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The Cure 

By Coralie Ahrenskeaff '24

It is 1928, Dr. Alexander Fleming, a Scottish bacteriologist, is at St. Mary’s Hospital in London bends over a small petri dish, the contents of it yet to be discovered. He seems uninterested, bored even. Sighing, he picks up the petri dish, and walks over to the trash bin to throw it out. Suddenly, he trips on a bit of exposed wire, and a spark falls on Dr. Fleming’s coat. He quickly stands up to shake off the spark, but the petri dish falls, cutting into the exposed wire, providing a way for electricity to wreak havoc over him and the lab. 


Less than 24 hours later, Sarah Marion McElroy, Dr. Alexander Fleming’s wife,  is clutching her four-year- old son Robert by the hand. Her face is tear stained as she stands in her husband’s mangled lab at St. Mary’s Hospital. His body has since been removed from the burn site, relieving her from seeing the remains of her husband of thirteen years. She is told by Dr. Fleming’s assistant that a small incision in a wire brought an electrical fire to the lab. Dr. Fleming had twisted his wrist while trying to break his fall, and was too distracted to notice there was a fire until it was too late.


Following Dr. Fleming's death, McElroy frequently thought back to the story the lab assistant told her of the tragic fire. The assistant mentioned the petri dish Fleming was examining with little interest, and McElroy couldn’t stop thinking about how curious it was how both Fleming and the assistant had so little interest in the uninteresting contents of the petri dish. McElroy, a trained nurse, had been taught never to overlook the smallest details, and with that piece of expertise, along with the terrible loss of her husband, she was driven to do justice to his work. So, one year later, in 1929, a paper was mysteriously published under Dr. Alexander Fleming’s name, titled “On the Antibacterial Action of Cultures of a Penicillium, with Special Reference to their Use in the Isolation of B. influenzæ ''. It was an in-depth examination of mold grown in petri dishes left out in the open air that prevented bacteria from growing around it. McElroy had discovered what turned out to be one of the first antibiotics in a petri dish hidden in Fleming’s personal work desk at home. The general public was under the impression that the paper was written by Fleming before his tragic death, later discovered in some deep dark storage cabinet. Little did she know, despite safely publishing her work under his name, the information she discovered was revolutionary. 


At the time of publishing the report, McElroy and the other women of London had recently gotten the right to vote in 1928, so her fear of being discredited, or denied publication, was understandable. Despite being legally allowed to vote, there was little change in opinion to male superiority. Equal pay legislation was only to be passed about a decade later, in the late 1930s, and single or widowed women were expected to put their children up for adoption, or find a new husband, which was difficult when the woman was already a mother. Because of the discrimination women faced in higher education, and in professions such as law and accounting, McElroy protected herself by publishing under a pseudonym, Dr. Fleming’s name, granting her the liberty to publish without proving herself as a female scientist, but just a scientist. 


Fast forward to 1937, Howard Florey and Ernst Chain discovered “Fleming’s” paper, unaware that McElroy was the brains behind the research. McElroy had been studying at one of the few women’s colleges in England, Somerville, to further her education in chemistry and bacteriology. Unknowingly, her future mentor and lifelong friend, Dorothy Crowfoot Hodgkin, was studying at Somerville in physics and chemistry the same year as McElroy. Equipped with a bachelor's degree in both fields by 1937, McElroy expected her expertise, motivation, intelligence, and community of strong women from Somerville to allow her to work along with the male scientists at The Sir William Dunn School of Pathology in the United Kingdom. Sadly, she was denied access to the Dunn School laboratories because she was a widow and single mother. Somerville administration tried to persuade the scientists to accept McElroy’s work as hers, but still, she was denied access. After three years of fighting for her right to be included in the research, while simultaneously continuing her masters in molecular biology and raising a child, in 1940 McElroy was allowed along with five other women to be a “Penicillin Girl.” Her job was to tend to the breeding sites that provided the sacred milligrams of penicillin produced from the fermented broth.  Although her work was far from being on the forefront of the action, her attention to detail and ability to pick up the smallest pieces of information from passing conversations enabled her to stay up to date with each discovery, revelation, and tweak in the production of what was about to be a revolutionary substance. The Dunn School research furthered the discovery of the mold that stopped bacteria from growing any further and was able to cure four mice with the penicillin they mass produced in their laboratory. McElroy was always a hero but not yet recognized as one. 


As a result of the success found in animal testing done on mice, her male colleagues went on to test penicillin on humans. They expanded their laboratories in Peoria, Illinois, and found a way to produce six times as much penicillin as the laboratory penicillin McElroy took care to cultivate along with the other “Penicilin girls”. No longer working in the sciences because of the financial instability World War II brought to the United Kingdom, she closely followed the information coming out of the Peoria lab. Both Allied and Axis powers were benefiting from the mass production of penicillin. In preparation for D-Day in mid 1944, large pharmaceutical companies in the United States such as Pfizer were working as fast as possible to produce the largest amount of penicillin to save the most lives. Every Allied soldier had a kit that included penicillin on D-Day, saving countless lives. 


In 1945, Florey and Chain won a Nobel prize. McElroy, enraged that after so many years, she was still never mentioned or credited for kickstarting Howard Florey and Ernst Chain’s work, got wind of a Cairo-born, female British chemist named Dorothy Crowfoot Hodgkin who had studied at Somerville the same year as McElroy had. Hodgkin was working at Harvard University with Chain, and disproved a theory regarding the molecular composition of penicillin. Upon hearing that a woman alumni who graduated the same year as she did was working with one of the scientists whom she inspired, McElroy took about a ten-day ship ride from London to Cambridge where Harvard University is located, to meet Hodgkin. McElroy was fascinated by Hodgkin’s work. A leader in X-ray crystallography, she researched the three-dimensional structure of complex organic molecules. Hodgkin inspired McElroy to return to England and to pursue studies at the University of Cambridge, where Hodgkin had received her doctorate in X-ray crystallography. McElroy was lucky to have Hodgkin on her side, vying for her place in the university among the masses of men who did not believe she was smart enough. After five long years of working as a nurse during the day and earning her degree at night, McElroy graduated from the University of Cambridge, and joined Hodgkin and her team of scientists who were working to prove the structure of vitamin  B-12 and insulin. The two of them discovered the structure of vitamin B-12, the most complex molecule, winning them a Nobel prize in 1964. They became the fourth and fifth women ever to win a Nobel Prize. It was awarded “to the joint effort in discovering the complexity of vitamin B-12 and penicillin”. McElroy died in 1965, proud of her achievements and knowing her persistence led to the saving of countless lives. 

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