Alexander Fleming
Born 1881 · Age 144
Scottish physician and microbiologist; discovered lysozyme (1921) and penicillin (1928); shared 1945 Nobel Prize in Physiology or Medicine with Howard Florey and Ernst Chain.
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Life & Career Timeline
Born at Lochfield Farm, Darvel, Ayrshire, Scotland
Alexander Fleming born to Hugh Fleming and Grace Stirling Morton at Lochfield Farm near Darvel.
Moved to London to live with elder brother and continue education
At about age 13 Fleming moved to London to increase educational opportunities and lived with his elder brother Thomas.
Enrolled at Regent Street Polytechnic
Attended Regent Street Polytechnic for approximately three years to complete basic education in London.
Worked as a shipping clerk in London
After leaving Polytechnic economic necessity forced Fleming to take a job as a clerk for a shipping company (period lasted ~4 years).
Joined London Scottish Regiment (Territorial Army)
Served as a private in the London Scottish Regiment from 1900 to 1914 (Territorial/Volunteer service).
Entered St. Mary's Hospital Medical School
Used scholarship and legacy from an uncle to enroll at St. Mary's Hospital Medical School, University of London.
Qualified MBBS with distinction (University of London)
Completed medical studies at St. Mary's and qualified with distinction in 1906.
Joined Inoculation Department under Sir Almroth Wright
Became assistant bacteriologist/research assistant in the Inoculation Department at St. Mary's under Almroth Wright.
Awarded BSc with gold medal in bacteriology
Gained a BSc degree with a gold medal in bacteriology (University of London), strengthening research credentials.
Elected Fellow of the Royal College of Surgeons (FRCS)
Passed Fellowship exams and accepted as a Fellow of the Royal College of Surgeons but chose research over surgical practice.
Established private venereology practice
Between 1909 and 1914 Fleming ran a successful private practice as a venereologist, administering treatments such as Salvarsan.
Commissioned in Royal Army Medical Corps (WWI)
Commissioned as lieutenant in RAMC at the outbreak of World War I and posted to field/laboratory work (Boulogne).
Married Sarah Marion McElroy
Married Sarah Marion McElroy, an Irish-trained nurse, on Christmas Eve 1915.
Published Lancet paper on antiseptics and leukocytes
Published experiments (1917) demonstrating antiseptics could damage leukocytes and worsen wound outcomes in field conditions.
Promoted to Captain in RAMC
Promoted to captain during World War I while serving in the Army Medical Corps; mentioned in dispatches for service.
Demobilized and returned to St. Mary's Hospital
Returned to St. Mary's after WWI service and resumed research in the Inoculation Department.
Awarded Hunterian Professorship
Received the Hunterian Professorship from the Royal College of Surgeons (recognition of research contributions).
Noted bacteriolytic activity in his nasal mucus (lysozyme observation)
Notebook entry (21 Nov 1921) records observation of bacteriolytic action from his own nasal secretion that led to identification of lysozyme.
Published discovery of lysozyme
Published 'On a remarkable bacteriolytic element found in tissues and secretions' (Proceedings of the Royal Society B) describing lysozyme.
Birth of son Robert Fleming
Robert Fleming (son) born in 1924; he later became a general medical practitioner.
Elected Professor of Bacteriology, University of London
In 1928 Fleming was elected Professor of Bacteriology at St. Mary's/University of London.
Observed fungal contamination that led to discovery of penicillin
On returning from holiday in September 1928 Fleming noticed a Penicillium-contaminated Staphylococcus plate with a bacteria-free zone; began experiments on 'mould juice'.
Published 1929 paper on antibacterial action of Penicillium cultures
Published his 1929 paper in the British Journal of Experimental Pathology describing penicillin's antibacterial activity.
Arris and Gale Lecturer
Delivered the Arris and Gale lecture in 1929 (honorific lecture appointment).
Presented findings at Medical Research Club (penicillin)
Gave a talk (13 Feb 1929) on his culture work; initial reception was muted and did not lead to immediate development.
Named antibacterial substance 'penicillin'
On 7 March 1929 Fleming gave the name 'penicillin' to the antibacterial substance produced by the Penicillium mould.
First recorded successful medical use of penicillin (Cecil Paine)
Cecil George Paine, using penicillin supplied by Fleming, successfully treated conjunctivitis in one adult and three infants (25 Nov 1930).
Successfully treated severe conjunctivitis
Fleming personally used penicillin ointment to treat a severe conjunctivitis case (often cited as 1932 event).
