WORLD OF MICROBIOLOGY AND IMMUNOLOGY Edelman, Gerald M.175•
Microorganisms are used to enhance the nutritional content of
plants and other food sources. The growing nutraceutical sec-
tor relies in part on the nutritional enhancements afforded by
microbes. Bacteria are also useful in providing a degree of
resistance to plants. An example is the use of Bacillus thurin-
gensisto supply a protein that is lethal to insect when they
consume it. The use of bacterial insecticides has reduced the
use of chemical insecticides, which is both a cost savings to
the producer and less stressful on the environment. Other bac-
terial enzymes and constituents of the organisms are utilized to
produce materials such as plastic.
A process known as DNA fingerprinting, which relies
upon enzymes that are produced and operate in bacteria, has
enabled the tracing of the fate of genes in plant and animal pop-
ulations, and enhanced gathering of evidence at crime scenes.
The mode of growth of bacterial populations has also
proved to be exploitable as a production tool. A prime exam-
ple is the surface-adherent mode of bacterial growththat is
termed a biofilm. Although not known at the time, the produc-
tion of vinegar hundreds of years ago was, as now, based on
the percolation of water through biofilms growing on wood
shavings. Immobilized bacteria can produce all manner of
compounds. As well, the cells can provide a physical barrier to
the flow of fluid. This dynamic aspect has been utilized in a so
far small-scale way to increase the production of oil from
fields oil thought to be depleted. Bacteria can plug up the
zones were water and oil flows most easily. Subsequent pump-
ing of water through the field forces the oil still resident in
lower permeability areas to the surface.
With the passing of time, the realized and potential ben-
efits of microorganisms and the implementation of strict stan-
dards of microbe use, is lessening the concern over the use of
engineered microorganisms for economic and social benefit.
The use of microorganisms can only increase.See also Bioremediation; Composting, microbiological
aspects; DNA chips and micro arraysEEdelman, Gerald M.DELMAN, GERALDM.(1929- )
American biochemistFor his “discoveries concerning the chemical structure of anti-
bodies,” Gerald M. Edelman and his associate Rodney Porter
received the 1972 Nobel Prize in physiology or medicine.
During a lecture Edelman gave upon acceptance of the prize,
he stated that immunology“provokes unusual ideas, some of
which are not easily come upon through other fields of
study.... For this reason, immunology will have a great impact
on other branches of biology and medicine.” He was to prove
his own prediction correct by using his discoveries to draw
conclusions not only about the immune systembut about the
nature of consciousness as well.
Born in New York City to Edward Edelman, a physi-
cian, and Anna Freedman Edelman, Gerald Maurice Edelman
attended New York City public schools through high school.
After graduating, he entered Ursinus College, in Collegeville,
Pennsylvania, where he received his B.S. in chemistry in- Four years later, he earned an M.D. degree from the
University of Pennsylvania’s Medical School, spending a year
as medical house officer at Massachusetts General Hospital.
In 1955, Edelman joined the United States Army
Medical Corps, practicing general medicine while stationed at
a hospital in Paris. There, Edelman benefited from the heady
atmosphere surrounding the Sorbonne, where future Nobel
laureates Jacques Lucien Monodand François Jacobwere
originating a new study, molecular biology. Following his
1957 discharge from the Army, Edelman returned to New York
City to take a position at Rockefeller University studying
under Henry Kunkel. Kunkel, with whom Edelman would
conduct his Ph.D. research, and who was examining the
unique flexibility of antibodies at the time.
Antibodies are produced in response to infection in
order to work against diseases in diverse ways. They form a
class of large blood proteins called globulins—more specifi-
cally, immunoglobulins—made in the body’s lymph tissues.
Each immunoglobulin is specifically directed to recognize and
incapacitate one antigen, the chemical signal of an infection.
Yet they all share a very similar structure.
Through the 1960s and 1970s, a debate raged between
two schools of scientists to explain the situation whereby anti-
bodies share so many characteristics yet are able to perform
many different functions. In one camp, George Wells Beadle
and Edward Lawrie Tatumargued that despite the remarkable
diversity displayed by each antibody, each immunoglobulin,
must be coded for by a single gene. This has been referred to
as the “one gene, one protein” theory. But, argued the oppos-
ing camp, led by the Australian physician Sir Frank Macfarlane
Burnet, if each antibody required its own code within the DNA
(deoxyribonucleic acid), the body’s master plan of protein
structure, the immune system alone would take up all the pos-
sible codes offered by the human DNA.
Both camps generated theories, but Edelman eventually
disagreed with both sides of the debate, offering a third possi-
bility for antibody synthesis in 1967. Though not recognized
at the time because of its radical nature, the theory he and his
associate, Joseph Gally, proposed would later be confirmed as
essentially correct. It depended on the vast diversity that can
come from chance in a system as complex as the living organ-
ism. Each time a cell divided, they theorized, tiny errors in the
transcription—or reading of the code—could occur, yielding
slightly different proteins upon each misreading. Edelman and
Gally proposed that the human body turns the advantage of
this variability in immunoglobulinsto its own ends. Many
strains of antigens when introduced into the body modify the
shape of the various immunoglobulins in order to prevent the
recurrence of disease. This is why many illnesses provide for
their own cure—why humans can only get chicken pox once,
for instance.
But the proof of their theory would require advances in
the state of biochemical techniques. Research in the 1950s and
1960s was hampered by the difficulty in isolating
immunoglobulins. The molecules themselves are compara-
tively large, too large to be investigated by the chemical means
then available. Edelman and Rodney Porter, with whom
Edelman was to be honored with the Nobel Prize, sought
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