2.7 Membrane Lipids: Phospholipids

• Phospholipid

  • Lipid that contains one or more fatty acids, a phosphate group, a platform molecule to which the fatty acid(s) and the phosphate group are attached, and an alcohol that is attached to the phosphate group
• All cells are surrounded by a membrane that confines their contents.
• Up to 80% of the mass of a cell membrane can be lipid materials dominated by phospholipids.
• Types of Phospholipids Based on Platform Molecule:

  • Glycerophospholipid
  • Sphingophospholipid
• Glycerophospholipid

  • Lipids that contain two fatty acids and a phosphate group esterified to a glycerol molecule and an alcohol esterified to the phosphate group .
  • All attachments (bonds) between groups are ester linkages.
• Sphingophospholipid

  • Structures based on the 18-carbon monounsaturated aminodialcohol sphingosine
  • Contains one fatty acid and one phosphate group attached to a sphingosine molecule, and an alcohol attached to the phosphate group.