In 1922, Fleming discovered enzyme lysozyme, the "body's own antibiotic", and that it has a weak anti-bacterial property ("Sir Alexander Fleming...").
In September 1928, while working on influenza virus, he observed that mould had developed accidently on a staphylococcus culture plate and that the mould had created a bacteria-free circle around itself. He was inspired to further experiment and he found that a mould culture prevented growth of staphylococci, even when diluted 800 times. He named the active substance penicillin ("Alexander Flemming").
How does this affect me?
Penicillin is important in today's society because it is used as a treatment against different types of infectious diseases and infections. Infected people all over the world have been saved because of penicillin.
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