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Alexander Fleming
1881 - 1955

A spore that drifted into his lab and took root on a culture
dish started a chain of events that altered forever the
treatment of bacterial infections
By DR. DAVID HO for Time Magazine
The
improbable chain of events that led Alexander Fleming to
discover penicillin in 1928 is the stuff of which scientific
myths are made. Fleming, a young Scottish research scientist
with a profitable side practice treating the syphilis infections
of prominent London artists, was pursuing his pet theory — that
his own nasal mucus had antibacterial effects — when he left a
culture plate smeared with Staphylococcus bacteria on his lab
bench while he went on a two-week holiday.
When he returned, he noticed a clear halo surrounding the
yellow-green growth of a mold that had accidentally contaminated
the plate. Unknown to him, a spore of a rare variant called
Penicillium notatum had drifted in from a mycology lab one floor
below. Luck would have it that Fleming had decided not to store
his culture in a warm incubator, and that London was then hit by
a cold spell, giving the mold a chance to grow. Later, as the
temperature rose, the Staphylococcus bacteria grew like a lawn,
covering the entire plate — except for the area surrounding the
moldy contaminant. Seeing that halo was Fleming's "Eureka"
moment, an instant of great personal insight and deductive
reasoning. He correctly deduced that the mold must have released
a substance that inhibited the growth of the bacteria.
It was a discovery that would change the course of history. The
active ingredient in that mold, which Fleming named penicillin,
turned out to be an infection-fighting agent of enormous
potency. When it was finally recognized for what it was — the
most efficacious life-saving drug in the world — penicillin
would alter forever the treatment of bacterial infections. By
the middle of the century, Fleming's discovery had spawned a
huge pharmaceutical industry, churning out synthetic penicillins
that would conquer some of mankind's most ancient scourges,
including syphilis, gangrene and tuberculosis.
Fleming was born to a Scottish sheep-farming family in 1881. He
excelled in school and entered St. Mary's Hospital in London to
study medicine. He was a short man, usually clad in a bow tie,
who even in his celebrity never mastered the conventions of
polite society. Fleming probably would have remained a quiet
bacteriologist had serendipity not come calling that fateful
September in 1928.
In fact, Fleming was not even the first to describe the
antibacterial properties of Penicillium. John Tyndall had done
so in 1875 and, likewise, D.A. Gratia in 1925. However, unlike
his predecessors, Fleming recognized the importance of his
findings. He would later say, "My only merit is that I did not
neglect the observation and that I pursued the subject as a
bacteriologist." Although he went on to perform additional
experiments, he never conducted the one that would have been
key: injecting penicillin into infected mice. Fleming's initial
work was reported in 1929 in the British Journal of Experimental
Pathology, but it would remain in relative obscurity for a
decade.
By 1932, Fleming had abandoned his work on penicillin. He would
have no further role in the subsequent development of this or
any other antibiotic, aside from happily providing other
researchers with samples of his mold. It is said that he lacked
both the chemical expertise to purify penicillin and the
conviction that drugs could cure serious infections. However, he
did safeguard his unusual strain of Penicillium notatum for
posterity. The baton of antibiotic development was passed to
others.
In 1939 a specimen of Fleming's mold made its way into the hands
of a team of scientists at Oxford University led by Howard
Florey, an Australian-born physiologist. This team had technical
talent, especially in a chemist named Ernst Boris Chain, who had
fled Nazi Germany. Armed with funding from the Rockefeller
Foundation, these scientists made it their objective to identify
and isolate substances from molds that could kill bacteria. The
mission was inspired by the earlier work of Gerhard Domagk, who
in 1935 showed that the injection of a simple compound,
Prontosil, cured systemic streptococcal infections. This
breakthrough demonstrated that invading bacteria could be killed
with a drug and led to a fevered search in the late 1930s for
similar compounds. Fleming's Penicillium notatum became the
convenient starting point for Florey's team at Oxford.
