A Science Odyssey
People and Discoveries

Alexander Fleming
1881 - 1955

Alexander Fleming was born in a remote, rural part of Scotland. The seventh of eight siblings and half-siblings, his family worked an 800-acre farm a mile from the nearest house. The Fleming children spent much of their of time ranging through the streams, valleys, and moors of the countryside. "We unconsciously learned a great deal from nature," said Fleming.

When their father died, Fleming's eldest brother inherited the running of the farm. Another brother Tom had studied medicine and was opening a practice in London. Soon, four Fleming brothers and a sister were living together in London. Alec, as he was called, had moved to London when he was about 14, and went to the Polytechnic School in Regent Street. Tom encouraged him to enter business. After completing school he was employed by a shipping firm, though he didn't much like it. In 1900, when the Boer War broke out between the United Kingdom and its colonies in southern Africa, Alec and two brothers joined a Scottish regiment. This turned out to be as much a sporting club as anything; they honed their shooting, swimming, and even water polo skills, but never went to the Transvaal. Soon after this, the Flemings' uncle died and left them each 250 pounds. Tom's medical practice was now thriving and he encouraged Alec to put his legacy toward the study of medicine.

Fleming took top scores in the qualifying examinations, and had his choice of medical schools. He lived equally close to three different schools, and knowing little about them, chose St. Mary's because he had played water polo against them. In 1905 he found himself specializing as a surgeon for almost as random a reason. His switch to bacteriology was even more surprising: if he took a position as a surgeon, he would have to leave St. Mary's. The captain of St. Mary's rifle club knew that and was desperate to improve his team. Knowing that Fleming was a great shot he did all he could to keep him at St. Mary's. He worked in the Inoculation Service and he convinced Fleming to join his department in order to work with its brilliant director -- and to join the rifle club. Fleming would stay at St. Mary's for the rest of his career.

In 1909 German chemist-physician Paul Ehrlich developed a chemical treatment for syphilis. He had tried hundreds of compounds, and the six hundred and sixth worked. It was named salvarsan (meaning "that which saves by arsenic"). The only previous treatments for this disease had been so toxic as to often kill the patient. Ehrlich brought news of his treatment to London, where Fleming became one very few physicians to administer salvarsan. He did so with the new and difficult technique of intravenous injection. He soon developed such a busy practice he got the nickname "Private 606."

When World War I broke out, most of the staff of the bacteriology lab went to France to set up a battlefield hospital lab. Here they encountered infections so drastic that soldiers quickly died from them. Yet they were still simple infections. Fleming felt there must be something, a chemical like salvarsan, that could help fight microbe infection even in wounds caused by exploding shells. During the course of the war, Fleming made many innovations in treatment of the wounded, but this was soon overshadowed by the work he did afterwards.

Back in St. Mary's lab in the 1920s, Fleming searched for an effective antiseptic. He discovered lysozyme, an enzyme occurring in many body fluids, such as tears. It had a natural antibacterial effect, but not against the strongest infectious agents. He kept looking. Fleming had so much going on in his lab that it was often in a jumble. This disorder proved very fortunate. In 1928 he was straightening up a pile of Petri dishes where he had been growing bacteria, but which had been piled in the sink. He opened each one and examined it before tossing it into the cleaning solution. One made him stop and say, "That's funny." Some mold was growing on one of the dishes -- not too unusual -- but all around the mold, the staph bacteria had been killed -- very unusual. He took a sample of the mold. He found that it was from the penicillium family, later specified as penicillium notatum. Fleming presented his findings in 1929, but raised little interest. He published a report on penicillin and its potential uses in the British Journal of Experimental Pathology. Fleming worked with the mold for some time, but refining and growing it was a difficult process better suited to chemists. The work was taken over by a team of chemists and mold specialists, but was cut short when several of them died or relocated. It took World War II to revitalize interest in penicillin, and Howard Florey and Ernst Chain picked up the work.

In recognition for his contribution, Alexander Fleming was knighted in 1944. With Chain and Florey he was awarded the Nobel Prize in 1945.

"One sometimes finds what one is not looking for."

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