Design of New Plant Products: Engineering of Fatty Acid Metabolism

PLANTS AS CHEMICAL FACTORIES Manipulation of biosynthetic pathways in transgenic plants offers a number of exciting opportunities for plant biochemists and molecular biologists to redesign plant metabolism toward production of specific higher-value products. Here I review several recent examples that have demonstrated that plant fatty acid metabolism can be manipulated in useful ways to produce new and potentially more valuable vegetable oils. A number of factors have converged to make metabolic engineering of fatty acid metabolism particularly attractive. Although for centuries plant breeders have manipulated plant metabolism, the primary goal has been to produce better yields of crops for human and animal consumption, and in the past 100 years, efforts to increase yields of the basic food crops have had dramatic success. Through a number of technological advances, yields per hectare have risen manyfold, resulting in substantial surplus capacity worldwide. These surpluses are a reflection of the high yields that can be obtained when optimum agronomic practices are applied to highly developed crop varieties. As a result, the United States spends 20 to 30 billion annually on a variety of programs designed to deal with farm overproduction capacity.