It wasn't until the late C19th that scientific studies of anti-biotics began. French chemist Louis Pasteur discovered that infectious diseases spread by bacteria; he observed that mould inhibited the growth of an infectious animal disease, anthrax. British surgeon Joseph Lister noted that samples of urine contaminated with mould didn't allow bacteria to grow, but he couldn't identify the substance in the mould. French medical student Ernest Duchesne successfully tested a substance from mould that inhibited bacterial growth in animals, but he died in 1912.
After WW1, Scottish scientist Alexander Fleming (1881–1955) was working at St Mary's Hospital in London. While conducting an experiment with bacteria, a tear fell from his eye into a Petri dish. He later noticed that a substance in his tear killed the bacteria, but was harmless to the body's white blood cells.
Years later, in 1928, Fleming was doing research on the flu. While he was away on holidays, some mould fell into a discarded Petri dish containing bacteria. When this messy scientist returned to his lab, he recognised the pattern from his previous experience. The mould was producing an antibiotic substance that he named Penicillin.
Thus the first antibiotic used successfully to treat people with serious infectious diseases began with dumb luck. Bacteria reproduce by dividing into two new cells. They enlarge their size before the DNA chromosome is copied. The two new chromosomes move apart and a cell wall forms between them. But if there’s penicillin, the new cell wall won't be able to form and the bacteria can't reproduce, so the disease can't spread. Fleming noticed that mould had prevented the growth of bacteria in his lab but he couldn't extract the bacteria-killing substance. He wrote up his findings in the British J of Experimental Pathology (1929), got a cool response and moved on to other research.
So the main plot of the story involves the re-discovery of penicillin 10 years later by an Australian scientist Howard Florey (1898-1968). Florey had been brilliant at school and sport, and studied Medicine at Adelaide Uni. He won a Rhodes Scholarship and went to Oxford University in 1921.
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However, several strains of bacteria became resistant to penicillin after a few years, through mutation of the cells. To overcome this, 1950s scientists made artificial penicillin by chemically changing natural penicillin; resistant bacteria multiply when non-resistant bacteria die. Hospitals in Australia etc saw the arrival of antibiotic-resistant bacteria due to the _overuse_ of antibiotics.
Fleming’s role as the leader of the scientists that developed penicillin won him the Nobel Prize in 1945 with Florey and Chain. He was knighted in 1944. He was the first Australian elected to the prestigious position of President of the Royal Society in 1960.
Penicillin G is the form that killed bacteria during Duchesne's work in 1896, Fleming in 1928 and Florey in 1939. There are now 60+ antibiotics, substances that fight bacteria and other microbes harmful to humans. Everybody knows of Alexander Fleming’s role in discovering penicillin. Alas Howard Florey’s vital role in the story is still largely unknown.
I thank and recommend The Discovery of Penicillin by Robert Gaynes and Sandwalk by Prof Moran.
After WW1, Scottish scientist Alexander Fleming (1881–1955) was working at St Mary's Hospital in London. While conducting an experiment with bacteria, a tear fell from his eye into a Petri dish. He later noticed that a substance in his tear killed the bacteria, but was harmless to the body's white blood cells.
Years later, in 1928, Fleming was doing research on the flu. While he was away on holidays, some mould fell into a discarded Petri dish containing bacteria. When this messy scientist returned to his lab, he recognised the pattern from his previous experience. The mould was producing an antibiotic substance that he named Penicillin.
Thus the first antibiotic used successfully to treat people with serious infectious diseases began with dumb luck. Bacteria reproduce by dividing into two new cells. They enlarge their size before the DNA chromosome is copied. The two new chromosomes move apart and a cell wall forms between them. But if there’s penicillin, the new cell wall won't be able to form and the bacteria can't reproduce, so the disease can't spread. Fleming noticed that mould had prevented the growth of bacteria in his lab but he couldn't extract the bacteria-killing substance. He wrote up his findings in the British J of Experimental Pathology (1929), got a cool response and moved on to other research.
So the main plot of the story involves the re-discovery of penicillin 10 years later by an Australian scientist Howard Florey (1898-1968). Florey had been brilliant at school and sport, and studied Medicine at Adelaide Uni. He won a Rhodes Scholarship and went to Oxford University in 1921.
photo credit: Sandwalk
Florey gathered a team of specialist scientists at Oxford Uni in 1938. They commenced a careful investigation of the properties of anti-bacterial substances that are produced by mould. German scientist Ernst Chain worked on purifying penicillin with Edward Abraham. Norman Heatley improvised methods for extracting penicillin using ether and bedpans. AD Gardner and Jena Orr-Ewing studied how penicillin reacted with other organisms. Howard Florey looked with Margaret Jennings at the impact of penicillin on animals. Ethel Florey later worked with her husband on clinical trials of penicillin. Individual members worked separately then got together to exchange ideas.
