Biotechnology

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Key Concepts

13.1 Recombinant DNA Can Be Made in the Laboratory

13.2 DNA Can Genetically Transform Cells and Organisms

13.3 Genes Come from Various Sources and Can Be Manipulated

13.4 Biotechnology Has Wide Applications

Ananda Chakrabarty received the first patent for a genetically modified organism, a bacterium that breaks down crude oil.

The United Nations defines biotechnology as “any technological application that uses biological systems, living organisms, or derivatives thereof to make or modify products or processes.” This definition encompasses major human activities such as brewing beer (see Chapter 6) and the domestication of animals and plants (see Chapter 12). More recently, biotechnology has become associated with the genetic modification of microorganisms for the production of particular substances, and of a variety of plants and animals used in agriculture.

Industrial biotechnology began in England in 1917, during the First World War. The production of cordite, an explosive used to propel a bullet or shell to its target, required the solvent acetone, (CH3)2CO. But most acetone was manufactured by England’s enemy, Germany. A microbiologist at the University of Manchester, Chaim Weizmann, found that if the bacterium Clostridium acetylbutylicum was grown using starch as an energy source, it produced abundant quantities of acetone. The British government set up a factory to grow large vats of these bacteria, and the cordite shortage was solved.

The contemporary era of biotechnology as a major industry dates from June 16, 1980, on the steps of the U.S. Supreme Court. In this case, scientists were studying bacteria not for their ability to make something, but to break it down. Many bacteria have genes that code for unusual enzymes and biochemical pathways, and they can use all sorts of substances as nutrients, including pollutants. Scientists have identified these organisms simply by mixing polluted soil with water and seeing what grows. In 1971, Ananda Chakrabarty at the General Electric Research Center in New York used genetic crosses to develop a single strain of the bacterium Pseudomonas that carried genes for the breakdown of various hydrocarbons in oil. He and his company applied for a patent to legally protect their discovery and profit from it. Nine years later, in a landmark case, the U.S. Supreme Court ruled that “a live, human-made microorganism is patentable” under the U.S. Constitution.

The 1980 Supreme Court ruling came at a time when new laboratory methods were being developed to insert specific DNA sequences into organisms by recombinant DNA technology. The resulting flood of patents for DNA sequences and genetically modified organisms, some of them developed to improve the environment, continues to this day and was the subject of another Supreme Court ruling in 2013.

Question 13.1

How is biotechnology used to alleviate environmental problems?

You will find the answer to this question on page 271.

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