Florey & Chain: Testing and Mass Production
In 1939, Ernst Chain, a biochemist who had fled to Britain from Nazi Germany, came across Alexander Fleming’s published work on penicillin. He was greatly interested, and soon began working on isolating penicillin. Together with lab supervisor Howard Florey, he isolated the antibacterial agent in greater quantity than Fleming had been able to achieve, and then tested the extract by injecting it into two mice which had been infected with a bacterial disease.
The mice recovered, and the two men then tested the penicillin further in a much larger trial run with fifty mice. They subsequently made enough of the substance to use it in two or three people who were dying from bacterial infections. These experiments proved that penicillin would work effectively in humans, but there was a huge stumbling block, in that it was enormously difficult to isolate enough penicillin to treat even one person. With the Second World War underway, the situation was becoming desperate.
Ernst Chain was the driving force behind isolating and testing penicillin, but when it came to manufacturing on a large scale, it was Howard Florey who made more of a contribution, by locating several U.S. companies which were willing to provide resources when U.K. factories were occupied with the war effort.
Mass production of penicillin began, but soon it became clear that the strain of penicillin which Fleming had originally discovered just wasn’t yielding enough of the drug. A hunt for a better source of penicillin ensued, and eventually, in 1943, a lab worker named Mary Hunt provided the goods – a cantaloupe from her own fridge, which was infected with Penicillin chysogeum.
This new mold species produced around 200 times as much penicillin as Fleming’s original discovery, Penicillin notatum. By mutating the species using x-rays, Florey and the U.S. team eventually were able to create a strain of the mold which produced 1,000 times more penicillin as Fleming’s species.
By the end of the war, U.S. companies were making 650 billion units of penicillin every month – staggering in comparison to the 400 units made between January and May 1943.
For their contributions to the discovery and development of penicillin, all three men—Alexander Fleming, Ernst Chain, and Howard Florey—were awarded a Nobel Prize for Medicine in 1945.