In a scientific tour de force, Florey, Chain and their
colleagues rapidly purified penicillin in sufficient quantity to
perform the experiment that Fleming could not: successfully
treating mice that had been given lethal doses of bacteria.
Within a year, their results were published in a seminal paper
in the Lancet. As the world took notice, they swiftly
demonstrated that injections of penicillin caused miraculous
recoveries in patients with a variety of infections.
The Oxford team did not stop there. Rushing to meet the needs of
World War II, they helped the government set up a network of "minifactories"
for penicillin production. Florey also played a crucial role in
galvanizing the large-scale production of penicillin by U.S.
pharmaceutical companies in the early 1940s. By D-day there was
enough penicillin on hand to treat every soldier who needed it.
By the end of World War II, it had saved millions of lives.
Pneumonia, syphilis, gonorrhea, diphtheria, scarlet fever and
many wound and childbirth infections that once killed
indiscriminately suddenly became treatable. As deaths caused by
bacterial infections plummeted, a grateful world needed a hero.
Fleming alone became such an object of public adulation,
probably for two reasons. First, Florey shunned the press, while
Fleming seemed to revel in the publicity. Second, and perhaps
more important, it was easier for the admiring public to
comprehend the deductive insight of a single individual than the
technical feats of a team of scientists.
Awards and accolades came to Fleming in rapid succession,
including a knighthood (with Florey) in 1944 and the Nobel Prize
for Medicine (with Florey and Chain) in 1945. By this time, even
Fleming was aware that penicillin had an Achilles' heel. He
wrote in 1946 that "the administration of too small doses ...
leads to the production of resistant strains of bacteria." It's
a problem that plagues us to this day.
When he died of a heart attack in 1955, he was mourned by the
world and buried as a national hero in the crypt of St. Paul's
Cathedral in London. Although Fleming's scientific work in and
of itself may not have reached greatness, his singular
contribution changed the practice of medicine. He deserves our
utmost recognition. At the same time, we must bear in mind that
the "Fleming Myth," as he called it, embodies the
accomplishments of many giants of antibiotic development.
Fleming is but a chosen representative for the likes of Florey,
Chain, Domagk, Selman Waksman and Rene Dubos, many of whom
remain, sadly, virtual unknowns. Their achievements have made
the world a better, healthier place. In commemorating Fleming,
we commemorate them all.
~~~<"((((((><~~~<"((((((><~~~<"((((((><~~~<"((((((><~~~<"((((((><~~~
The Scottish bacteriologist Sir Alexander Fleming (1881-1955) is
best known for his discovery of penicillin, which has been
hailed as "the greatest contribution medical science ever made
to humanity."
Alexander Fleming was born on Aug. 6, 1881, at Lochfield,
Ayrshire, one of the eight children of Hugh Fleming, a farmer.
Nature, which he considered his first and best teacher,
developed his power of observation and taught him to apply his
powers of reasoning to what he observed and to act in accordance
with his observations. Like many Scots who were forced to leave
their native land for better career opportunities, Fleming, at
the age of 13, left for London, where he lived with his
brothers. He attended lectures at the Polytechnic School and
worked for 4 years in a shipping office. In 1901 an uncle left
Fleming a legacy that enabled him to study medicine, and he
entered St. Mary's Hospital Medical School in Paddington, later
a part of the University of London.
In 1906 Fleming received his licentiate from the Royal College
of Physicians. He chose a career in bacteriology and immediately
joined the Inoculation Department, now the Wright-Fleming
Institute, where he spent his entire career. He assisted Sir
Almroth Wright, the originator of vaccinotherapy (therapeutic
inoculation for bacterial infection) and the first doctor to use
antityphoid vaccines on human beings. Fleming's research at this
time primarily involved the use of Paul Ehrlich's Salvarsan in
the treatment of syphilis. In 1908 Fleming passed his final
medical examinations, winning the Gold Medal of the University
of London. He was awarded the Cheadle Medal for his thesis
"Acute Bacterial Infections," which foreshadowed the line of
work he followed throughout his life.
