ABSTRACT
This chapter discusses the biological distribution of phospholipids in bacteria, fungi, plants, invertebrates, fish, and mammals. It reviews the variability and asymmetry of the phospholipid composition in mammalian membranes. The advancements made in the technology for examining phospholipid composition have increased our ability to detect specific changes in cellular membrane structure. Improvements in thin-layer chromatography and high-performance liquid chromatography have increased our ability to separate major phospholipid classes as well as separate phospholipid molecular species. Phospholipids in plant cells are primarily constituents of lipoprotein membrane structures. Phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol are the major phospholipids in high plants. Plants also contain lesser amounts of phosphatidylinositol and diphosphatidylglycerol. The fatty acid composition of plant lipids is dependent upon environmental conditions, particularly light and temperature. Many different fatty acids have been detected in plants, but a few common fatty acids account for the majority of the fatty acids in phospholipids.
