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The story of penicillin2

Good luck 

One morning in September 1928, six years after the discovery of Lysozyme, Fleming was once again lucky. He was culturing the staphylococcus in a petri dish to observe a variant of the staphylococcus. When the liquid collected from the lesion is smeared on the surface of the "agar medium", which is a solution containing nutrients solidified with agar, the bacteria grow in a few hours and become a round mass of visible size. Form (colony). One colony grows from one bacterium, and if it is collected, pure culture of a specific bacterium becomes possible. 

However, with this method, pollution has been a problem both now and in the past. Bacteria are everywhere, so it's not uncommon for bacteria from somewhere to invade and multiply, overwhelming the cells in culture. 

It happened at this time as well. Penicillium spores jumped from somewhere into one of the petri dishes Fleming was trying to cultivate staphylococci, and were breeding. However, he notices that there are no staphylococci around the penicillium. Fleming's mind passed through the memory of the discovery of Lysozyme. 

He instinctively thought that this might be because Penicillium made some kind of antibacterial substance. "If I hadn't had the experience of lysozyme, I wouldn't have realized the value of this discovery and would have thrown away the medium," he later recalled. 

When I asked a mold expert to identify it, I found that this Penicillium belongs to the genus Penicillium. Fleming takes its name from here and names the antibacterial substance "penicillin". Fleming himself never expected that this would eventually save millions of lives. 

The petri dish, where he first discovered penicillin, was treated to prevent the growth of other fungi and is now on display at the British Museum. Fleming's laboratory has also been recreated in St Mary's Hospital at that time, and has been handed down to the present day. 


The discovery of penicillin would have been due to Fleming's excellent eye, but it's a bit unbelievable that a researcher happens to be blessed with an antibacterial substance twice. .. 

Fortunately, Fleming had been away from his lab for a long time on a family trip from the end of July after finishing staphylococcal culture. Without this period, Penicillium spores might not have jumped into the petri dish and propagated well. 

The mold discovered by Fleming was a rare type of penicillium, and had outstanding penicillin production capacity. Almost the only researcher who knew the reality of the antibacterial phenomenon and its value-in fact, Fleming showed the petri dish to the members of the institute from one end, but who was interested in this strange mold? It's a miraculous probability that he jumped into the place where he didn't seem to be there. 


Dr. Osamu Shimomura, who won the 2008 Nobel Prize in Chemistry for the discovery of GFP (Green Fluorescent Protein), mentioned that this research was a result of various lucks, and this discovery seems to be a heavenly guide. I even wonder if Heaven used me as a human being to give humanity. " Looking at the history of the discovery of penicillin, it is tempting to wonder if this substance was also a benefit that Heaven had given to humankind through Fleming. To that extent, the discovery of penicillin is a combination of good luck and chance. 

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