Fleming · Penicillin
What can a contaminated dish reveal?
That time, that place
Fleming left for holiday without clearing the culture dishes stacked on his bench. He returned to find mold growing on one of them.
Around the mold lay a clear ring where the bacteria had not grown.
Why this question
The mold landing on the dish was chance. Recognizing the ring was not.
Years earlier Fleming had dripped his own nasal mucus onto a culture while he had a cold, watched the bacteria die, and discovered lysozyme. He already had eyes for this.
What was found
He named the substance the mold released penicillin and published.
There he stalled. He could not purify it, and what he did extract lost its potency quickly. It could not be made into a medicine.
The paper attracted almost no attention and sat for a decade.
A bacterial infection was something the body had to defeat on its own
A clear ring around the mold where bacteria would not grow
In 1939 Florey and Chain at Oxford managed to purify it, and American industry worked out mass production in time to save wounded soldiers. In his Nobel lecture Fleming warned that careless use would breed resistance