Abstract
Phospholipids are amphiphilic molecules and essential to form cell membranes in all organisms including animals, plants, fungi, and bacteria. Phospholipid molecules are composed of a hydrophilic head group and two hydrophobic acyl chains, and divided into classes based on their molecular structures. In mammalian cells, major phospholipid classes are phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidic acid (PA), phosphatidylinositol (PI), phosphatidylglycerol (PG), cardiolipin (CL), and sphingomyelin (SM). In addition to the structural roles in membrane formation, phospholipids play important roles in various cellular functions, including membrane trafficking, intracellular signaling, and cell growth. To further understand the cellular and molecular mechanisms, we have completed the development of enzymatic fluorometric methods for quantifying all major phospholipid classes, namely PC, PE, PS, PA, PI, PG ＋ CL, and SM, which are specific, sensitive and high–throughput. These methods enable us to assess the phospholipid class compositions in cultured cells and their intracellular organelles. In this review, I describe strategies and procedures for the enzymatic fluorometric assays of phospholipid classes.
