Penicillin was discovered by Alexander Fleming in 1928 and developed for use as a drug
by Howard Florey and Ernst Chain in England in the early 1940s. But the work on penicillin was
far from done. Scientists knew it was a powerful drug, but it could only be made in small
batches. In both the United States and the United Kingdom, the quest was on to figure out how to
mass produce penicillin. This involved the combined efforts of several laboratories and
pharmaceutical companies in the United States. Eventually they found the right “recipe” for
producing large vats of the penicillin extract during the critical years of World War II.
This kicked off a search to find other drugs that living things might be producing. So
further work on the search for antibiotics was done in the United States by René Dubos at the
Rockefeller Institute and Selman Waksman at Rutgers University.
Waksman maintained a life-long research interest in soil organisms including bacteria,
actinomycetes (filamentous bacteria), and fungi. He also actively
pursued studies of marine microbes. In 1939, Waksman began an extensive screening of thousands
of soil microbes, enlisting the help of some fifty graduate students and other scientists who
visited his Rutgers University laboratory.
This work took place over several decades. Some of the same techniques that Waksman developed
are used in the investigation activities Medicine from Dirt:
Isolation of Actinomycetes and Name that Actinomycete:
Isolating Soil Organisms.
From the
many antimicrobial agents isolated from soil actinomycetes, only streptomycin (purified by
Waksman's student, Albert Shatz, in 1943) proved to be safe for humans. Streptomycin
later proved to be a useful in treating tuberculosis. Another antibiotic, actinomycin, was
discovered later came and to be used as an anticancer agent.
Elizabeth Lee Hazen
(left) and Rachel Fuller Brown (right).
Two other people important to the research for effective antibiotics were
Elizabeth Lee Hazen and Rachel Fuller Brown. Hazen was a microbiologist orignally from
Mississippi and Brown was a chemist born and raised in Massachusetts. They both worked in
research laboratories of the New York State Department of Health and were interested in
Waksman's search for antimicrobial organisms in soil. By 1948, Hazen had identified new
antifungal agents among the actinomycetes using Waksman's soil-sample techniques. Brown's
task was to isolate the active ingredients from
cultures that Hazen had isolated, using solvent extractions. The
isolated active ingredient was then returned to Hazen to test against the fungi that seemed to
be susceptible to the extract. Nearly all the antifungal agents
that were effective in killing test fungi were also highly toxic in animals, unfortunately. But
one useful antifungal was found in the actinomycete Streptomyces nouresi. The species
name, nouresi, was the
Latin form of Nourse, the family name of friends of the two investigators. The Nourse family
supplied some soil from their garden, and it was from this dirt that the
Streptomyces nouresi organism was eventually extracted. The antifungal
agent was named nystatin, for the New York State Public Health Department for
which Hazen and Brown worked.
