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Fleming, Alexander

 

Sir Alexander Fleming

Achievements: Discovered penicillin

Born: August 6, 1881, Lochfield, Ayrshire, Scotland

Died: March 11, 1955, London, England (Aged 73)

Field & Discipline: Science; Medicine; Bacteriology; Immunology

Education: Loudoun Moor School; Dorval School; Kilmarnock Academy; London Polytechnic Institute; St. Mary's Hospital Medical School, London

Major Work: Development of penicillin

Life & Times:

In 1906, Fleming graduated from St. Mary's Hospital Medical School in London and remained permanently with the hospital's bacteriology department.

After graduation Fleming began working (at St. Mary's) in the  laboratory of bacteriologist [worked with] Almroth Wright*, who was committed to the idea that the key to the treatment of bacterial infection and infectious diseases was immunization via vaccine therapy.  In 1909, Fleming became one of the first to treat syphilis with Salvarsan, samples of which had been given to Wright by the German bacteriologist [used drug by] Ehrlich*.  

During World War I Fleming and Wright were sent to Boulogne to tend the wounded who were dying not only of their wounds, but of the deadly infections septicemia, tetanus and gangrene.  Antiseptics appeared not to help.  Fleming made a study of infected wounds, and came to the conclusion that not only were antiseptics powerless against the infections, but also dangerous because they damaged the body cells just as much as the microbes.  Fleming vowed to discover a "magic bullet" that would kill the microbes but leave the body unharmed.

After the War, in 1918 Fleming returned to St. Mary's as a lecturer, and in 1920 was made Director of the Department of Systematic Bacteriology and Assistant Director of the Inoculation Department.  Searching for antibacterial substances that would not be toxic to animal tissues, in 1921 Fleming made what he considered his most important discovery: that mucus from the nose, tears, saliva, other secretions, and even tissues contain a substance that can dissolve certain microbes with remarkable speed. 

Fleming's mentor Wright named this substance "lysozyme," but they found the action of lysozyme on the most pathogenic microbes too weak to be of major use.  However,  the enzyme was proved to help prevent infections, and became a useful research tool for dissolving bacteria for chemical examination.

Through the war years and the 1920’s, Fleming developed methods, still in use, of staining spores and flagella of bacteria.  He identified organisms that cause wound infections, and showed how cross-infection by streptococci can occur among patients in hospital wards. 

He also studied the effects of different antiseptics on various kinds of bacteria and on living cells. 

Fleming's breakthrough came in 1928, by accident.  When a green mold accidentally contaminated some petri dishes containing cultures of the bacterium "Staphylococcus aureus", Fleming (returning after a holiday) studied the reaction.  He noticed that the bacterial colonies around the specks of this mold, which had fallen on the nutrient agar, had disappeared. 

When he cultured the mold in nutrient broth, it formed a felt-like surface layer, which he filtered off.  He then tested the filtrate on a range of bacteria and found that it killed many types of disease-bacteria, even when diluted 800 times.  He identified the mold as "Penicillium notatum", a species related to the mold that grows on stale bread, and named the active substance discharged by the mold the antibiotic (against life) element "penicillin".

Fleming proved that penicillin was nontoxic to animals, even in massive doses, and that it was capable of killing pathogenic microbes with a high level of resistance.  He published his first report on penicillin's antibacterial properties in the "British Journal of Experimental Pathology" in 1929.  Unfortunately, Fleming's chemical knowledge was inadequate to the task of purifying and stabilizing the volatile substance to make it usable in injections in humans, and St. Mary's had no biochemists, so further clinical trials were abandoned.

Throughout the 1930s, Fleming studied the antibacterial properties of sulfonamides, but remained confident that penicillin would eventually be isolated, stabilized and purified.  This was achieved in 1939 by two Oxford scientists, [penicillin work furthered by] Florey* and [penicillin work furthered by] Chain* and their team. 

Their results were published in 1940, and soon afterwards, with mounting casualties in World War II, work began in the United States, Britain, and Canada on the large-scale production of penicillin.  By the end of the War, penicillin had saved many thousands of lives.

Fleming wrote numerous papers on bacteriology, immunology, and [advanced the use of] chemotherapy* during his 40 years at St. Mary's, including original descriptions of lysozyme and penicillin.  Although he and others made countless attempts to reproduce the exact conditions of his first, accidental production of penicillin, he was never able to produce the effect again. (In all probability, a spore of a rare variant "Penicillium notatum" had drifted in from a lab one floor below,  and landed in his Petri dish).  

Between 1945 and 1953 Fleming made a number of speaking tours in the United States and other countries.  However, by this time, Fleming knew that penicillin had an Achilles heel.  He wrote in 1946 that "the administration of too small doses ... leads to the production of resistant strains of bacteria".   This problem endures to this day.

Extra Connections: As a child he met [met] Ehrlich*

His mentor Almroth Wright was wrong about scurvy, which may have helped doom Robert Scott.  Wright was a strong proponent of the Ptomaine theory for the cause of Scurvy.[8] The theory was that poorly preserved meats contained alkaloids that were poisonous to humans when consumed. This theory was prevalent when Robert Falcon Scott planned his fateful expedition to the Antarctic in 1911. In 1932, the true cause of the disease was determined to be the deficiency from the diet of a particular nutrient, now called Vitamin C (Ascorbic acid, Scorbic meaning Scurvy).  More on scurvy

Assessment: An ingenuity in devising experiments, technical skill in implementing them, and uncanny powers of observation led to his two major discoveries: the enzyme lysozyme and the antibiotic penicillin

Oneliner: Alexander Fleming, discoverer of penicillin

Bibliography:

Wikipedia See Node 2

Language: English

Father: Hugh Fleming

Mother: Grace Morton

Siblings: Half-siblings from father's first marriage: Jane; Hugh;  Tom; Mary.  Siblings: Gracie; John; Robert

Spouse: 1) Sarah Marion McElroy; 2) Dr. Amalia Koutsouri-Voureka

Children: Robert (By which wife not known)