Alexander Fleming/Florey and Chain from the Education Forum
Alexander Fleming/Florey and Chain from the Education Forum
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The Story of Penicillin

After Louis Pasteur's and Robert Koch's publications on the germ theory of disease, doctors developed a better understanding of the causes of infection. However, methods of treatment were still limited to vaccinations and anti-toxins. Joseph Lister's carbolic spray worked with some success during operations, but was not suitable for everyday use. The question was, how could people be protected against infection on a day to day basis?
What brought him to prominence?
Fleming was a farmer's son from Ayrshire in Scotland. He moved to London at 13 and later trained as a doctor. In 1928 Fleming was professor of bacteriology at St. Mary's Hospital. He accidentally discovered a mould on a set of culture dishes, which were being used to grow the staphylococci germ (which turns wounds septic). Fleming noticed that where there was mould the germs had stopped developing.

The mould was identified as Penicillium notatum. Fleming subsequently tested this on animals, with no ill effects, and also used it to cure a colleague's eye infection.

How did Florey and Chain aid in this discovery?
Scientists Howard Florey and Ernst Chain developed penicillin further. They were chiefly responsible for the research which brought penicillin into clinical use.

Howard Florey and Ernst Chain decided to develop Fleming's discovery further and set about finding a way to turn the pencillin mould juice into a pure drug, which would be more suitable for the treatment of humans.
Who were Howard Florey and Ernst Chain?
Florey was born in 1898 in Adelaide, Australia. He trained as a doctor and worked on a series of important discoveries at Oxford University. Chain a brilliant Jewish biochemist joined Florey's research team after he fled to Britain from Nazi Germany. Their development of penicillin in the early 1940s led to the award of the Nobel Prize alongside Fleming in 1945.

What are they famous for?
Chain was researching penicillin in 1929 when he read Fleming's article. It was this research which encouraged Florey and Chain to set up a fuller investigation into the drug. In 1940, Florey's team found a way of purifying penicillin which was tested first on mice and then on a patient, a policeman called Albert Alexander. The patient began to recover after receiving the drug, but unfortunately supplies ran out due to their inability to produce it in large quantites. Mass production of the drug was not possible without the help of large drugs companies.

What medical changes were brought about by their discovery?
Florey managed to persuade US drug companies to mass produce penicillin when the US entered the war in December 1941 because it could be used to treat infections caused by war wounds. The US government gave grants to drug companies who wanted to buy the expensive equipment needed to make penicillin. Mass production began in 1943 by British firms. By 1944 there was enough penicillin being produced to supply all the Allied armies. The price of penicillin fell and soon it was being used throughout the world to treat a range of different diseases.

How important was Fleming's discovery?
Fleming had discovered the first antibiotic, however it was not until the research work of Florey and Chain that penicillin could be produced as a drug. At first supplies of penicillin were very limited, but by World War II it was being mass-produced by the American drugs industry, and given to all soldiers before active service.