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Alex Rovner
Benton
2B
15 December 2011
The Discovery of Penicillin and How it Contributed to the Advancement of Antibiotics
Because of the invention of antibiotics, many diseases that were previously untreatable
became possible to cure, and the rate of death from infectious disease considerably lessened.
Previous to antibiotics, many people suffered from horrible diseases that would shorten their life
by a significant amount. Some examples of these awful diseases are small pox, tuberculosis, and
pneumonia, which all almost always resulted in death. The invention of antibiotics helped solve
this problem by being able to cure some diseases and giving hope to other sufferers. The
invention of many antibiotics, including penicillin, revolutionized medicine by helping cure
bacterial diseases, whether deadly or not, and starting a whole new era in the evolution of
medicine.
Calvo (373) states that Alexander Fleming was experimenting with staphylococcus when
one of his petri dishes was contaminated with Penicillium notatum, a species of mold.
Surrounding the mold there was a ring where no bacteria grew, and Fleming concluded that the
mold secreted a substance that caused this pattern. He called the substance Penicillin. Alexander
Fleming accidentally came across the first penicillin by accident when he came back from a
vacation and realized that one of his petri dishes had been contaminated with a species of
bacteria and mold (B. Lerner and K. Lerner 276). The mold caused the bacteria to turn
transparent and lyse. He named Penicillin after the mold, Penicillium. According to Woolf (245),
after leaving a petri dish for a few days, Alexander Fleming came back to it to find that there was
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a new mold spore with a colony of bacteria growing on it. He observed that the bacteria on top of
the mold had become transparent while the bacteria not on the mold had continued to grow. He
concluded that the mold was an antibiotic. Penicillin was thus discovered by Alexander Fleming
after he discovered a petri dish that was not sanitized. It contained a mold that repelled bacteria.
Woolf (245-252) states that even when the penicillin was diluted from 500 to 800 times,
its effectiveness was still very strong. Penicillin works by stopping bacteria’s cell walls from
working, eventually killing the bacteria over time. One problem, though, is that it does not threat
several kinds of infections including the common cold, whooping cough, and tuberculosis.
According to Calvo (373), Fleming diluted the substance (penicillin) hundreds of times and it
still was effective. Penicillin also did not destroy white blood cells like other antiseptics did. He
injected it into animals and it proved to not have negative effects. The development of antibiotics
has cured almost all bacterial infectious diseases that were incurable prior to their development
(B. Lerner and K. Lerner 276). The rate of death of bacterial infection in the United States is now
lower than suicide or car accidents. Penicillin has proven itself to be an incredibly strong
antibiotic that is harmful to bacteria but harmless to almost all other animal cells.
B. Lerner and K. Lerner (276-277) state that the discovery of many new strains of
bacteria that are resistant to penicillin has stimulated intense research on the search for new and
improved antibiotics. The field of antibiotics has expanded greatly to include thousands of new
antibiotics to cure the diseases caused by an undefined number of species of bacteria. According
to Hoyle (51-53), only a few years after the introduction of penicillin, a new bacterium called
Staphylococcus aureus was reported being resistant to penicillin, which caused horrible
infections. This discovery led to the introduction of new antibiotic research in learning about and
designing new drugs that kill the bacteria without stimulating the development of resistance.
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Research in the field of penicillin’s resistance to different species of bacteria has shown that high
doses of penicillin can kill some resistant bacteria that are not killed in a normal dose (Demerec
74). As new bacteria became resistant to penicillin, scientists found new ways to destroy the
bacteria including higher doses of penicillin and research into discovering new antibiotics.
Antibiotics play a major role in saving the lives of millions of people, and changing the
way people look at medicine. Alexander Fleming discovered penicillin by complete accident, but
this small mistake led to the advancement of many new antibiotics. Penicillin kills bacteria by
stopping their cells walls from working, so it helps stop hundreds of bacterial diseases in humans
from worsening. Penicillin has triggered the research and investigation into how to come up with
new antibiotics to stop new, resilient bacteria. Without antibiotics, medicine would not have
advanced nearly as fast as it did, and many more people would still suffer today from deadly
bacterial infections.
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Works Cited
Calvo, Sherri Chasin. "Sir Alexander Fleming." Science and Its Times. Ed. Neil Schlager and
Josh Lauer. Vol. 6: 1900 to 1949. Detroit: Gale, 2000. 373-374. Gale Virtual Reference
Library. Web. 24 Oct. 2011.
Demerec, M. "Origin of Bacterial Resistance to Antibiotics." Journal of Bacteriology 56 (1948):
63-74. Print.
Hoyle, Brian. "Antibiotic Resistance." Infectious Diseases: In Context. Ed. Brenda Wilmoth
Lerner and K. Lee Lerner. Vol. 1. Detroit: Gale, 2008. 51-55. Gale Virtual Reference
Library. Web. 2 Nov. 2011.
Woolf, S. J. "Sir Alexander Fleming--Man of Science and of Penicillin." American Scientist 33.4
(1945): 242-45. Print.
World of Microbiology and Immunology. Ed. Brenda Wilmoth Lerner and K. Lee Lerner. Vol. 1.
Detroit: Gale, 2003. 218-277. Gale Virtual Reference Library. Web. 24 Oct. 2011.