Plant Lipid Metabolism

Abstract

This chapter focuses on the metabolism of plant lipids. Most lipids in plants are acyl lipids; that is, the main membrane lipids are glycosylglycerides or phosphoglycerides whereas the principal storage material is triacylglycerol. All of these molecules have fatty acids esterified to the glycerol backbone. Although, over 300 different fatty acids have been isolated in plants, only a few are commonly used by these organisms in their storage or membrane lipids. Most plants contain significant, though minor, amounts of myristic acid, and some important crops contain large quantities of medium-chain fatty acids such as capric or lauric. The latter acids are important in the detergent and cosmetic industries as well as providing easily absorbed lipid for patients with digestive disorders. Almost all plant membrane lipids are based on the trihydric alcohol glycerol. In the chloroplast membranes of photosynthetic tissues, the glycosylglycerides are the major components.This chapter discusses the chemistry of plant lipids and explains fatty acid biosynthesis, triacylglycerol synthesis, and membrane lipid biosynthesis. The chapter concludes with a discussion on lipid catabolism—cutin, suberins, and waxes—and plant membranes.