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153

penicillin

OLogy Series
biology
card
153

penicillin

OLogy Series
biology

Just a century ago, many people died from minor bacterial infections and diseases. A simple cut or strep throat could be fatal. But today, we have antibiotics that protect people from infections by killing harmful bacteria. The first of these life-saving antibiotics was penicillin, made from a type of mold that grows naturally. This "miracle drug" changed medicine forever.

A Mold to the Rescue!
During World War I, Alexander Fleming saw many soldiers die from the bacterial infections in their wounds. The young doctor returned from the war determined to find a chemical to kill harmful bacteria. But his famous discovery in a London hospital was actually an accident. One day in 1928, while cleaning his laboratory, he found mold growing in a petri dish. The unexpected mold had killed all the bacteria around it. He took a sample of the mold and found that it was from the penicillium family. Fleming published his findings but wasn't able to turn penicillin into a drug. Then, in 1935, Oxford scientists Howard Florey and Ernst Chain expanded on Fleming's work and used penicillin to successfully treat mice, then humans. When World War II began, the research was moved to the United States. Soon scientists were able to produce large enough quantities to treat wounded soldiers and save thousands of lives. Fleming's dream had come true. In 1945, Fleming, Florey, and Chain were awarded the Nobel Prize for Medicine.

Penicillin kills harmful bacteria by:

destroying their cell walls

injecting poisonous chemicals into them

suffocating the bacteria so they can't get nutrients

Are you right?

Correct!

Penicillin works by destroying the cell walls of the bacteria, making it impossible for the bacteria to reproduce and survive.

The discovery of penicillin marked the first time a fungus was used to treat infections.

Fact
or
Fiction
?

Fiction

They may not have recognized fungi as the real remedy, but many ancient cultures used fungi to treat infections. Ancient Chinese put moldy soybeans on skin infections.

If you're taking antibiotics for an infection, you don't have to finish them if you start to feel better.

Fact
or
Fiction
?

Fiction

It's important to take ALL of your prescribed antibiotics. If you don't, then some bacteria can survive, causing another infection.

penicillin
Scientific name of mold: Penicillium notatum
Discovered by: Alexander Fleming, 1928
Where it grows: naturally occurring mold; needs a lot of air to grow
How it works: kills by stopping bacteria from making new cell walls
Significance: prior to discovery, many people died from simple cuts or minor infections

Image credits: Eric Hamilton.