“Flem’s mouldy fluid”

Posted in Discoveries, Historical articles, Medicine on Saturday, 9 September 2017

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Alexander Fleming, picture, image, illustration

Alexander Fleming in his laboratory

In 1928 a Scottish doctor named Alexander Fleming was growing bacteria for investigation in little glass dishes in a room in his hospital by Paddington railway station in London. Microscopic mould spores drifted in through the window and settled in one of the dishes while the lid was off it for examination. Round where the mould grew in the dish, the bacteria appeared to be killed off.

The dishes in which bacteria were cultured often became spoiled or contaminated, and would then be thrown away as useless. But in this case Fleming, in a historic moment of curiosity and fortune, decided to cultivate the mould and investigate it. He found it was producing a substance which attacked bacteria. The substance he named penicillin (after the scientific name of the mould). Thus was discovered one of the most powerful drugs that man has ever found.

But it was another 13 years before penicillin was produced in a way which could be used to cure disease.

Back in the 1920s, there were two ways of treating infections. One was by vaccination: this assists the body’s natural defence against bacteria to fight off an infection. This method is known as immunisation, and though of great value for certain diseases, its effectiveness is limited.

The other way was by killing the germs with antiseptics, such as carbolic acid. But antiseptics are poisonous if swallowed, so they can only be used to kill germs on the surface of the body or outside it.

The idea of another way of treating infections had been pioneered by a great German doctor named Paul Ehrlich around the beginning of the century. Ehrlich saw that the perfect cure for infections would be a chemical substance which would destroy the harmful microbes invading the body without injuring anything else.

“Such substances,” he said, “would be magic bullets which are aimed only at the foreign intruder in the body and do not touch the body’s own cells.”

But the search for chemical substances which would seek out and attack a germ within the living body without harmful effects on the patient had little success during the following years. When Fleming discovered penicillin in 1928, most people in medicine assumed that the “magic bullets” foreseen by Ehrlich were not a realistic prospect.

Fleming’s discovery went largely unnoticed at the time. Though he was a superb laboratory worker, he lacked the resources to purify the germ-destroying substance which he had found, or to produce it in a form which would be useful in medicine. His preparations of it lost their effects very quickly and were referred to by the people working around him as “Flem’s Mouldy Fluid”. No one realised that in this “Mouldy Fluid” Fleming had in his hand a magic bullet against the forces of microbes infecting the body which was to be more effective than any doctor dared to dream of.

Alexander Fleming was 47 years old when he discovered penicillin. He was the son of a small Scottish farmer. He left school at 14 and went to London. For four years he worked as a shipping clerk, and saved enough money – supplemented by a small legacy – to study at medical school and become a doctor at St. Mary’s Hospital in Paddington, London. By 1928 he was Professor of Bacteriology at St. Mary’s.

The old building of St. Mary’s Hospital still stands, and the window of Fleming’s room through which spores of that famous growth of mould are supposed to have come can be seen above the pavement of Praed Street. The laboratory in which penicillin was discovered was small and dingy and crowded; had Fleming been better accommodated his dish would probably never have been contaminated.

Two years after Fleming’s discovery, two scientists at Oxford University “rediscovered” Fleming’s work on penicillin and took up work on it again. They succeeded in purifying it and producing it in a stable form. On 12th February, 1941, they were able to treat their first human patient.

The problem now was one of production. The yields of penicillin from the methods used were pitifully low. The Second World War was in progress. Here was the most life-saving drug in the world, but supplies of it were limited.

The Oxford scientists visited the United States to persuade the Americans to undertake research and development to produce penicillin on a large scale. A massive effort was mounted in the United States to this end, involving an enormous concentration of brain-power from hundreds of scientists and technologists and a vast expenditure of money. The great technological breakthrough came in 1943, when a new process enabled penicillin to be produced from deep fermentation in gigantic vats.

The two Oxford scientists were Howard Florey and Ernest Chain. Theirs is another story, and they also have their claim to greatness. In 1945, Fleming, Florey and Chain were jointly awarded the highest honour in science, the Nobel Prize. Fleming was knighted by King George VI in 1944, and Florey and Chain subsequently; Florey was also later to receive a peerage.

Alec Fleming died in 1955, and was buried in the crypt of St. Paul’s Cathedral near the tombs of Nelson and Wellington.

Penicillin became generally available in 1946, after the war. In the five following years, medicine was to be transformed by pencillin and similar drugs. New drugs were quickly found to deal with other microbes which penicillin did not destroy, so that doctors now have chemical weapons to attack most infectious diseases which are caused by bacteria.

This edited article about medicine originally appeared in Look and Learn issue number 849 published on 22 April 1978.

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