlefield hospitals on the Western Front in France. In 1918, he returned to St Mary’s, becoming Professor of Bacteriology at the University of London in 1928.
During the war, Fleming, along with Leonard Colebrook and Almroth Wright, moved St Mary’s Inoculation Department to a British military hospital in Boulogne-sur-Mer. As a temporary lieutenant, he saw many soldiers die from sepsis from infected wounds. He observed that antiseptics often made injuries worse. In a 1917 *Lancet* article, he described an experiment—made possible by his own glassblowing skills—showing that antiseptics worked on surfaces but not in deep wounds, where they sheltered anaerobic bacteria and removed helpful protective agents. Despite Wright’s support, most army physicians kept using antiseptics even when they worsened patients’ conditions.
Back at St Mary’s, Fleming continued studying bacteria and antibacterial substances. His research scholar V. D. Allison recalled that Fleming was not a tidy researcher and often expected unusual bacterial growths on his culture plates. Fleming teased Allison for being too tidy, and Allison later said that if Fleming had been as tidy as he thought Allison was, he would not have made his two great discoveries.
In late 1921, while maintaining agar plates, Fleming found one contaminated with airborne bacteria. When he added nasal mucus, the mucus inhibited bacterial growth, creating a clear killing zone around it. In a further test, fresh mucus turned a yellow bacterial suspension completely clear within two minutes. He then tested tears, supplied by co-workers. Allison remembered that for five or six weeks, their tears were the source for this phenomenon. They used lemons (after onions failed) to produce tears, and laboratory attendants were paid threepence for each contribution.
- born
- 6 August 1881
- died
- 11 March 1955
- field
- Physician and microbiologist
- nationality
- Scottish
- known_for
- Discovery of penicillin and lysozyme
Lore & Background
Born on 6 August 1881 at Lochfield farm near Darvel, in Ayrshire, Scotland, Alexander Fleming was the third of four children of farmer Hugh Fleming and Grace Stirling Morton. Hugh Fleming had four surviving children from his first marriage. He was 59 at the time of his second marriage to Grace, and died when Alexander was seven. Fleming went to Loudoun Moor School and Darvel School, and earned a two-year scholarship to Kilmarnock Academy before moving to London, where he attended the Royal Polytechnic Institution. After working in a shipping office for four years, the twenty-year-old Alexander Fleming inherited some money from an uncle, John Fleming. His elder brother, Tom, was already a physician and suggested that he should follow the same career. In 1901, the younger Alexander enrolled at St Mary's Hospital Medical School in Paddington, now part of Imperial College London. In 1906, he qualified with an MBBS degree from the school with distinction. Fleming, who was a private in the London Scottish Regiment of the Volunteer Force from 1900 to 1914, had been a member of the rifle club at the medical school. The captain of the club suggested that he join the research department at St Mary's, where he became assistant bacteriologist to Sir Almroth Wright. In 1908, he gained a BSc degree with gold medal in bacteriology, and became a lecturer at St Mary's until 1914. Commissioned lieutenant in 1914 and promoted captain in 1917, Fleming served throughout World War I in the Royal Army Medical Corps, and was Mentioned in Dispatches. In 1918 he returned to St Mary's Hospital, where he was elected Professor of Bacteriology of the University of London in 1928.
Reader's Guide
During World War I, Fleming with Leonard Colebrook and Sir Almroth Wright joined the war efforts and practically moved the entire Inoculation Department of St Mary's to the British military hospital at Boulogne-sur-Mer. Serving as a temporary lieutenant of the Royal Army Medical Corps, he witnessed the death of many soldiers from sepsis resulting from infected wounds. Antiseptics, which were used at the time to treat infected wounds, he observed, often worsened the injuries. In a 1917 article published in The Lancet, he described an experiment explaining why antiseptics were killing more soldiers than infection itself during the war. Antiseptics worked well on the surface, but deep wounds tended to shelter anaerobic bacteria from the antiseptic agent, and antiseptics seemed to remove beneficial agents produced that protected the patients. Wright strongly supported Fleming's findings, but most army physicians continued to use antiseptics even in cases where this worsened the condition of the patients. At St Mary's Hospital, Fleming continued his investigations into bacteria culture and antibacterial substances. In late 1921, while maintaining agar plates for bacteria, he found that one of the plates was contaminated with bacteria from the air. When he added nasal mucus, he found that the mucus inhibited the bacterial growth. He extended his tests using tears, sputum, cartilage, blood, semen, ovarian cyst fluid, pus, and egg white, showing that the bactericidal agent was present in all of these. He reported his discovery before the Medical Research Club in December 1921 and before the Royal Society the next year but failed to stir any interest. Reporting in the 1 May 1922 issue of the Proceedings of the Royal Society B: Biological Sciences under the title 'On a remarkable bacteriolytic element found in tissues and secretions', Fleming wrote about a substance he called 'Lysozyme'. This was the first recorded discovery of lysozyme. With Allison, he published further studies on lysozyme in October issue of the British Journal of Experimental Pathology the same year. The enzyme was only effective against small counts of harmless bacteria, and therefore had little therapeutic potential. He also identified the bacterium present in the nasal mucus as Micrococcus lysodeikticus, later renamed Micrococcus luteus.
Did You Know?
- Fleming discovered lysozyme from his own nasal discharge in 1921, and the bacterium he isolated from it was later renamed Micrococcus luteus.
- Fleming's 1917 Lancet article argued that antiseptics were killing more soldiers than infection itself during World War I.
- Fleming was a private in the London Scottish Regiment of the Volunteer Force from 1900 to 1914.
- In 1999, Fleming was named in Time magazine's list of the 100 Most Important People of the 20th century.
Notable Quotes (Wikiquote)
"How fortunate we didn't have these animal tests in the 1940s, for penicillin would probably not have been granted a licence, and possibly the whole field of antibiotics might never have been realised." — Alexander Fleming "Reported in Dennis V. Parke, "Clinical Pharmacokinetics in Drug Safety Evaluation," in ATLA: Alternatives To Laboratory Animals, vol. 22, no. 3, May/June 1994, p. 208." — Alexander Fleming "When I woke up just after dawn on September 28, 1928, I certainly didn’t plan to revolutionize all medicine by discovering the world’s first antibiotic, or bacteria killer, ... But I guess that was exactly what I did." — Alexander Fleming "Lecture at Harvard University. Quoted in Joseph Sambrook, David W. Russell, Molecular Cloning (2001), Vol. 1, 153." — Alexander Fleming
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