| Center
for Integrated Biotechnology
Definition
and Scope
What is Biotechnology?
Biotechnology
in one form or another has flourished since prehistoric times.
When the first human beings realized that they could
plant their own crops
and breed their own animals, they learned to use biotechnology. Discoveries
that fruit juices fermented into wine, that milk could be converted into
cheese or yogurt, or that beer could be made by fermenting solutions of
malt and hops began the study of biotechnology. When the first
bakers found that
they could make a soft, spongy bread rather than a firm, thin cracker,
they were acting as fledgling biotechnologists. The first animal
breeders, realizing
that different physical traits could be either magnified or lost by mating
appropriate pairs of animals, engaged in the manipulations of biotechnology.
What then is biotechnology? The term brings to mind many different things.
Some think of developing new types of animals. Others dream of almost unlimited
sources of human therapeutic drugs. Still others envision the possibility of
growing crops that are more nutritious and naturally pest-resistant to feed
a rapidly growing world population. This question elicits almost as many first-thought
responses as there are people to whom the question can be posed.
In its purest form, the term "biotechnology" refers
to the use of living organisms or their products to modify
human health and the human environment.
Prehistoric biotechnologists did this as they used yeast cells to raise bread
dough and to ferment alcoholic beverages, and bacterial cells to make cheeses
and yogurts, and as they bred their strong, productive animals to make even
stronger and more productive offspring.
Throughout human history, we have learned a great deal about the different
organisms that our ancestors used so effectively. The marked increase in our
understanding of these organisms and their cell products gains us the ability
to control the many functions of various cells and organisms. Using the techniques
of gene splicing and recombinant DNA technology, we can now actually combine
the genetic elements of two or more living cells. Functioning lengths of DNA
can be taken from one organism and placed into the cells of another organism.
As a result, for example, we can cause bacterial cells to produce human molecules.
Cows can produce more milk for the same amount of feed. And we can synthesize
therapeutic molecules that have never before existed.
Ref: Pamela Peters,
from Biotechnology: A Guide to Genetic Engineering. Wm.
C. Brown Publishers,
Inc., 1993.
Where
Did Biotechnology Begin?
With the Basics
Certain practices that we would now classify as applications of biotechnology
have been in use since man's earliest days. Nearly 10,000 years ago, our ancestors
were producing wine, beer, and bread by using fermentation, a natural process
in which the biological activity of one-celled organisms plays a critical role. In fermentation, microorganisms such as bacteria, yeasts, and molds are mixed
with ingredients that provide them with food. As they digest this food, the
organisms produce two critical by-products, carbon dioxide gas and alcohol.
In beer making, yeast cells break down starch and sugar (present in cereal
grains) to form alcohol; the froth, or head, of the beer results from the carbon
dioxide gas that the cells produce. In simple terms, the living cells rearrange
chemical elements to form new products that they need to live and reproduce.
By happy coincidence, in the process of doing so they help make a popular beverage.
Bread baking is also dependent on the action of yeast cells. The bread dough
contains nutrients that these cells digest for their own sustenance. The digestion
process generates alcohol (which contributes to that wonderful aroma of baking
bread) and carbon dioxide gas (which makes the dough rise and forms the honeycomb
texture of the baked loaf).
Discovery of the fermentation process allowed early peoples to produce foods
by allowing live organisms to act on other ingredients. But our ancestors also
found that, by manipulating the conditions under which the fermentation took
place, they could improve both the quality and the yield of the ingredients
themselves.
Crop Improvement
Although plant science is a relatively modern discipline, its fundamental
techniques have been applied throughout human history. When early man went
through the crucial transition from nomadic hunter to settled farmer, cultivated
crops became vital for survival. These primitive farmers, although ignorant
of the natural principles at work, found that they could increase the yield
and improve the taste of crops by selecting seeds from particularly desirable
plants.
Farmers long ago noted that they could improve each succeeding year's harvest
by using seed from only the best plants of the current crop. Plants that, for
example, gave the highest yield, stayed the healthiest during periods of drought
or disease, or were easiest to harvest tended to produce future generations
with these same characteristics. Through several years of careful seed selection,
farmers could maintain and strengthen such desirable traits.
The possibilities for improving plants expanded as a result of Gregor Mendel's
investigations in the mid-1860s of hereditary traits in peas. Once the genetic
basis of heredity was understood, the benefits of cross-breeding, or hybridization,
became apparent: plants with different desirable traits could be used to cultivate
a later generation that combined these characteristics.
An understanding of the scientific principles behind fermentation and crop
improvement practices has come only in the last hundred years. But the early,
crude techniques, even without the benefit of sophisticated laboratories and
automated equipment, were a true practice of biotechnology guiding natural
processes to improve man's physical and economic well-being.
