What new insights have emerged about penicillin’s discovery after 75+ years?
The main new insight is a hidden chapter: Dutch scientists secretly made their own penicillin during World War II, under German occupation. Records of that work only came to light in the 10 to 15 years before this 2017 paper. The Dutch company began selling its penicillin in 1946, which raised the supply and lowered the price. The paper also retells the familiar story, and it confirms that Fleming’s 1928 discovery began with a chance event.
This is a short history essay by infectious disease physician Robert Gaynes, published in Emerging Infectious Diseases. It follows penicillin from Fleming’s moldy plate to mass production, then adds the newer material from wartime Europe.
Dr. Kumar’s Take
This paper adds a chapter most people never hear. The usual story ends with Oxford and American drug companies. The Dutch team started with nothing but Fleming’s 1929 paper and, later, a smuggled Swiss medical journal. They worked under a German guard and still made the drug.
The paper also reinforces something I agree with. Penicillin’s discovery depended on a rare string of lucky breaks. That is a strong reason to use today’s antibiotics with care, because new ones are hard to find.
From a Chance Observation to a Drug
In 1928, Alexander Fleming returned from vacation to his London lab and noticed a zone around a stray mold where bacteria did not grow. He identified the mold as a Penicillium species, named its active agent penicillin, and showed it worked against staphylococci and other bacteria. He published in 1929. But he could not purify the unstable compound, and for about a decade there was no progress.
The success of sulfa drugs in the mid-1930s revived interest in drugs that kill bacteria. At Oxford, Howard Florey, Ernst Chain, and Norman Heatley purified penicillin. In a key experiment, 8 mice were infected with strep bacteria and 4 were given penicillin. By the next morning, all 4 untreated mice were dead and all 4 treated mice were alive.
In February 1941, an Oxford policeman with a severe infection became the first person treated. He improved within 24 hours, but the supply ran out and he died a few weeks later. Other patients did well.
How the United States Scaled It Up
British companies could not mass produce penicillin during the war, so Florey and Heatley went to a US Department of Agriculture lab in Peoria, Illinois. Two changes made the difference. Growing the mold in corn steep liquor, a waste product of cornstarch making, gave far higher yields. A strain found on a moldy cantaloupe made 6 times more penicillin than Fleming’s. Drug companies then developed deep-tank fermentation.
The results were dramatic. In 1941, the US did not have enough penicillin to treat a single patient. By the end of 1942 there was enough for fewer than 100 patients. By September 1943 there was enough to meet the needs of the Allied armed forces.
The Fleming Myth
In 1942, Fleming used some of Oxford’s supply to cure a patient dying of streptococcal meningitis. A major article in The Times named Oxford as the source of the penicillin but did not mention Fleming or Florey. Fleming’s boss, Sir Almroth Wright, quickly wrote to The Times praising Fleming’s work. Fleming talked to reporters, while Florey barred his team from giving interviews. Many people came to believe Fleming alone was responsible for penicillin.
Secret Penicillin in Occupied Europe
Britain tried to keep penicillin production out of enemy hands. But Fleming had mailed his mold to labs all over the world.
- France: The Institut Pasteur and Rhone-Poulenc began work in 1942. When the Germans asked for their strain, the French handed over one that made no penicillin. France produced enough to treat about 30 patients before the war ended.
- The Netherlands: A Dutch fungus collection near Utrecht had Fleming’s strain. When the Nazis asked for it in 1942, the director, Johanna Westerdijk, sent a strain that made no penicillin. In 1944 she sent her strains to a yeast and spirits company in Delft, NG&SF.
- Code name Bacinol: The Delft scientists called their product Bacinol to hide what it was. They grew the mold in milk bottles and kept their German guard supplied with gin so he slept most afternoons. They produced it from July 1944 until March 1945. Only after the war did they confirm it was the same compound as English penicillin.
- Germany did make penicillin by October 1944, but Allied air raids crippled mass production.
Because the Dutch used their own mold and their own methods, they avoided the patent fights that followed the war. Their penicillin went on sale in January 1946 and helped increase supply and bring prices down.
Fleming, Chain, and Florey shared the 1945 Nobel Prize in Physiology or Medicine.
Practical Takeaways
- Breakthroughs can hinge on luck: Penicillin’s discovery depended on a string of chance events, which is one reason new antibiotics are hard to find.
- Credit is often shared: Oxford, US government labs, drug companies, and a secret Dutch team all made penicillin possible, not Fleming alone.
- Partnerships work: The author points to the wartime public and private cooperation as a model for finding new antibiotics.
- Resistance is the modern threat: Antibiotics lose power with heavy use, and many drug companies have nearly stopped searching for new ones.
Related Studies and Research
- Penicillin: The Accidental Discovery That Changed Medicine and Won a War
- On the Antibacterial Action of Cultures of Penicillium
- Penicillin: The Oxford Story
- Penicillins Discovery and Antibiotic Resistance: Lessons for the Future
FAQs
Was Fleming’s discovery really accidental?
Largely, yes. The paper calls it a chance event and quotes biographer Gwyn Macfarlane, who described it as “a series of chance events of almost unbelievable improbability.” Fleming did recognize what he saw, identified the mold, and tested it against bacteria. But he could not purify it, and it took the Oxford team about a decade later to turn it into a drug.
What new insights have emerged about penicillin’s mechanism?
The new insights in this paper are historical rather than about how the drug works. They center on secret wartime penicillin production in the Netherlands and France, which only came to light in the 10 to 15 years before the paper.
How has our understanding of the development process changed?
It took many hands. Oxford purified and tested it, US government labs and drug companies scaled it up, and Dutch scientists built their own process in secret. Fleming got most of the public credit partly because he spoke to the press while Florey kept his team from giving interviews.
What does this mean for current antibiotic research?
The author draws two lessons. Public and private partners working together made penicillin production succeed, and that model could help find new antibiotics. And because bacteria become resistant with heavy use, while many drug companies have nearly abandoned new antibiotic discovery, existing antibiotics need to be used carefully.
Bottom Line
Penicillin began with a chance observation in Fleming’s lab in 1928, but it took Oxford scientists, American labs and drug companies, and wartime cooperation to turn it into a medicine. The newer insight in this 2017 paper is that Dutch scientists secretly made their own penicillin under German occupation and began selling it in 1946, which increased supply and lowered prices. The author’s closing point is practical: antibiotics this hard to find deserve careful use.