During World War I Fleming served in the Royal Army Medical
Corps, specializing in the treatment of wounds by antiseptics.
He noticed that phagocytosis (the ingestion and destruction of
infectious microbes by the cells) was more active in war wound
infections than in ordinary wound infections, and he advised
surgeons to remove all necrotic tissue as soon as possible. He
observed that antiseptics not only did nothing to prevent
gangrene but actually promoted its development by destroying
leukocytes. Although Fleming's later discoveries have
overshadowed this work, some authorities believe that he never
conceived anything more perfect or ingenious than these
brilliant experiments by which he demonstrated the danger to
human tissues of incorrectly administered antiseptics.
In 1915, while on leave, Fleming married Sarah Marion McElroy,
an Irish nurse who operated a private nursing home in London.
The couple had one son, Robert.
Lysozyme Research
In 1921, the year he became assistant director of the
Inoculation Department at St. Mary's, Fleming discovered that
nasal mucus, human tears, and, especially, egg whites contain a
chemical substance with marked bactericidal properties. Inasmuch
as it lysed (dissolved) microbes and had the properties of an
enzyme, Fleming called it lysozyme. Élie Metchnikoff believed
that bodily secretions removed microbes by mechanical rather
than chemical means, an opinion held in 1921 by most
bacteriologists. Fleming now challenged this view, but his work
met a cold reception. Between 1922 and 1927 he published five
more articles on lysozyme: he proved that antiseptics then in
use, even in much weaker solutions than necessary to fight
septicemia, would destroy leukocytes, and that "whereas egg
white … has no destructive effects on the leukocytes, it has
considerable inhibitory or lethal effect on some of the
bacteria."
Discovery of Penicillin
The leitmotiv of Fleming's career was his search for a chemical
substance which would destroy infectious bacteria without
destroying tissues or weakening the body's defenses. In 1928 an
accidental observation, which was a direct result of his
apparently disorderly habit of not discarding culture plates
promptly, led to the fulfillment of his goal. Fleming noted that
on a culture plate of staphylococci a mold (Penicillium notatum)
which had been introduced by accidental contamination had
dissolved the colonies of staphylococci - an example of
antibiosis. He found that the broth containing the bactericidal
substance (penicillin) produced by the mold was unstable and
rapidly lost its activity. Furthermore, it could not be used for
injections until freed from foreign protein. Clearly, a method
of extraction and concentration of the crude substance was
required. Fleming had no chemist or biochemist on his staff, and
he encouraged others to attempt the task.
In 1935 Howard W. Florey, an Australian experimental
pathologist, and Ernst B. Chain, a Jewish chemist who had fled
from Nazi Germany, came to Oxford University, where in 1939 they
took up Fleming's work on penicillin. By employing the
relatively new technique of lyophilization, Florey and Chain
isolated the drug in completely purified form, which was a
million times more active than Fleming's crude substance of
1928, and in 1940 they published the results of their successful
treatment of infected white mice. A completely successful test
involving a human being was not accomplished until 1942 because
of the limited supply of the drug. By 1943 factories in England
and the United States were producing penicillin on a large
scale, and it became available for military use. By 1944 the
miracle drug became available for civilian use.
Fleming never collected royalties on penicillin. In 1945 he
received the Nobel Prize in physiology or medicine and toured
the United States, where he was hailed as a hero. American
chemical firms collected $100,000 and presented it to him in
gratitude for his contribution to medical science. He refused to
accept the money personally but used it for research at St.
Mary's.
In 1946 Fleming became director of the Institute, a position he
held until 1955. In 1951 he was elected rector of Edinburgh
University. His wife had died in 1949, and in 1953 he married
Amalia Coutsouris-Voureka, a Greek medical worker who had come
to London in 1946 to work with him. Fleming died on March 11,
1955, and was buried in the crypt of St. Paul's Cathedral in
London. According to André Maurois, "No man, except Einstein in
another field, and before him Pasteur, has had a more profound
influence on the contemporary history of the human race."
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This web page was last updated on:
10 December, 2008
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