London, 1928: a group of mold spores surf a breeze through a lab. They drift onto a petri dish, and when they land,
they germinate a medical revolution. This lab belongs to Alexander Fleming, a Scottish scientist
investigating the properties of infectious bacteria. At this time, Fleming is away on vacation.
When he returns, he finds a colony of mold growing on a petri dish he’d forgotten to place in his incubator.
And around this colony of mold is a zone completely and unexpectedly clear of bacteria.
In studying this mysterious phenomenon, Fleming came to realize that the mold was secreting some kind of compound
that was killing the bacteria. The mold was a species in the Penicillium genus,
so Fleming dubbed the antibacterial compound “penicillin.” What Fleming stumbled upon was a microbial defense system.
The penicillium mold constantly produces penicillin in order to defend itself from threats,
such as nearby bacterial colonies that might consume its resources. Penicillin destroys many types of bacteria