Harnessing Microbes for Health
Every student of chemistry knows the shape of a Buchner funnel, but they may
be unaware that the distinguished German scientist it was named after made
the vital discovery (in 1897) that enzymes extracted from yeast are effective
in converting sugar into alcohol. Major outbreaks of disease in overcrowded
industrial cities led eventually to the introduction, in the early years of
the present century, of large-scale sewage purification systems based on microbial
activity. By this time it had proved possible to generate certain key industrial
chemicals (glycerol, acetone, and butanol) using bacteria. Another major beneficial legacy of early 20th century biotechnology was the
discovery by Alexander Fleming (in 1928) of penicillin, an antibiotic derived
from the mold Penicillium. Large-scale production of penicillin was achieved
in the 1940s. However, the revolution in understanding the chemical basis of
cell function that stemmed from the post-war emergence of molecular biology
was still to come. It was this exciting phase of bioscience that led to the
recent explosive development of biotechnology.
Ref: "Biotechnology
at Work" and "Biotechnology in Perspective," Washington,
D.C.: Biotechnology Industry Organization, 1989, 1990.
Overview
and Brief History
Biotechnology
seems to be leading a sudden new biological revolution. It has brought us
to the brink of a world
of "engineered" products that
are based in the natural world rather than on chemical and industrial processes.
Biotechnology
has been described as "Janus-faced." This implies
that there are two sides. On one side, techniques allow DNA to be manipulated
to move genes from one organism to another. On the other, it involves relatively
new technologies whose consequences are untested and should be met with caution.
The term "biotechnology" was coined in 1919 by Karl Ereky, an Hungarian
engineer. At that time, the term meant all the lines of work by which products
are produced from raw materials with the aid of living organisms. Ereky envisioned
a biochemical age similar to the stone and iron ages.
A common misconception among teachers
is the thought that biotechnology includes only DNA and genetic engineering.
To keep students abreast of current knowledge,
teachers sometimes have emphasized the techniques of DNA science as the "end-and-all" of
biotechnology. This trend has also led to a misunderstanding in the general
population. Biotechnology is NOT new. Man has been manipulating living things
to solve problems and improve his way of life for millennia. Early agriculture
concentrated on producing food. Plants and animals were selectively bred, and
microorganisms were used to make food items such as beverages, cheese, and
bread.
The late eighteenth century and the beginning of the nineteenth century saw
the advent of vaccinations, crop rotation involving leguminous crops, and animal
drawn machinery. The end of the nineteenth century was a milestone of biology.
Microorganisms were discovered, Mendel's work on genetics was accomplished,
and institutes for investigating fermentation and other microbial processes
were established by Koch, Pasteur, and Lister.
Biotechnology at the beginning of
the twentieth century began to bring industry and agriculture together. During
World War I, fermentation processes were developed
that produced acetone from starch and paint solvents for the rapidly growing
automobile industry. Work in the 1930s was geared toward using surplus agricultural
products to supply industry instead of imports or petrochemicals. The advent
of World War II brought the manufacture of penicillin. The biotechnical focus
moved to pharmaceuticals. The "cold war" years were dominated by
work with microorganisms in preparation for biological warfare, as well as
antibiotics and fermentation processes.
Biotechnology is currently being used in many areas including agriculture,
bioremediation, food processing, and energy production. DNA fingerprinting
is becoming a common practice in forensics. Similar techniques were used recently
to identify the bones of the last Czar of Russia and several members of his
family. Production of insulin and other medicines is accomplished through cloning
of vectors that now carry the chosen gene. Immunoassays are used not only in
medicine for drug level and pregnancy testing, but also by farmers to aid in
detection of unsafe levels of pesticides, herbicides, and toxins on crops and
in animal products. These assays also provide rapid field tests for industrial
chemicals in ground water, sediment, and soil. In agriculture, genetic engineering
is being used to produce plants that are resistant to insects, weeds, and plant
diseases.
A current agricultural controversy
involves the tomato. A recent article in the New Yorker magazine compared
the discovery of the edible tomato that came
about by early biotechnology with the new "Flavr-Savr" tomato brought
about through modern techniques. In the very near future, you will be given
the opportunity to bite into the Flavr-Savr tomato, the first food created
by the use of recombinant DNA technology ever to go on sale.
What will you think as you raise
the tomato to your mouth? Will you hesitate? This moment may be for you as
it was for Robert Gibbon Johnson in 1820 on the
steps of the courthouse in Salem, New Jersey. Prior to this moment, the tomato
was widely believed to be poisonous. As a large crowd watched, Johnson consumed
two tomatoes and changed forever the human-tomato relationship. Since that
time, man has sought to produce the supermarket tomato with that "backyard
flavor." Americans also want that tomato available year-round.
New biotechnological
techniques have permitted scientists to manipulate desired traits. Prior
to the advancement
of the methods of recombinant DNA, scientists
were limited to the techniques of their time -- cross-pollination, selective
breeding, pesticides, and herbicides. Today's biotechnology has its "roots" in
chemistry, physics, and biology . The explosion in techniques has resulted
in three major branches of biotechnology: genetic engineering, diagnostic techniques,
and cell/tissue techniques.
Ref: Ann
Murphy and Judy Perrella. Woodrow Wilson Foundation Biology Institute. "A Further Look at Biotechnology." Princeton,
NJ: The Woodrow Wilson National Fellowship Foundation, 1993. |