Macromolecular lipid assemblies

Macromolecular lipid assemblies arise from the amphiphilic character of phospholipids (Figure 1.89). Broadly speaking, all phospholipids contain a compact polar region, which is... 

Figure 1.89 Structure of dipalmitoyl L-a-phosphatidylcholine (DPPC) to illustrate the main molecular parameters and structural features that dictate the formation of crystalline lamellar phases of macromolecular lipid assemblies. Schematic representation of a phospholipid molecule is also show (inset).

The subject of hydrophobic interactions is controversial but nevertheless appears to be a very important for biological macromolecular cohesion in aqueous media, including most especially the cohesion of macromolecular lipid assemblies. The structure of water is critical to the existence of hydrophobic interactions (Figure 1.100). Water molecules consist of... 

There is by and large no need for the chemical synthesis of many of the phospholipids that make up macromolecular lipid assemblies in cells, since these are readily available from natural sources and are purified from these by HPLC. In effect, biological syntheses of lipids dominate chemical syntheses. However, there is some value in illustrating the general method... 

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