By May 1940 the work was urgent, so Florey's team tested penicillin on eight mice injected with a lethal dose of streptococci bacteria. Four of the mice were treated with penicillin, while four weren’t. Next day, the treated mice had recovered; the other mice were dead.
The results were so exciting Florey knew it was time to test the drug on humans. The first patient in 1941 had a terrible infection and was given penicillin, and soon began to recover. But because Florey's team didn't have enough of the drug to see the patient through to a full recovery, the patient died. Instead the team concentrated on sick children, who required smaller quantities.
In 1943 Florey travelled to North Africa to test the effects of penicillin on wounded soldiers. Instead of amputating wounded limbs, the wounds were cleaned and sewn up, and the patients given penicillin.
Florey's team worked with a lack of funding and equipment, and needed drug companies to help produce the large amounts required. Companies in Britain were unable to help out on a large scale because of the war, so Florey and Heatley took a dangerous flight to the USA in a blackened plane. The trip was against the wishes of Ernst Chain, who wanted to first patent their ideas in Britain. This would have made the team very rich, but patenting medical discoveries in Britain that had used government funding would have been unethical.
Florey explained his penicillin-making methods in the USA, including in a Department of Agriculture laboratory looking for a new use for a by-product of the corn-milling process. When this liquid was used, 10 times the amount of penicillin was able to be produced. Then they found mould growing in cantaloupe was twice as successful again. By late 1943 mass production of the drug had commenced, a sign of Florey's persistence and determination. Thanks to his team, the drug was available to treat Allied troops by D-Day 1944.
By the end of the war, many laboratories were making the drug eg Merck, Squibb and Pfizer Cos in the USA and the Commonwealth Serum Laboratories in Australia. CSL made the drug available for civilian use.
The results were so exciting Florey knew it was time to test the drug on humans. The first patient in 1941 had a terrible infection and was given penicillin, and soon began to recover. But because Florey's team didn't have enough of the drug to see the patient through to a full recovery, the patient died. Instead the team concentrated on sick children, who required smaller quantities.
In 1943 Florey travelled to North Africa to test the effects of penicillin on wounded soldiers. Instead of amputating wounded limbs, the wounds were cleaned and sewn up, and the patients given penicillin.
Florey's team worked with a lack of funding and equipment, and needed drug companies to help produce the large amounts required. Companies in Britain were unable to help out on a large scale because of the war, so Florey and Heatley took a dangerous flight to the USA in a blackened plane. The trip was against the wishes of Ernst Chain, who wanted to first patent their ideas in Britain. This would have made the team very rich, but patenting medical discoveries in Britain that had used government funding would have been unethical.
Florey explained his penicillin-making methods in the USA, including in a Department of Agriculture laboratory looking for a new use for a by-product of the corn-milling process. When this liquid was used, 10 times the amount of penicillin was able to be produced. Then they found mould growing in cantaloupe was twice as successful again. By late 1943 mass production of the drug had commenced, a sign of Florey's persistence and determination. Thanks to his team, the drug was available to treat Allied troops by D-Day 1944.
By the end of the war, many laboratories were making the drug eg Merck, Squibb and Pfizer Cos in the USA and the Commonwealth Serum Laboratories in Australia. CSL made the drug available for civilian use.
The Discovery and Development of Penicillin 1928-1945,
commemorative booklet of the National Historic Chemical Landmarks programme
American Chemical Society, 1999.
Fleming’s role as the leader of the scientists that developed penicillin won him the Nobel Prize in 1945 with Florey and Chain. He was knighted in 1944. He was the first Australian elected to the prestigious position of President of the Royal Society in 1960.
Penicillin G is the form that killed bacteria during Duchesne's work in 1896, Fleming in 1928 and Florey in 1939. There are now 60+ antibiotics, substances that fight bacteria and other microbes harmful to humans. Everybody knows of Alexander Fleming’s role in discovering penicillin. Alas Howard Florey’s vital role in the story is still largely unknown.
I thank and recommend The Discovery of Penicillin by Robert Gaynes and Sandwalk by Prof Moran.