Alexander Fleming: Discoverer Of Penicillin

Story of Alexander Fleming, the discoverer of penicillin, the substance that inhibits the growth of harmful bacteria.

Sir Alexander Fleming was born in 1881 in rural Lochfield, Scotland. He was the seventh of eight siblings and half-siblings. He and his siblings often roamed through the countryside. Of these excursions, Fleming remarked, "We unconsciously learned a great deal from nature." Fleming attended the Polytechnic School and after graduating, worked at a shipping firm. He graduated from the medical school of St. Mary's Hospital in London and began doing immunological research. He was a researcher at St. Mary's throughout his professional career.

In 1909, a chemical treatment for syphilis was developed by the German chemist, Dr. Paul Ehrlich. The chemical was named salvarsan, which means, that which saves by arsenic. Fleming was one of the physicians to use salvarsan, which was injected intravenously. He was so successful with this treatment that he attracted many patients, and received the nickname "Private 606."

During World War I, he was an army doctor and studied wound infections. He observed that antiseptics injured the body cells more than they injured the microbes. He felt that there should be some chemical that could fight microbe infection, such as that found in wounds, which were caused by exploding shells. He realized that a substance was needed that would harm bacteria but would not harm body cells.



In 1928, one of Fleming's staphylococcus bacteria cultures became exposed to the air and became contaminated by a mold. He noticed that the bacteria had been dissolved in the area of the culture surrounding the mold. He believed that the mold had produced a toxic substance that inhibited the growth of harmful bacteria. He named this substance penicillin, after the penicillium notatum mold that it produced. This substance was not toxic to humans or animals. Fleming discovered this substance quite by accident and is quoted as saying, "One sometimes finds what one is not looking for."

In 1929, the results of Fleming's work were published in the British Journal of Experimental Pathology. However, penicillin was not used for more than ten years, because Fleming could not develop a procedure for purifying it. In the late 1930's British medical researchers, Howard Florey and Ernst Chain, read Fleming's article on penicillin. They replicated his work and were able to purify penicillin. After testing it on some patients, they discovered that it was effective.

Pharmaceutical companies in the U.S. and Britain began to produce large quantities of penicillin. At first, it was used only for war casualties, then in 1944, it was made available to civilians. By 1945, penicillin was being used by medical professionals all over the world.

Penicillin is the most widely used antibiotic in the world because it is effective against a variety of harmful microorganisms. It is used to treat scarlet fever, syphilis, diphtheria, bronchitis, meningitis, blood poisoning, pneumonia, and many other ailments. Some people are allergic to penicillin, however, it has a wide margin of safety. Injections of up to 100 million units have been given without any ill effects. Much of the penicillin manufactured is semisynthetic, but all originate from the mold penicillium notatum.

In 1944, Fleming was knighted for his contribution to the field of medicine. He was thereafter known as Sir Alexander Fleming. In 1945, Fleming, along with Florey and Chain, was awarded a Nobel Prize for his discovery of penicillin. Alexander Fleming died in 1955.

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