tyrothricin

antibiotic

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July 16, 2026

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Tyrothricin is an antibiotic mixture primarily composed of tyrocidine and gramicidin. It is used topically, particularly against gram-positive bacteria. This substance was first discovered in 1940. Tyrothricin was the first antibiotic to be commercially manufactured, following its isolation by René Dubos in 1939 from a soil microorganism. However, it proved too toxic for widespread use. Tyrocidine itself is a basic polypeptide antibiotic produced by a soil bacillus, Bacillus brevis.123

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René Dubos
…antibacterial substance and named it tyrothricin. This substance, which he was able to chemically analyze, became the first antibiotic to be commercially manufactured, though it soon proved too toxic for large-scale use. Dubos’s researches and techniques stimulated interest in penicillin and led Selman Waksman, Albert Schatz, and Elizabeth Bugie to…
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…antibacterial substance and named it tyrothricin. This substance, which he was able to chemically analyze, became the first antibiotic to be commercially manufactured, though it soon proved too toxic for large-scale use. Dubos’s researches and techniques stimulated interest in penicillin and led Selman Waksman, Albert Schatz, and Elizabeth Bugie to…
Read More