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Alexander Fleming's penicillin mold

Alexander Fleming's penicillin mold

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In September 1928, British bacteriologist Alexander Fleming found something unusual growing in his laboratory. Mold had contaminated a plate of Staphylococci, disease-causing bacteria. Where the mold had spread, the bacteria had disappeared.
Further research revealed that the mold, Penicillium notatum, produced a substance harmful to microorganisms but relatively nontoxic to animals and humans. During World War II, British and American scientists expanded on Fleming's discovery to develop the powerful antibiotic penicillin.
Object Name
Penicillin Mold
Date made
ca. 1940
date made
Mold produced in 1928, mounted ca 1940
Fleming, Alexander
Fleming, Alexander
place made
United Kingdom: England, London
overall: 2 in x 2 in x 1/2 in x 2 in; 5.08 cm x 5.08 cm x 1.27 cm x 5.08 cm
ID Number
accession number
catalog number
Credit Line
Pfizer, Inc.
See more items in
Medicine and Science: Medicine
Data Source
National Museum of American History
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