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The Greatest Little Paintbrush Ever

On August 6, 1881, doctor and bacteriologist Sir Alexander Fleming was born. As a doctor in the British Army Medical Corps (WWI), Fleming relied on his own skills in titration, the continuous measurement and adjustment in balancing a medication or treatment. He noticed that the treatment of wounds and infections with antiseptic caused more harm than good. A gifted observer who was tenacious in following up on his observations, he soon established wound cleansing with a saline solution.

After the war, and concerned with infections and incorrectly prescribed and administered medications, Fleming focused on searching for substances that would destroy infectious bacteria without destroying body tissue or compromising body defenses. Noting the antibacterial action of nasal mucus on bacterial cultures, he investigated to determine what active substance was responsible. He discovered it to be an enzyme he called lysozyme, a word Fleming created from the Greek lysein [within] and zyme [ferment]. He had identified one of the natural defenses against infections in humans.

A few years later, he returned from a vacation to find a mould spore had infected a poorly sealed culture of staphylococci. The bacteria had grown all over the medium except in a clear circle around the spore. As with his careful notice and exploration of lysozyme, Fleming paid attention. The spore of Penicillium, a genus of fungi, not only kept the bacteria from encroaching but also dissolved the bacteria that came into contact with it. Trying to manage it in a useful delivery agent, Fleming found that the brush-shaped mould maintained its antibacterial properties even when diluted up to 1 part in 1,000! He named it penicillin, from the Greek penicillus [paintbrush]. He had launched the modern era of antibiotic discovery.

Sir Alexander Fleming views his antibacterial paintbrush, penicillin
Sir Alexander Fleming views his antibacterial paintbrush, penicillin

Fleming received a knighthood for his discovery. He published his findings and presented them to other researchers, chemists, and bacteriologists. It took almost ten years and the demands of another World War before penicillin would be produced in a purified, concentrated, and usable form. These researchers/investigators became Nobel laureates with Fleming.

Fleming lived to see penicillin mass-produced to help millions. He encouraged other researchers to experiment with its structure and chemistry to produce strains that removed disadvantages of the antibiotic. Fleming was especially concerned with and constantly warned against the danger he saw in using incorrect dosages – specifically in underdosing or curtailing a course of penicillin since an original dose might be only enough to contain, but not sufficient to kill, the bacteria being treated. This could lead to the bacteria learning to become resistant to further dosing. When the dose fails; the bacteria win.

Fleming’s likeness is found on banknotes, stamps, and statuary and his name memorialized on schools, colleges, science and university buildings around the world.

B Bondar / Real World Content Advantage