Application:
• Florey and Chain’s experiments to test penicillin on bacterial infections in mice
The first chemical compound found to have antibiotic properties was penicillin, which was identified by Alexander Fleming in 1928
- The discovery of penicillin was a fortuitous accident, resulting from the unintended contamination of a dish containing S. aureus
- A Penicillium mould began to grow on the plate and a halo of inhibited bacterial growth was observed around the mould
- Fleming concluded that the mould was releasing a substance (penicillin) that was killing the nearby bacteria
The Discovery of Penicillin
Medical Applications
The medical applications of penicillin as an antibiotic were demonstrated by an Australian scientist, Sir Howard Florey, in 1940
- Working with another scientist (Ernst Chain) and a team of researchers, Florey tested penicillin on infected mice
- Eight mice were injected with hemolytic streptococci and four of these mice were subsequently injected with doses of penicillin
- The untreated mice died of bacterial infection while those treated with penicillin all survived – demonstrating its antibiotic potential
Florey and Chain Experiment
Historical Significance
In 1945, Howard Florey, Ernst Chain and Alexander Fleming were collectively awarded the Nobel Prize for Medicine
- Following the chemical determination of penicillin structure in 1945, several synthetic derivatives have since been created
- These derivatives (including methicillin) offer many benefits including a broader spectrum, more stability and greater tolerance
Nobel Laureates (Medicine – 1945)