Florey and Chain begin work at Oxford with Fleming's Penicillium sample
In July 1939 Chain & Florey started research on penicillin using a sample Fleming had provided a decade earlier; led to purification and therapeutic trials.
Early purification of penicillin by Ernst Chain and colleagues
In early 1940 Chain succeeded in purifying penicillin sufficiently to allow animal therapeutic tests (Oxford work building on Fleming's discovery).
Published method to assess penicillin effectiveness
Fleming published a method for assessing penicillin's antimicrobial potency (contributed to its quantification in clinical use).
Treated Harry Lambert with penicillin for streptococcal meningitis
In August 1942 Fleming used an incompletely purified Oxford sample to treat Harry Lambert; the patient recovered.
Elected Fellow of the Royal Society (FRS)
Elected to the Royal Society in recognition of contributions to bacteriology and immunology.
Penicillin Committee formed (UK wartime coordination)
UK Penicillin Committee created 5 April 1943 to coordinate production and supply for Allied forces; Fleming was a member.
Knighted by King George VI
Received knighthood (Knight Bachelor) in 1944 for scientific achievements.
Received multiple honors (John Scott Award, Honorary Fellow RCP)
In 1944 Fleming received the John Scott Award (Philadelphia) and was made an Honorary Fellow of the Royal College of Physicians (London).
Awarded Nobel Prize in Physiology or Medicine (shared)
Shared the 1945 Nobel Prize with Howard Florey and Ernst Chain 'for the discovery of penicillin and its curative effect'.
Delivered Nobel Lecture (after Nobel Prize award)
After receiving the 1945 Nobel Prize, Fleming delivered his Nobel Lecture on 11 December 1945.
Succeeded Almroth Wright as director of the Inoculation Department
Upon Wright's retirement in 1946 Fleming became director; the department was later renamed the Wright-Fleming Institute (1947).
Institute renamed Wright-Fleming Institute
Following Almroth Wright's death the department was renamed the Wright-Fleming Institute in 1947.
Awarded U.S. Medal for Merit and other international prizes
In 1947 Fleming received the U.S. Medal for Merit and several other honors (Gold Medal, Royal Society of Medicine, etc.).
Became Emeritus Professor of Bacteriology, University of London
In 1948 Fleming was appointed Emeritus Professor of Bacteriology (University of London) and reduced active teaching responsibilities.
Death of first wife, Sarah (Sareen) McElroy
Fleming's first wife Sarah (who later styled herself 'Sareen') died in 1949.
Elected Rector of the University of Edinburgh (term 1951–1954)
Served as Rector of the University of Edinburgh for a three-year term starting in 1951.
Married Amalia Koutsouri-Vourekas
Married Dr. Amalia (Amalia Koutsouri-Voureka), a Greek colleague from St. Mary's, on 9 April 1953.
Retired from directorship of the Wright-Fleming Institute
Retired from his directorship in December 1954 but continued to visit the laboratory until his death.
Died of a heart attack in London
Died at his home in London on 11 March 1955; ashes interred in St. Paul's Cathedral.
Posthumous commemorative statue and recognitions begin
Memorials and commemorations began to appear internationally (statues, plaques); general posthumous recognition accelerated in subsequent decades.
Mount Fleming (New Zealand) named
Mount Fleming in New Zealand's Paparoa Range was named in his honour in 1970.
Nobel Prize medal acquired by National Museums of Scotland
Fleming's Nobel Prize medal was acquired by the National Museums of Scotland in 1989 (on display after later re-opening).
Named one of Time magazine's 100 Most Important People of the 20th Century
Time magazine included Fleming on its list of the 100 most important people of the 20th century in 1999.
International Historic Chemical Landmark plaque placed at Fleming Laboratory Museum
On 19 Nov 1999 a plaque recognizing Fleming's discovery was placed at the Alexander Fleming Laboratory Museum in London.
Named among BBC's 100 Greatest Britons
Chosen in the BBC's 2002 television poll for the 100 Greatest Britons.
Image placed on new Clydesdale Bank £5 note
In mid-2009 Fleming's image appeared on the Clydesdale Bank's new £5 banknotes.
Voted third 'greatest Scot' in STV poll
In 2009 an opinion poll by STV ranked Fleming the third 'greatest Scot' behind Robert Burns and William Wallace.
Nobel medal displayed after National Museums of Scotland re-opening
Following museum re-opening in 2011 Fleming's Nobel medal and related exhibits were put on public display.
Portrait mural unveiled in Darvel (commemorative)
In March 2025 a gable-end mural featuring Fleming's portrait was unveiled in Darvel by artist Rogue One.
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