BIOL 102 Lecture Notes - Lecture 15: Lipidomics, Sphingolipid, Sphingomyelin
Document Summary
Lipidomics: the field defining the number and biological function of lipids, is revealing a significant diversity in membrane lipids. Over 1000 distinct identified in cells, organize them into three classes. Glycerol phospholipids, sphingolipids, and sterols such as cholesterol. The classical phospholipid bilayer consists of a combination of glycerol phospholipids and sphingolipids. Head groups can have both positive and negative charge = zwitterionic. Phospholipids: can vary in length and composition of the fatty acid tail saturated or cis-unsaturated. Different cellular compartments have distinct membrane lipid composition phospholipids spontaneously form bilayers. Spontaneously form bilayers because of their amphipathic structure. Two nonpolar fatty acids extend in one direction, roughly parallel to each other. Polar phosphate group points in the other direction. Polar water molecules repel the long, nonpolar tails of the phospholipid while seeking partners for hydrogen bonding phospholipids end up packed closely together, sequestered as far as possible from water.
